Pain after surgery is a major issue for patient discomfort and often associated with delayed recovery. The aim of the present study was to evaluate the prevalence of pain and requirement for analgesics up to 6 months after elective surgery, independent if new pain symptoms occurred after surgery or if preoperative pain persisted in the postoperative period.A prospective observational single center cohort study was conducted between January 2012 and August 2013. Eligible patients were scheduled to undergo elective surgical interventions including joint , back , or urological surgery . Pain was assessed on an 11-point numerical rating scale (NRS) before, on postoperative day 2 and 6 months after surgery. Clinical information was collected with structured questionnaires and by telephone interview.p < .001). 35.3 % of the patients after joint surgery and 41.3 % after back surgery still use pain medication 6 months postoperatively, in contrast to 7.3 % of patients after urological surgery. 13.6 % of patients who underwent back surgery indicated the regular intake of opioids.Six hundred and forty-four patients gave informed consent, including 54.4 % men . Higher preoperative pain scores were found in patients undergoing joint  and back surgery  than in patients prior to urological surgery . After 6 months, about 50 % of patients after joint or back surgery indicated pain levels ≥3/10, compared to 15.9 % of patients after urological surgery ; date of registration December 6th 2011.Clinicaltrials.gov (Identifier: The online version of this article (doi:10.1186/s12871-016-0261-7) contains supplementary material, which is available to authorized users. Postsurgical pain is a major issue for patient discomfort associated with delayed recovery and prolonged hospital stay , 2 and rHowever, the persistence of pain after surgery may lead to functional impairment with consecutive disability and immobility and affect the patients’ quality of life.Adequate pain management helps to prevent or to diminish postoperative complications, such as respiratory or cardiovascular problems, or postoperative delirium –10. PrevThe aim of this prospective study was to explore the prevalence of pain and requirement for analgesics up to 6 months after elective surgery considering different procedures in joint, back and urological surgery.This single center clinical study was conducted at the Department of Anaesthesiology at the University Medical Center of the Johannes Gutenberg University Mainz, Germany. Data presented here are a subset of a larger data set evaluating outcome variables after major surgery . Ethical approval for this study [Ethical Committee N° 837.519.11 (8061)] was provided on 3rd January 2012 by the Regional Ethics Committee of Rhineland-Palatinate, Mainz, Germany. The study was registered in clinicaltrials.gov (Identifier: NCT01488617). Written informed consent was obtained from all patients. From January 2012 to August 2013 a total of 821 patients undergoing elective surgery were eligible, from whom 644 (78.4 %) agreed to participate  before surgery, on the second postoperative day, and 6 months after surgery. Pain duration like chronic preoperative pain was defined as pain ≥3/10 NRS for at least 6 months. Pain at 6 months after surgery was defined as at least 3/10 on a NRS, corresponding to moderate pain with a potential impact on physical or emotional functioning . ClinicaIntraoperative analgesia was obtained with a combination of general anaesthesia and if indicated epidural anaesthesia by a continuous epidural infusion of bupivacaine 0.125 % with fentanyl 2 μg/ml and postoperative supplemented with patient controlled epidural analgesia (PCEA).Standard postoperative pain treatment in the post anaesthesia care unit (PACU) for patients without epidural catheter consisted of patient controlled intravenous analgesia (PCIA) with piritramide . In addition, patients with PCIA received non-opioids . Patients undergoing back surgery received a standard analgesic regimen with non-opioids, supplemented with opioids (15 mg piritramide subcutaneously), if indicated.On the normal ward, pain treatment is provided and customized twice daily by an acute pain unit, consisting of anaesthesiologists and nursing staff.N = 145 participants in each surgery group to obtain 95 % confidence intervals of +/− 8 % was required. Descriptive statistics are expressed as absolute and relative frequencies (%) or mean (SD). Differences between groups were examined using parametric Student’s t-test or appropriate nonparametric tests . Spearman rank correlation (r) was used to examine the association between metric variables. Patients with (NRS ≥3) and without clinically relevant pain at 6 months were compared using cross tabulation and chi-square-tests.As in this study descriptive data, i.e. prevalences, were analyzed, a formal power calculation was not required. Assuming a prevalence of 40 % for pain 6 months after surgery, recruitment of P-value < .05 was considered statistically significant. No adjustment for multiple testing was performed, therefore only the local significance level α = 0.05 is kept.All analyses were performed using IBM SPSS Statistics for Windows, Version 22 . From January 2012 to August 2013 644 patients agreed to participate, from which 105 patients had to be withdrawn during the further course of the study for different reasons  included predominantly hip prosthesis (49.7 %), knee prosthesis (48.6 %), shoulder prosthesis (1.7 %). Back surgery (N = 201) included discectomy or hemilaminectomy (77.6 %), spondylodesis (20.9 %), and others (1.5 %). Urological surgery comprised (N = 165), patients with cystectomy , nephrectomy (27.3 %), radical prostatectomy (38.2 %), and others (3 %).Patients underwent different interventions in orthopedic, neurosurgical and urological surgery. Joint surgery , compared to 1.7 % in joint and 2.5 % in back surgery.Pain data are presented in Table p < .001) and 6 months after surgery , while there were no differences on the second postoperative day. Subdivided into surgery groups, the preoperative gender-specific differences were not confirmed in the joint surgery group (p = .345). Also in the catamnesis, no gender-specific differences were observed in patients undergoing joint (p = .987) and back surgery (p = .629) indicating similar pain levels in men and women in these subsamples, respectively.Considering the entire sample, women indicated higher mean pain scores than men both preoperatively .41.5 % of the patients in our sample experienced clinically relevant pain 6 months after surgery, with different rates in each surgery group Fig. . After jTable N = 63, mean = 0.6, SD = 0.2). Considering surgical interventions that were performed in both men and women (nephrectomies and cystectomies), the comparison of pain scores at 6 months revealed no significant differences . This also applies for the percentage of clinically relevant pain 6 months after surgery .Significant differences between men and women were observed in patients undergoing urological surgery. First, there were only 40 women (26.5 %) in this group of 151 patients. Furthermore, 63 male patients underwent radical prostatectomy (RPX), being associated with low postoperative pain scores .BMI levels were slightly higher in patients who indicated pain compared to patients without pain, however, differences in BMI levels did not reach statistical significance  differed significantly between patients 6 month after surgery. Patients who suffered from pain at 6 months were more likely to have reported preoperative pain intensity of ≥ 3/10 NRS or to suffer from preoperative pain for more than 6 months prior to surgery.Considering the duration of surgery, no significant differences between patients with or without pain were noticed between any of the surgery groups Table .The results of the present study demonstrate that a significant number of patients report persistent pain and intake of analgesic medication, even opioids, up to 6 months after surgery.Considering the different surgery groups, more than 50 % of patients after back and joint surgery indicated clinically relevant pain 6 months after surgery. Patients undergoing joint or lumbar spine surgery for degenerative conditions often have poor outcomes following the surgical intervention, with up to 40 % reporting residual chronic pain , 18. ManEspecially in patients with degenerative diseases of joint or vertebral column, the patients’ burden of pain often triggers the indication for surgery. Therefore, these patients do not meet the above-mentioned criteria for persistent post-surgical pain. In contrast, in patients undergoing major surgery due to urological tumors, preoperative pain is not a leading symptom.We decided to follow-up patients up to 6 months after surgery assuming that postoperative rehabilitation programs were completed at that time and prolonged inflammatory processes would have been subsided . PatientWith regard to postoperative pain, patients with renal cancer  or with In contrast to other studies, we evaluated prevalence and intensity of pain 6 months after surgery in combination with the need for pain medication. We assumed that after joint and back surgery, pain symptoms would improve continuously so that a regular intake of analgesics could be avoided. However pain intensity and pain duration differed between surgical procedures in our study. Especially patients undergoing back or joint surgery appeared to be impaired due to pain up to 6 months postoperatively. Consequently, in our sample, about 40 % of the patients after back surgery reported the intake of analgesics 6 months post-surgery, and 13.6 % of these patients even indicated the intake of opioids on a regular basis.These results are unexpected and show an unsatisfying result of the surgical intervention in terms of pain reduction. Moreover, the long-term intake of opioids in non-cancer pain is not supported by recent clinical practice guidelines , since oPossible explanations for the prolonged intake of analgesics after surgery may be an uncritical prescription of opioids or uncontrolled self-medication with analgesics. In patients undergoing spine surgery, psychiatric co-morbidity may be a risk factor for continued postoperative opioid intake, especially if opioids were already used prior to surgery . Also inMore effective pain management strategies already before and after surgery may provide improved surgical outcomes. This may contribute to a better quality of life  and may Cognitive and behavioral strategies in combination with individualized postoperative rehabilitation programs may also contribute to reduce the patients’ burden of pain and provide better surgical long-term results. Avoiding fear of movement and decreased physical function has already shown to be an important aspect e.g. in patients following lumbar spine surgery for degenerative conditions .Some limitations of the study should be considered. For the follow-up period, a longer observational time (e.g. up to 1 year) may have been reasonable in order to evaluate patients with a late improvement of pain symptoms. In addition, during the follow-up period no physical examination was performed in order to evaluate the functional improvement after surgery. Therefore, we could not state on functional success of surgery after physical therapy and rehabilitation programs. Furthermore, we did not discriminate whether the patients with urological surgery received a curative or a palliative intervention. However, since these patients reported the lowest pain levels in comparison to the other groups, before and after surgery, this aspect was not further investigated.In conclusion, these data reveal that a significant number of patients suffers from pain and need analgesic medication, even opioids, up to 6 months after surgery. The treatment of ongoing pain after surgery is still an important challenge. The need of preventive therapies should be considered for example in patients with neuropathic pain or patients with chronic opioid use. Besides the evaluation of predictive factors for ongoing postoperative pain and the identification of patients at risk, the improvement of postoperative pain management strategies after discharge should be subject of further research.


Outcomes after total knee (TKA) and hip (THA) arthroplasty are often generalized internationally. Patient-dependent factors and preoperative symptom levels may differ across countries. We compared preoperative patient and clinical characteristics from two large cohorts, one in Switzerland, the other in the US.Patient characteristics were collected prospectively on all elective primary TKAs and THAs performed at a large Swiss hospital and in a US national sample. Data included age, sex, education level, BMI, diagnosis, medical co-morbidities, PROMs (WOMAC pain/function), global health (SF-12).Six thousand six hundred eighty primary TKAs (US) and 823 TKAs (Swiss) were evaluated. US vs. Switzerland TKA patients were younger (mean age 67 vs. 72 years.), more obese (BMI ≥30 55% vs. 43%), had higher levels of education, more cardiac disease. Swiss patients had lower preoperative WOMAC pain scores (41 vs. 52) but pre-operative physical disability were comparable. 4,647 primary THAs (US) and 1,023 THAs (Swiss) were evaluated. US vs. Switzerland patients were younger (65 vs. 68 years.), more obese (BMI ≥30: 38% vs. 24%), had higher levels of education, more diabetes. Swiss patients had lower preoperative WOMAC pain scores (40 vs. 48 points). Physical disability was reported comparable, but Swiss patients indicated lower mental health scores.We found substantial differences between US and Swiss cohorts in pre-operative patient characteristics and pain levels, which has potentially important implications for cross-cultural comparison of TKA/THA outcomes. Reports from national registries lack detailed patient information while these data suggest the need for adequate risk adjustment of patient factors. Osteoarthritis (OA) of the knee and hip are the most rapidly rising musculosketetal conditions among adults as reflected in the increasing demand for total knee and hip arthroplasties  , 2. In tTotal joint arthroplasty (TJA) is currently the most effective treatment of endstage hip and knee OA. Because surgeons use similar implants internationally, the outcomes of TKA and THA, including patient-reported outcome measures (PROMs), complication rates, and implant survival, are often generalized across countries. Existing research has shown that these outcomes are in part dependent on the patient’s preoperative characteristics –14. HoweOur objective was to describe and compare preoperative TKA and THA patient characteristics from two large prospective cohorts, one in Switzerland (CH) and the other in the United States (US). If significant differences in patient risk factors are detected, this will support the need for risk-adjustment prior to future international comparisons of outcomes.Patient characteristics were collected prospectively on all elective primary TKAs and THAs performed (1) at a large University hospital in Geneva, Switzerland between January 2010 and December 2012 and (2) in FORCE-TJR, a diverse, national sample of more than 130 surgeons in the US between May 2011 and December 2012.Swiss patients included in this study are part of two registries at the Division of Orthopaedic and Trauma Surgery of the Geneva University Hospitals, Geneva, Switzerland: (1) the THA registry prospectively enrolling all patients undergoing THA since 1996; and (2) the TKA registry prospectively enrolling all patients undergoing THA since 1998. The registries are approved by the local Ethics committee. The institution is one of the largest Orthopaedic and Trauma Surgery centers in Switzerland and the only public hospital of the Canton Geneva serving a population of 500,000 inhabitants. The institution treats patients with public insurance (about 85% of the patients operated upon for TJA) as well as those with private insurance (about 15%). Switzerland has universal compulsory health care coverage. The patients in the two registries were comparable in age and sex-distribution to the Swiss population undergoing hip or knee replacement .FORCE-TJR  is a prospective, national total joint arthroplasty (TJA) cohort centered at the University of Massachusetts Medical School. Patients are enrolled from more than 130 orthopedic practices distributed across 22 states in the United States with diverse geography , ownership , and varied surgical volume to ensure inclusion of diverse patients and surgeon practices [In Switzerland, information on baseline patient characteristics (exposure) was obtained preoperatively on: age at operation; sex; education level (years of schooling in three categories); Body Mass Index (BMI); diagnosis (primary or secondary osteoarthritis as defined by the surgeon); and medical co-morbidities  were routinely obtained from the anaesthesia report and discharge summary. In the US, these same data were recorded at the time surgery was scheduled based upon the patient-report and surgeon records. The US registry did not record secondary osteoarthritis.Patient-reported outcome measures  were obtained by questionnaires sent to the patients 14 days (Swiss) and 1–2 months (US) prior to surgery. Geneva used a reduced form of the Western Ontario McMaster Universities (WOMAC) pain and function  and a glData missingness was assessed in both cohorts. Complete data were available for 80% of patients in the Swiss cohort and 92% for the US. The one exception was education level because education was not assessed in the early years of the Swiss cohort, but was complete in the later years.We calculated differences in proportions and their 95% confidence intervals (CI) to compare categorical variables, and mean differences and 95% CIs to compare continuous variables. In addition, preoperative score differences were assessed using effect sizes. Effect sizes were calculated as mean unadjusted difference divided by the pooled SD of the corresponding mean scores. Effect sizes of 0.2, 0.5, and 0.8 are regarded as small, medium, and large degrees of difference, respectively . For theOverall, 6,680 primary TKAs from the US cohort and 823 primary TKAs from the Swiss cohort were included (see baseline characteristics: Table 2) with the US having significantly more obese class I  and class II patients . Patients in the US reported cardiac disease more often, despite a younger mean age. With respect to preoperative scores, patients in the US had higher WOMAC pain scores (52 vs. 41 points) indicating significant knee pain in both countries, but less knee-specific pain at time of TKA in the US. The effect size was clinically relevant (0.57). While WOMAC function scores in both countries indicated significant impairment, knee-specific function scores were higher in the US (52.1 vs. 44.8). Pre-operative overall physical disability as measured by the general health questionnaire (SF) was reported in both countries, (Swiss 34.5 vs. US 32.7). The mental component score of the SF was lower in the Swiss cohort (effect size 0.56).Patients undergoing primary TKA in the US compared to those in Switzerland were significantly younger . The mean BMI differed between the two registries (31.5 vs. 29.6 kg/m2) with the US having more obese class I  and class II patients . Patients in the US had also more often diabetes, despite a younger mean age. With respect to preoperative scores, patients in the US had higher WOMAC pain scores (48 vs. 40 points) indicating less hip-specific pain at time of THA. The effect size was clinically relevant (0.43). WOMAC function scores were also higher in the US indicating slightly less functional impairment due to hip OA. Marked pre-operative overall physical disability on the general health questionnaire (SF) was reported in both countries,(US 31.3 vs. Swiss 33.4). The mental component score of the SF was lower in the Swiss cohort (effect size 0.50).Patients undergoing primary THA in the US compared to those in Switzerland were significantly younger . The mean BMI differed between the two registries  Fig. . For THAIn both the US and Swiss patients, higher BMI was associated with greater pre-operative pain and poorer function (lower WOMAC scores) for both TKA and THA Fig. . No statIn both the US and Swiss patients, lower education was associated with greater pre-operative pain (lower WOMAC scores) for both TKA and THA Fig. . PatientIn both the US and Swiss patients, poorer emotional health (low MCS) was correlated with greater pre-operative pain and poorer function Fig. . This reAt the time of primary total knee and hip arthroplasty, clinically important differences in age, education level, obesity prevalence, medical comorbidities, preoperative pain levels and emotional health were observed between the US and Swiss cohorts. The level of functional impairment at the time of TKA and THA reflected significant, and similar, disability in both countries. Because existing research documents that implant longevity, post-operative complication rates, and improvement in pain and function after TJA vary by patient characteristics, these data suggest that future cross-national TJA outcome comparisons should address pre-TJA patient differences prior to drawing conclusions –14.Obesity is a well-known and important risk factor for short- and long-term complications and a threat to prosthesis survival , 13. TheObesity is also known to be associated with younger age at the time TJA is performed . We founWhile patients in the US had greater BMI, the mean pain score among TJA patients in the US was less than the pain score reported in Switzerland. However, prior research has documented that greater BMI is associated with greater arthritis pain , 37. ThiOnly one study evaluated the association between education and preoperative pain and function levels  prior toDespite the younger age in US patients, the prevalence of comorbidities  was greater. Diabetes and cardiac disease are both associated with obesity and with increased short-term post-TJA complication rates , 11, 14.In summary, the greater prevalence of obesity and medical comorbidities, plus a younger mean age, potentially increase the risk for complications and revisions among the US patients, as compared to the Swiss. However, the Swiss reported a much higher proportion of patients with a low level of education, higher pain levels and poorer emotional health at the time of surgery. These differences should be considered in future cross-cultural comparisons of short and long-term outcomes after TJA.Few prior studies have evaluated differences in patient risk factors across international patient groups. In 2004, Lingard and colleagues evaluated the predictors of pain relief and functional gain after TKA in the US, England, and Australia . While tSurgeons, policy makers, and implant manufacturers rely on national registry reports for comparative implant information. Registry reports as those from the Scandinavian countries, the United Kingdom, or Australia present implant survival within age and sex sub-groups, and identify differences in implant survival by these patient attributes, While the United Kingdom, Sweden, the Netherlands, and New Zealand implant registries are now collecting PROMs , 53, 54 While we carefully pre-defined measures to assure comparable data, there are possible measurement limitations. First, both countries are dependent upon documentation practices for medical comorbidities and it is possible that the difference between the US and Switzerland is related to differences in documentation. For example, the US database lacked documentation of secondary OA, while the Swiss registry was able to differentiate primary and secondary OA. Second, different methods were used to collect and score patient-reported outcomes . However, previous psychometric research documents that the scores are comparable within SF versions and between the WOMAC and the KOOS. Finally, while this report is based on a sample of patients from the US and Switzerland, the respective registries have documented that the demographics of participating patients are comparable to the total population with health care coverage in these countries/regions and both cohorts include diverse surgeons.Clinically important differences in BMI, age at surgery, medical comorbidities, and preoperative pain and emotional health as well as differences in education level were observed between the US and Swiss cohorts before primary total knee and hip arthroplasty. The level of functional impairment at the time of TKA and THA reflected significant disability in both countries. The observed differences may result in differences in clinical outcomes, and complication and revision rates. Cross-cultural comparisons of TJA outcomes should consider risk-adjustment for these variables prior to making conclusions about apparent differences in outcome. Future studies will evaluate post-TJA outcomes and test the role of risk-adjustment prior to making these comparisons.


Chronic pain (CP) and sleep disorders (SD) are highly prevalent in the general population. However, comprehensive data regarding the prevalence and characteristics of pain and SD in primary care are rare.N = 578 patients N = 570 were included within 8 weeks . Sociodemographic data, Insomnia Severity Index (ISI), and parts of a self-report questionnaire for pain  were recorded and additional medical information  was gathered from the patient charts. From n = 189) suffer from CP (pain ≥ 6 months) and 29.1% (n = 166) from SD. 45.5% of the CP patients suffer from SD and 26.5% from clinical insomnia (ISI ≥ 15). SD  and older age  were significantly associated with pain experience. Of the total sample, 33.2% ( About a quarter of CP patients suffer from clinical insomnia. The suggested bidirectional relation should be considered during comprehensive assessment and treatment of patients. Chronic pain (CP) and sleep disorders (SD) have become two of the most common symptoms reported by primary care patients. The prevalence of CP ranges from 10 to 40% –8). CP iThere is limited but growing epidemiological information on the prevalence of CP and comorbid SD in primary care. In clinical settings SD have been found to impact 50–88% of CP patients , 26. VicThe presence of comorbid SD in patients with diabetic peripheral neuropathy and postherpetic neuralgia may even predict substantial pain relief in response to pain treatment with pregabalin .Patients with several SD, such as obstructive sleep apnea syndrome (OSAS)  and restParticipants were patients of a general practice in Austria. In this practice, patients are treated by a licensed general physician who underwent a qualification programme for psychosomatic and psychotherapeutic medicine  at the time of the study. The practice is the only general practice for a relatively large rural region where mainly workers and agriculturalists live.Within eight-week duration (06/01 to 07/24 2015) every patient of the general practice was asked to participate. The study nurses screened all potential participants for their eligibility and their level of cooperation in order to raise the responder rate. Subjects who were unable to complete the questionnaires due to linguistic barriers or serious physical or psychological health issues and patients younger than 10 years were excluded. After the initial information session all subjects were provided with questionnaires in the doctor's waiting room prior to the consultation. The following questions regarding pain and sleep disorders were included: “Do you suffer from pain/sleep disorders?” If this was answered by “yes” subjects were asked to proceed answering the relevant questions. In case patients did not know how to answer a question, the study nurses gave explanations.Pain was assessed according to the Multidimensional German Pain Questionnaire (Deutscher Schmerzfragebogen (DSF) ). The itSelf-reported level of education was assessed by using 4 response options. We asked for the highest educational attainment. Employment status was defined by using a 3-point categorical variable. Job seekers, person doing family work, and retired persons were assigned as “unemployed.” We categorized worker, piece worker, employees, self-employed people, apprentices, volunteers, and internships as “employed.” Scholars and students were categorized as “in education.” The specific categories of education as well as the ones of employment status can be seen in The current use of prescribed pain and sleep medication was gathered from the patients' charts. The coding of the medication as medication for pain or medication for sleep was done by A.G. According to the “Pain ladder," or analgesic ladder, created by the World Health Organization (WHO) , nonopioSD were assessed by the Insomnia Severity Index (ISI), a brief self-report questionnaire consisting of seven items. Each item has to be rated on a five-point Likert scale, ranging from 0  to 4 (extremely). The items are problems initiating sleep, problems maintaining sleep, early awake, satisfaction with current sleep patterns, impact on daytime quality of life due to SD, noticeability of sleep problems by others, distress or worry caused by SD, and interference with daytime functioning. Total scores range from 0 to 28. Higher scores indicate a greater insomnia severity . The psychometric properties are considered to be sound , 55.The study was conducted in accordance with the Declaration of Helsinki and approved by the local ethical committee of the Danube University of Krems.Patients were informed about the voluntary nature of participation and informed consent was obtained from each subject. If participants were younger than 18 years also parents had to agree. This study was conducted independently of any institutional influence and was not funded externally.N, n), percentages (%), means (M), and standard deviations (Std) were calculated as descriptive statistics; Chi-squared tests were performed to compare men and women. Individuals were excluded from the statistical analysis of a variable if they had a missing value in this given variable.The statistical analyses were performed with SPSS 23.0. Frequencies . We used standard stepwise backward model selection procedures based on AICc  for idenN = 570  patients participated in the study. This equals a response rate of 98.6%. The mean (Std) age was 50.8 (±18.7), for women 50.8 (±18.8) and for men 50.9 (±18.6) years. The majority attended compulsory school and apprenticeship . About half of the patients were employed . The mean of the body mass index in both genders is slightly increased. Not medicated were 67.9%, 22.6% took medications for pain, 5.4% received medication for sleep, and 3.2% were medicated for both pain and sleep. Further results for pain are summarized in A total of n = 238 (41.8%) answered yes to the question “do you suffer from pain?” indicating pain experiences . Pain duration of at least 6 months (CP) was reported by n = 189  and n = 33 (5.8%) of the total sample suffered from a clinical insomnia  also reported SD. Of the n = 86 patients with CP and SD, n = 83 also completed the ISI and n = 22 (26.5% of n = 83) had a clinical insomnia (ISI ≥ 15). One hundred and sixty-six patients of the total sample (29.1%) answered yes to the question “do you suffer from sleep disorders?”  and SD . SD was significantly associated with pain experiences .We include 567 individuals in the full model. The full model includes age, gender, BMI, employment status, education and sleep disturbances as correlates of experience of pain. After the stepwise reduction of variables the final model includes age .Older age was associated with pain experience also significantly (This study underlines the high prevalence of CP and SD in primary care. 33.2. % suffered from CP. Out of all participants 29.1% reported SD. 26.5% of CP patients suffered from clinical insomnia. These findings confirm results from previous studies , 36. In In our study SD and older age were significantly associated with pain as already reported . EmploymWe found a higher prevalence in patients suffering from initiating sleep, maintaining sleep, early awake, and dissatisfaction with sleep in comparison to Baker et al. . The mosThe results did not confirm existing evidence, that women experience chronic pain more often than men , 67. As SD are often overlooked in CP patients . This isGabapentin and pregabalin are also often used to treat CP and cooccurring SD , 75, 76.A variety of psychological interventions have been found to be effective in both pain treatment –84 and iThe results of our study have to be interpreted with respect to its limitations. The generalizability of the results is limited as only one general practice took part in the study. Yet, some aspects speak for the generalizability of the results. First, patients were treated under the conditions of routine. Second, the practice is the only general practice in a relatively large rural region. Moreover, it is important to note that the sample is based on a cross-sectional design, which does not allow causal inferences.Additionally, we did not assess psychiatric conditions, which are frequently associated with SD and pain , 88. AnoComprehensive management of CP and SD in primary care requires an individualized assessment and treatment approach. A shift from predominantly biomedical strategies to a more biopsychosocial perspective would raise treatment outcomes. SD should be systematically evaluated in CP patients in primary care settings based on the reported high cooccurrence. A proactive diagnostic approach for these persons is needed to achieve accurate information and treatment. Coordinated multidisciplinary and interdisciplinary care has a high potential to provide this. The high influence on personal life-quality and health care costs make it important that increased efforts in experimental and clinical research are made. The aim of these efforts should be a translationally meaningful understanding of the mutual impact of CP and poor sleep.


Despite the success of total knee arthroplasty (TKA) in reducing knee pain and improving functional disability, the management of acute postoperative pain is still unsatisfactory. This study was aimed to quantitatively analyze the possible correlations between inflammatory cytokines, muscle damage markers and acute postoperative pain following primary TKA.Patients scheduled for unilateral primary TKA were consecutively included, the serial changes of the numerical rating scale (NRS) at rest (NRSR) and at walking (NRSW), serum inflammatory cytokines and muscle damage markers were assessed before surgery (T0) and at postoperative day 1, 2, 3 and 5 ; while pain disability questionnaire (PDQ) and synovial fluid inflammatory cytokines were evaluated at T0. The correlations between inflammatory cytokines, muscle damage markers and pain scores were examined, and Bonferroni correction was applied for multiple comparisons.p < 0.05). The NRSR was positively correlated with serum PGE2, IL-6, and CK at T1; the NRSW was positively correlated with serum CRP at T1, with PGE2 and IL-6 at T1 to T3, with CK at T2 and T4, and with Mb and LDH at T1 to T4 . Meanwhile, positive correlations were observed between preoperative NRSW and synovial fluid PGE2, IL-6, IL-8, or TNF-α, as well as between PDQ and PGE2 , but no associations between postoperative pain scores and preoperative synovial fluid cytokines was found . Additionally, the NRSR at T1 and T2, and NRSW at T1 to T4 were positively correlated with body mass index .Ninety six patients were included for serum markers and pain evaluations at T0-T4, while 54 (56.25%) for synovial fluid cytokines at T0. The NRSR at T1 and T2 were positively correlated with preoperative NRSW, while the NRSW at T1 to T4 were positively correlated with preoperative NRSR, NRSW and PDQ  and markers  may serve as the targets for developing novel analgesic strategies.The online version of this article (doi:10.1186/s12891-017-1597-y) contains supplementary material, which is available to authorized users. A growing prevalence of knee osteoarthritis (OA), one of the most common age-related knee diseases characterized by cartilage degradation leading to progressive joint pain and disability , 2, is eIt is commonly known that the body mass index (BMI), gender and surgical approach are associated with acute postoperative pain after TKA –19, and To address these questions, we first examined the serial changes of acute postoperative pain scores, serum and synovial fluid inflammatory cytokines, and serum muscle damage markers in patients with severe knee OA before surgery and in subsequent periods after primary TKA in this study. Then, we quantitatively investigated whether the inflammatory cytokines and muscle damage markers were significantly correlate with acute postoperative pain.From October 2014 to December 2015, consecutive patients were evaluated for primary knee OA and scheduled for a TKA at the Department of Orthopedic Surgery, West China Hospital, Sichuan University. Patients eligible for this study should be: (1) more than 18 years old, and able to understand the nature of this study (informed consent); (2) without any infectious, psychiatric or neurologic pathologies ; (3) with a diagnosis of OA with a severity grade ≥ 3 according to the Kellgren-Lawrence (KL) classification , and witAll procedures performed in this study were approved by the Ethical Committee of West China Hospital, Sichuan University, and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Informed consent was obtained from all participants included in this study.All patients were classified according to the ASA  scoring system and underwent general anesthesia with same anesthesia protocols by a same senior anesthetist. All surgeries were performed by the same senior joint surgeon (Bin Shen), who had performed more than 1000 TKAs, through the standard medial parapatellar approach in the same laminar air flow operating room, and posterior stabilized total knee prosthesis system  was used in all included patients. A pneumatic tourniquet was used in all patients, inflating before skin incision and releasing after prosthesis placement, and a suction drainage was indwelled before suture and removed on the first morning after surgery. All patients began ambulation on the postoperative day (POD) 1. As an alternative multimodal analgesic protocols, all patients were sequentially treated with intravenous parecoxib (40 mg/q12h), the first injectable cyclooxygenase-2 (COX-2) selective inhibitor with approved indication of postoperative pain , for theJoint pain at rest (supine) and at walking  were assessed 24 h before (T0), 24 h after , 48 h after , 72 h after  and 5 days  after surgery by 2 investigators using the numerical rating scale  . Pain diVenous blood samples were collected at T0 - T4, and synovial fluid specimens were collected before exposure of the capsule intraoperatively (considered as preoperative sampling). The levels of inflammatory cytokines, including ESR, CRP, PGE2, IL-6, IL-8 and TNF-α, and muscle damage markers, including Mb, Cre, CK, LDH and AST, in serum were measured by the Department of Laboratory Medicine of our hospital certified by the College of American Pathologists. Additionally, PGE2, IL-6, IL-8 and TNF-α in synovial fluid were detected as well.t-test for normally distributed data and Mann-Whitney U-test for non-normally distributed data, while comparisons among three groups  were conducted using the one-way analysis of variance (ANOVA) with post-hoc analysis for normally distributed data, while Kruskal-Wallis H and Mann-Whitney U tests for non-normally distributed data. Spearman’s rank-based correlation coefficient was used to quantify the correlations between inflammatory cytokines, muscle damage markers and pain scores, as well as between BMI and pain scores. A p-value <0.05 was considered to indicate statistical significance. Since 15 markers  were assessed, the statistical significance for multiple correlations between inflammatory cytokines, muscle damage markers and pain scores were further evaluated using the conservative Bonferroni p value (0.05/15 = 0.003) to control the family-wise error rate.The demographics, operative information, NRS scores, values of inflammatory cytokines and muscle damage markers were collected. All statistical analyses were performed using the Statistical Package for Social Sciences (SPSS) software for Windows, version 22.0 . All continuous data were checked for normality first using Kolmogorov-Smirnov and Shapiro-Wilk tests. Comparisons between two groups  were conducted using the Student 2. The mean ASA was 1.75 ± 0.68, incision length was 15.21 ± 0.62 cm, operative time (from skin incision to the end of skin suture) was 58.20 ± 4.40 min, and the length of postoperative hospital stay (LPHS) was 7.11 ± 1.84 days. There was no significant differences in these characteristics between male (n = 18) and female (n = 78) patients. Additionally, synovial fluid inflammatory cytokines were detected in 54 patients  tended to report higher NRS than overweight  and normal weight  patients, although not all of the differences were statistically significant , while postoperative NRSR at T1 and T2 were positively correlated with preoperative NRSW . These results remained significant even if after adjusting for multiple comparisons . Furthermore, the preoperative NRSW was positively correlated with NRSR and PDQ , while no significant correlation between preoperative NRSR and PDQ was found.The serial changes of NRS pain scores following primary TKA are shown in Fig. 2 , n = 5) ant Fig. . Associap < 0.003, with Bonferroni correction). Postoperatively, the NRSR was positively correlated with PGE2 and IL-6 at T1; and the NRSW was positively correlated with CRP at T1, and with PGE2 and IL-6 at T1 to T3 .The serial changes of serum inflammatory cytokines are shown in Fig. n = 54) were 43.73 ± 17.85 ng/ml, 128.29 ± 104.2 pg/ml, 41.74 ± 21.58 pg/ml and 22.44 ± 11.34 pg/ml, respectively. Associations between synovial fluid inflammatory cytokines and pain scores are shown in Table p < 0.003); while no significant correlations between preoperative NRSR and cytokines was found . Furthermore, there was also no significant correlations between postoperative NRS, both NRSR and NRSW at T1 to T4, and preoperative synovial fluid cytokines . Additionally, the preoperative PGE2, as well as IL-6, in serum and synovial fluid were also positively correlated .The overall mean values of preoperative PGE2, IL-6, IL-8 and TNF-α in synovial fluid (p = 0.001), while no correlations between NRS and muscle damage markers was observed . Postoperatively, the NRSR was positively correlated with CK at T1 (p < 0.001); the NRSW was positively correlated with Mb and LDH at T1 to T4, and with CK at T2 and T4 .The serial changes of serum muscle damage markers are shown in Fig. r = 0.56, 0.80, and 0.37, respectively; and all p < 0.001). Meanwhile, the NRSW at T1 to T4 , as well as the NRSR at T1 and T2 , were also positively correlated with BMI.Because the obese patients tended to report higher NRS than overweight and normal weight patients (see above), the correlations between BMI and pain scores were further evaluated. As a result, preoperative NRSR, NRSW and PDQ were positively correlated with BMI  and TNF-α, presented in serum and synovial fluid in OA pathogenesis , 38, andESR is a non-specific hematological marker routinely used as an indirect parameter of increased acute phase reactants, and CRP is a major acute phase reactant and produced by the liver in response to inflammation, infection, malignancy or tissue damage . HonsaweWe further quantitatively analyzed the correlations between muscle damage markers and acute postoperative pain following primary TKA, and identified that Mb, CK and LDH were the key markers in systemic circulation which positively correlated with acute postoperative pain. Muscle damage could occurred not only intraoperatively, but also postoperatively. The medial parapatellar retinacular incision and release of medial collateral ligament (MCL) were inevitable in TKA, and contribute to the intraoperative muscle damage. Niki et al. reported that the levels of muscle-related enzymes were affected by the degree of medial release for appropriate soft-tissue balancing . Despite2 have a negative influence on the outcomes of primary TKA [2 (n = 53), in which only 5 were obese, the unbalanced sample size might introduce a bias, and further studies with more subjects and appropriate BMI constitution were needed to further illustrate the effects of BMI on acute postoperative pain after primary TKA.In this study, obese patients tended to report higher pain scores than overweight and normal weight patients, and the rest pain at POD1 and POD2, as well as the walking pain at POD1 to POD 5, were positively correlated with BMI. Although these results further supported our previous finding that a BMI ≥ 30 kg/mmary TKA , but whemary TKA . MoreoveAdditionally, although the overall walking pain was more severe than rest pain, some patients reported a more severe rest pain than walking pain in the same day. There is only one relative study, by Lunn et al., reported that acute postoperative pain at rest and during hip and knee flexion after TKA was significantly reduced 5 min and 20 min after walk compared with that before walk, and pain was further reduced during the second walk compared with the first walk . We asseHowever, several limitations must be taken into account in this study. Firstly, the subjects included in this study were confined to OA patients, and therefore it could not be generalized to other types of knee arthrosis, such as rheumatoid arthritis. Secondly, only 54 out of 96 (56.25%) patients had the synovial fluid data collected for preoperative analyses because the synovial fluid in some patients was too little or viscous and could not be detected, and the postoperative synovial fluid cytokines were also not assessed because the drainage tube was removed on the first morning after surgery. Thirdly, no control group, such as unicompartmental knee arthroplasty or minimally invasive approach, was established, and the joint function was not reported in this study. Finally, other confounding factors, such as fear or anxiety, articular nerves, implant type, and anticoagulant used for prophylaxis of postoperative venous thromboembolism –50, mighWe demonstrate in this study that serum inflammatory cytokines and muscle damage markers are positively correlated with acute postoperative pain following primary TKA, and the key serum cytokines  and markers  may serve as the targets for developing novel analgesic strategies.


Introduction Traumatic thoracolumbar burst fracture is a common pathology without a clear consensus on best treatment approach. Minimally invasive approaches are being investigated due to potential benefits in recovery time and morbidity. We examine long-term resolution of symptoms of traumatic thoracolumbar burst fractures treated with percutaneous posterior pedicle screw fixation.Methods Retrospective clinical review of seven patients with spinal trauma who presented with thoracolumbar burst fracture from July 2012 to April 2013 and were treated with percutaneous pedicle screw fixation. Electronic patient charts and radiographic imaging were reviewed for initial presentation, fracture characteristics, operative treatment, and postoperative course.Results The patients had a median age of 29 years (range 18 to 57), and 57% were men. The median Thoracolumbar Injury Classification and Severity Scale score was 4 (range 2 to 9). All patients had proper screw placement and uneventful postoperative courses given the severity of their individual traumas. Five of seven patients were reached for long-term follow-up of greater than 28 months. Six of seven patients had excellent pain control and stability at their last follow-up. One patient required revision surgery for noncatastrophic hardware failure.Conclusion Percutaneous pedicle screw fixation for the treatment of unstable thoracolumbar burst fracture may provide patients with durable benefits and warrants further investigation. Burst fractures at the thoracolumbar junction due to trauma are a common pathology.A retrospective clinical review was conducted of adult patients with spinal trauma who presented with thoracolumbar burst fracture from July 2012 to April 2013 at a single institution and were treated with percutaneous pedicle screw fixation. Electronic patient charts and radiographic imaging were reviewed for initial presentation, fracture characteristics, operative treatment, and postoperative course. Patients were contacted for long-term follow-up to assess resolution of pain and other symptoms from their injury.Patients were taken to surgery the day of or one day following injury. Pedicle screws were placed one level above and one level below the level of injury unless the fixed level would be adjacent to the thoracolumbar junction. In this case, the construct was extended an additional level. All pedicle screws were placed in the same fashion. After induction of general anesthesia, preoperative somatosensory evoked potentials were obtained and the patient was turned prone on a Jackson table. The back was prepped and draped in usual sterile fashion. The fluoroscopy unit was draped, and biplanar fluoroscopy was obtained of the injury to visualize and mark the appropriate pedicles. Paramedian incisions were made at the locations of the pedicles. Meticulous hemostasis was achieved with electrocautery. A Jamshidi needle was placed under fluoroscopy, then followed with a K-needle to confirm the trajectory of the pedicle screws . The Jamshidi needle was removed, and dilators were placed into the wound. The pedicles were then tapped and the pedicle screws were placed. Bilateral posterolateral fusion grafts of corticocancellous bone chips and demineralized bone matrix were placed adjacent to the construct. Wounds were then closed in layers as appropriate.Seven patients with thoracolumbar burst fracture were treated with percutaneous screw fixation. The cases are summarized inAll patients underwent surgery using the procedure described previously. Patients were instrumented either one or two levels above and below the level of the fracture at the surgeon's discretion. Only one intraoperative complication occurred: in the patient with multiple fractures, an anterior breach of the left L3 pedicle led to a hemorrhage. No intervention was required for the hemorrhage. Immediate postoperative imaging revealed no misplaced screws. The loss of height was reduced to a median of 5% (range 5 to 40%), and the Cobb angle was corrected to a median of 5 degrees (range 2 to 11 degrees). All four patients with preoperative canal compromise had significant resolution of the canal compromise. The median length of admission for our patients was 6 days (range 4 to 22). All radiographic factors remained stable at the last imaging follow-up .Five of the seven patients were reached via telephone to assess long-term resolution of pain and other symptoms. On average, the follow-up was 32.8 months (range 29 to 38) for these five patients. The last follow-up of the two patients who could not be reached via telephone was at the time of their last imaging follow-up at 10 and 6 months. Six of the seven patients had near-complete to complete resolution of their lower back pain.The patient with cauda equina syndrome had complete recovery of neurologic function without pain at last clinical follow-up. The one patient who required an open revision is still in significant pain and has been working closely with a pain specialist to control her symptoms.Currently, there is no consensus on the optimal treatment of thoracolumbar burst fractures. Due to improvements in spinal instrumentation technology and improved operator skill, multiple groups have argued for the use of percutaneous pedicle screw placement as part of the treatment for this pathology. As noted by Dhall et al in 2014, percutaneous pedicle screw fixation for unstable thoracolumbar fusion has not been examined in the literature with sufficiently long follow-up.Many studies have examined the use of percutaneous pedicle screw placement for thoracolumbar burst fractures. Shen et al compared posterior fixation versus nonoperative treatment and found no difference in functional outcome at 2 years, but short-segment fixation showed advantages in pain relief and kyphosis correction.Our series includes longer-term follow-up than most of the aforementioned studies. Our patients generally reported good pain and functional outcomes following their surgeries. One patient required a second surgery after T12–L2 pedicle screw fixation due to increased back pain resulting from a left L2 screw fracture, increased anterior wedging at L1, and focal kyphosis at T12–L1. The length of stay for our patients is longer than some in the literature, but this is likely due to the other traumatic injuries sustained by our patients in addition to their thoracolumbar injury.Several studies have investigated the use of balloon kyphoplasty for management of thoracolumbar burst fractures. One benefit of posterior fixation is the avoidance of risks associated with balloon kyphoplasty. In the Blondel et al and Korovessis et al series, 2 of 29 and 4 of 18 patients, respectively, had bone cement leakage without clinical sequelae.Postoperatively, six of the seven patients within our series had good outcomes during their follow-up. However, one patient with multiyear follow-up experienced hardware failure after 8 months of significant pain relief. Revision surgery provided stabilization for 38 months (with ongoing follow-up at this time), although she developed lower back and bilateral thigh pain after several months of pain relief when she became pregnant. This pain was attributed by a pain specialist to bilateral sacroiliac joint dysfunction, which was found in a prospective study to have an incidence rate of 6.3% in pregnant women.Ultimately, treatment of unstable thoracolumbar burst fractures with percutaneous pedicle screw fixation may be a viable strategy that requires further investigation to evaluate long-term outcomes and adverse effects in large cohorts. This investigation provides some evidence that such studies will be warranted due to the resolution of pain seen in the majority of our patients.


New drugs are increasingly used to induce analgesia during surgeries. This study compared the analgesic effects of paracetamol and magnesium sulfate.Sixty patients with American Society of Anesthesiologists (ASA) class I or II patients who were candidates for surgery of the lower limbs were randomly divided into three equal groups who were age and gender matched. Group 1 received paracetamol, and group 2, the magnesium sulfate during surgery and group 3 as the control. Pain intensities were measured and recorded using the Visual Analog Scale before surgery, in the recovery room, and 6, 12, and 18 hours after surgery. Pain intensities  were higher in the control group; 6, 12, and 18 hours after surgery compared to the paracetamol  and the magnesium groups , but the difference was not statistically significant.Paracetamol and magnesium sulfate were shown to have postoperative analgesic effects and reduce the quantity of narcotic use after surgery. Factors such as race, age, gender, expressing the pain, underlying diseases, level of knowledge of physicians and their fear of causing complications, usually can affect the pain in patients.2Pain is considered as the fifth vital sign that should be controled to prevent postoperative complications.3 One of medications that have attracted interest in pain control is intravenous use of acetaminophen (paracetamol).4 As intravenous injection of Non-Steroid Anti-inflammatory drugs (NSADIs) are unavailable in Iran , and based on complications reported by tramadol , paracetamol may be a suitable substitute. Paracetamol is an acetaminophen product that is soluble in water and can be injected intravenously when there is a need for a strong effect and rapid onset of analgesic action. Propacetamol is a form of paracetamol that is hydrolyzed to paracetamol in blood, with analgesic and antipyretic effects, without substantial complications at the recommended doses (1-2 g).5Several studies were conducted on pain reduction in operated patients, and attempts were made to quantify pain using Numeric Rating Scale (NRS) and Visual Analog Scale (VAS).6 Nowadays, use of opioids is one of the main pillars of pain treatment.7 However, because of its side effects, there is a need to find more effective products for relieving pain and reducing use of opioids. NSAIDs and acetaminophen, which are usually used as antipyretic drugs, can be utilized as substitutes for, or a complement to, narcotic drugs to control postoperative pain.8The mechanism of action of paracetamol is to suppress the synthesis of prostaglandins. Cyclooxygenase (COX) is the first enzyme in the production cycle of prostaglandins, and paracetamol blocks this cycle and acts as an analgesic.9 with many clinical applications in preeclampsia, eclampsia, bronchospasm, and control of muscle spasm in tetanus; while it is used as an antidysrhythmic drug too.10Considering the use of analgesia and the complications that may happen such as weakened respiration, physical dependence, and addiction, attempts were undertaken to introduce new drugs as analgesic substitutes, such as magnesium, which is a serum electrolytes and an N-methyl-diaspartate receptor antagonist9 Substances that block calcium channels and are N-methyl-diaspartate receptor antagonist can be effective in preventing the emergence of pain and in its control. Little information is available on the role of magnesium in elimination of pain in man, and the study that has been conducted on the analgesic effects of magnesium in man has controversial result.11Moreover, magnesium is known as a natural blocker of calcium channels with analgesic effects. Furthermore, some studies have indicated that magnesium can enhance the effects of morphine in patients with chronic pain, that it is an N-methyl-diaspartate receptor antagonist for ion channels, preventing central and peripheral sensitization resulted from environmental stimuli. It can terminate increased sensitivity that was previously appeared.12 Moreover, magnesium sulfate is used as a pharmacological agent in a range of clinical situations such as tachyarrhythmia, myocardial ischemia, asthma, preeclampsia, tocolysis and chills after surgery.13 The first mechanism explaining the analgesic effect of magnesium sulfate is its antagonistic effect on N-methy-diaspartate receptor. Stimulation of this receptor can increase the membrane permeability for potassium and calcium ions. Magnesium sulfate was shown to suppress the passage of electrical currents through membranes by suppressing the mentioned receptors.14The effect of magnesium were first recognized in treating arrhythmia and toxemia of pregnancy, and recently researchers have noticed its anesthetic and analgesic effects.15 The value and importance of magnesium sulfate as an adjuvant medication in anesthesia and as a inexpensive drug in postoperative analgesia has previously been confirmed.14 Considering complications caused by narcotics including bradycardia, respiratory depression, and fall in blood pressure, and as long-term use of narcotics is not always possible due to a dependence caused by it, anesthesia and pain specialists have searched for new products to reduce the use of narcotics for relieving pain in surgery that may be a combination of non-opioid pain- relieving compounds and narcotics.16Magnesium sulfate has specific effects on vascular dilatation that is mediated through releasing vascular endothelium derived nitric oxide (NO=nitric oxide).14-16 on various substances together with narcotics, but the required doses, the extent of pain reduction, and the possibility of using these substances in surgery have not been explained. Therefore, there is a need for research on the extent of analgesia caused by drugs of interest such as paracetamol (intravenous acetaminophen), and intravenous magnesium sulfate. This study compared the effect of intravenous paracetamol and magnesium sulfate before surgery on the extent of pain du. Ring and after surgery.Several studies were conducted in this relationThe convenient sampling method was used to select subjects from all patients referred to the Peymanieh Hospital in Jahrom, Southern Iran. All subjects were candidates for surgery in lower limbs and received spinal anesthesia and their blood pressure, respiratory and cardiac rates were recorded. There were three study groups. Group one received 15 mg of marcaine (3 ml of 0.5% marcaine) together with intravenous paracetamol (15 mg/kg body weight in 100 ml of 0.9% sodium chloride). Group two received 3 ml of 0.5% marcaine (15 mg/kg) together with 8 mg intravenous magnesium sulfate/kg body weight/hour until the completion of the surgery as an infusion dose. Group three, the control group, received 3 ml of 5% marcaine (15 mg/kg) together with 100 ml of normal saline as a placebo. It was estimated marcaine to be remained effective for about 2 hours. Twelve-lead electrocardiography was performed for all patients. The anesthesiologist used a 25 gauge spinal needle to inject the prepared solution in a sitting position. If the sensory block was inadequate, general anesthesia was induced, and the patient was excluded from the study. During the surgery, hemodynamic changes were measured every 5 minutes. Moreover, complications of spinal anesthesia including nausea, vomiting, fall of systolic blood pressure by more than 20% from the baseline, respiratory depression during surgery, and reduction in heart rate/minute by more than 20%, were recorded. If during surgery, drugs or measures other than routine care were required to eliminate complications and relieve pain, the patient was excluded from the study too. The inclusion criteria were (i) American Society of Anesthesiologists (ASA) class I or II, (ii) Not banned from undergoing spinal anesthesia, (iii) Not addicted to narcotics, (iv) Not taking psychiatric medications, (v) Not experiencing delirium, (vi) No history of hypertension, (vii) No history of heart problems, (viii) No drug allergies and (ix) older than 18 and less than 75 years of age. The exclusion criteria were (i) Allergies to drugs used in the study, (ii) Any unpredicted event during surgery endangering the patient’s life and hemodynamic status, (iii) Spinal anesthesia being changed to general anesthesia, (iv) History of alcohol abuse, recent use of tranquilizers, psychotropic and antipsychotic drugs, calcium channel blockers, and history of neuromuscular diseases, (v) Thyroidal disorders, history of any type of renal failure, underlying bradycardia (fewer than 60 heart beats per minute) and (vi) QRS interval prolongation (>0.12 second), QTc interval prolongation (>0.44 second).At the completion of surgery, when the patient was conscious, hemodynamic signs  were measured, and they were evaluated during 24 hours period after surgery for emergence of sensory motor complications. The nurses and the doctors provided identical care, which was customary in the ward, for all three groups, and all the analgesics that were routinely used in the ward were given to the patients of all three groups. Pain intensity was recorded four times, first in the recovery room and then 6, 12, and 18 hours after surgery to obtain average pain intensity. If any of the patients in the ward felt severe pain, pethidine was administered and the quantity was recorded in a questionnaire sheet. The placebo group did not receive any medications and if they felt pain, pethidine was prescribed and its amount was recorded in the questionnaire sheet. Information was analyzed using descriptive statistical indices such as means and percentages, and statistical tests including repeated measurement and ANOVA were performed using SPSS software . The average age of the subjects in the three groups was 36.6 years, while the majority were 20 years old. There were 23 female and 37 male participants: Seven females and 13 males in the control group, 8 females and 12 males in the paracetamol group, and 8 females and 12 males in the magnesium sulfate group. Thirty-two patients in the three groups underwent tibial surgeries and 28 for femoral operations. In the control group, 10 patients had tibial and eight femoral surgeries. In the paracetamol group, 10 members had tibial and 10 femoral operations. Finally, 10 subjects in magnesium sulfate group had tibial and 10 femoral surgeries.p>0.05). In the recovery room, the average pain intensy determined by VASD table was 1.20, 1.35, and 1.00 in the control, paracetamol, and magnesium sulfate groups, respectively. There were no significant differences between the three groups regarding pain intensity in the recovery room (p>0.05). Based on the VASD table, the average pain intensity was 7.10, 6.45, and 7.25 in the control, paracetamol, and magnesium sulfate groups, respectively, 6 hours after surgery. There were no significant differences between the 3 groups for average pain intensity, 6 hours after surgery (p>0.05). The pain intensity before surgery determined by VASD table showed that the average pain intensity before surgery was 6.60, 6.70, and 7.55 in the control, paracetamol, and magnesium sulfate groups, respectively. There were no significant differences between the three groups for pain intensity before surgery (p>0.05). Finally, based on the VASD table, the average pain intensity in the control, paracetamol, and magnesium sulfate groups were 4.10, 2.50, and 2.05, respectively. there were no significant differences between the 3 groups with respect to the average pain intensity, 18 hours after surgery (p>0.05). The comparison of pain intensity before surgery, in the recovery room, and 6, 12, and 18 hours after surgery in the three groups was shown in The mean of pain intensity 12 hours after surgery, as determined by VASD table, was 5.80, 4.15, and 4.55 in the control, paracetamol, and magnesium sulfate groups, respectively. There were no significant differences between the 3 groups for average pain intensity, 12 hours after surgery (p>0.05).The mean percentages of administerd narcotics in the control, paracetamol, and magnesium sulfate groups were 33.3% (30% pethidine and 3.3% morphine), 25% (pethidine), and 13.3% (pethidine), respectively. The difference between the three groups was not statistically significant. The comparison of respiratory changes in the 3 groups in the recovery room showed that the mean respiratory rate/minute was 18.05, 18.66, and 18.70 in the control, paracetamol, and magnesium sulfate groups, respectively. There were no significant differences between the three groups for respiratory rate/minute in the recovery room . The average number of heart rate/minute in the three groups in the recovery room was 81.20, 84.25, and 81.65, in the control, paracetamol, and magnesium sulfate groups, respectively. There were no significant differences between the three groups for average number of heart rate/minute (p>0.05). Nausea, vomiting, and any signs of itching were also determined in the recovery room. Nausea was observed in six patients in the control, in 2 patients in the paracetamol, and in 5 patients in the magnesium sulfate groups. The groups were not significantly different with respect to nausea in the recovery room (p>0.05). No instances of vomiting or itching were observed in any of the three groups. The groups were not significantly different for average systolic blood pressure in the recovery room (Our study showed that use of intravenous paracetamol (15 mg/kg body weight in 100 mm of 0.9% sodium chloride) could have analgesic effects in patients and reduce the required quantity of narcotics after surgery. Moreover, this research indicated that the use of magnesium sulfate (8 mg/kg body weight once every hour during the surgery) could have analgesic effects in patients and reduce the amount of narcotics after surgery, but the differences were not statistically significant. The scores on pain intensity in patients using the VAS system, and based on narcotic use after surgery, showed that paracetamol and magnesium sulfate could reduce the pain intensity, 6, 12, and 18 hours after operation, but there were no significant differences between the the 3 groups. Nevertheless, pain intensity in the paracetamol group, 12 after the surgery was lower than magnesium sulfate group. The pain intensity was lower in the magnesium sulfate group, 18 hours after the surgery when compared to the paracetamol group. Therefore, magnesium sulfate had longer analgesic effects in comparison to paracetamol. The two groups were not significantly different with respect to pain reduction. For comparison of the paracetamol and magnesium sulfate groups in relation to the quantities of narcotics used after surgery, the two groups were not significantly different, but the quantity of narcotics after surgery in the magnesium sulfate group was less than the paracetamol group.17Our findings revealed that magnesium sulfate resulted into a reduction in narcotics use after surgery when compared to paracetamol even the difference was not statistically significant. Scoring of pain by two groups receiving paracetamol and intravenous morphine after orthopedic surgery was previously undertaken. Comparison of the difference between two groups revealed no significant difference too similar to our study. The quantity of narcotic used in the paracetamol group was less in comparison to the control group, showing a decrease for narcotics in these patients.18 and these results were identical to our research. In another study conducted on the effects of acetaminophen and paracetamol on pain intensity in patients after orthopedic surgery, it was noted that scores given to pain intensity felt by patients decreased significantly, and the need for narcotics also declined significantly in comparison to the control group. These findings were the same as our study even their results denoted to a significant difference between groups.19In research carried out on the effects of paracetamol on pain intensity after appendectomy operation in comparison to pethidine, it was found that pain intensity in the paracetamol group was significantly less,20 In another study that was conducted by Amiundertaken on 60 patients undergoing spinal injury to compare the analgesic effects of tramadol together with paracetamol and tramadol, it was observed that the analgesic effect was greater in the paracetamol group.21 In all of the mentioned studies similar to ours, the number of injections and the total dose of narcotics used declined significantly. A study was carried out in Russia in 2002 on analgesic effect of paracetamol after surgery on 30 patients demonstrating that paracetamol reduced the pain intensity after surgery.22 In another research carried out on the postoperative effects of magnesium sulfate injection during inguinal hernia operation, it was found that pain intensity significantly decreased after surgery and the quantity of narcotics used after the operation in the magnesium sulfate group was less than the control group which is identical to our results.23The effects of intravenous magnesium sulfate on pain intensity after the surgery in 68 patients undergoing elective cesarean section under spinal anesthesia, magnesium sulfate could reduce the pain intensity even the difference was not statistically significant. However, the quantity of narcotics needed after surgery in the control group was greater compared to the magnesium sulfate group which is similar to our findings.24 The effect of magnesium sulfate on the quantity of needed narcotics in 81 patients after surgery was investigated and was shown that magnesium sulfate reduced pain intensity and the amount of required narcotics after surgery while these findings are the same as our results.25 A research conducted on 40 patients who were candidates for total hip joint replacement, the analgesic effect of magnesium sulfate was assessed and was demonstrated that the pain intensity and quantity of required narcotics were less in the magnesium sulfate group when compared to the controls similar to our study.26In a study on the effect of magnesium sulfate injection for postoperative pain in patients undergoing thoracotomy, it was reported that the scores given to pain intensity declined in the magnesium sulfate group and the quantity of needed narcotics in this group was less than the control group confirming our study.22-26 Reduced complications in the paracetamol and magnesium sulfate groups can be attributed to the less quantity of narcotics needed by these groups after surgery. Lack of complications in our study can be attributed to the low dose of injected narcotics and to the prescription of the anti-nausea drug metoclopramide at the start of surgery.In our research, complications such as suppressed respiration, vomiting, and itching were not reported in any of the patients, but nausea was observed in some patients of all three groups. However, no significant correlation was found. In previous studies, in most cases, side effects in the paracetamol and magnesium sulfate groups were not different from those in other groups but, in general, these side effects were fewer in the paracetamol and magnesium sulfate groups and no serious complications were seen in any of the groups.Our study indicated that intravenous paracetamol had postoperative analgesic effects and could reduce the number of injections and the total dose of injected narcotics. Therefore, intravenous paracetamol can be used as a suitable adjuvant anesthetic for narcotics. Moreover, intravenous magnesium sulfate had postoperative analgesic effect and reduced the number of injections and the total dose of injected narcotics too. Furthermore, magnesium sulfate had longer analgesic effects compared to paracetamol and caused greater decrease in the quantity of required narcotics compared to paracetamol, even the difference was not statistically significant. Another important point was that the average ages in the three groups were not significantly different, which increased the value of comparison of the variables among the three groups. In addition, the three groups were similar regarding gender.Paracetamol and magnesium sulfate were shown to have postoperative analgesic effects and reduce the quantity of required narcotics after surgery. So these drugs could be recommended to decrease the amount of required narcotics and can be used as adjuvant drugs to reduce pain.


Bilateral vestibulopathy (BVP) is a chronic condition in which patients have a reduction or absence of vestibular function in both ears. BVP is characterized by bilateral reduction of horizontal canal responses; however, there is increasing evidence that otolith function can also be affected. Cervical and ocular vestibular-evoked myogenic potentials (cVEMPs/oVEMPs) are relatively new tests of otolith function that can be used to test the saccule and utricle of both ears independently. Studies to date show that cVEMPs and oVEMPs are often small or absent in BVP but are in the normal range in a significant proportion of patients. The variability in otolith function is partly due to the heterogeneous nature of BVP but is also due to false negative and positive responses that occur because of the large range of normal VEMP amplitudes. Due to their variability, VEMPs are not part of the diagnosis of BVP; however, they are helpful complementary tests that can provide information about the extent of disease within the labyrinth. This article is a review of the use of VEMPs in BVP, summarizing the available data on VEMP abnormalities in patients and discussing the limitations of VEMPs in diagnosing bilateral loss of otolith function. Bilateral vestibulopathy (BVP) is a rare and chronic condition resulting from a loss or reduction of vestibular function in both ears , 2. As vDemonstration of vestibular loss has historically been sought by a caloric or rotational chair test, both of which assess the horizontal angular vestibulo-ocular reflex (VOR) , 7. MoreIn recent years, vestibular-evoked myogenic potentials (VEMPs) have become a widespread test of otolith function . CervicaCervical VEMP abnormalities in BVP were first reported by Matsuzaki and Murofushi , who tesSeveral early oVEMP studies reported absent BC oVEMPs in small series of patients, suggesting possible utricular involvement in BVP –23. Hower = 0.51)  , consistZingler et al.  found noA surprising frequency of preserved VEMPs has also been reported in patients with BVP combined with cerebellar atrophy. Marti et al. , 32 descThe dissociation of canal and otolith function is even more obvious in patients with bilateral vestibular loss due to large vestibular aqueduct syndrome. A recent article showed that many patients had bilateral canal paresis on caloric testing, but augmented AC cVEMPs and oVEMPs, with enlarged amplitudes and lowered thresholds compared to controls . HoweverOne reason for the canal-otolith dissociation in BVP relates to the diagnostic criteria. By definition, all of the patients have profoundly abnormal or absent horizontal semicircular canal function bilaterally as measured by the caloric and/or HIT. It is therefore to be expected that horizontal canal dysfunction is universal in BVP, while all other end organs may have lesser degrees of dysfunction , and congenital malformations (LVAS). As it is a rare condition and VEMPs are relatively new tests, there are few studies comparing sufficient numbers of patients with different etiologies. Alternately, factors relating to the VEMP test itself may also affect the rate of otolith abnormalities found in BVP.Due to the large range of normal VEMP amplitudes false negative responses may occur, i.e., responses fall in the normal range, but may be smaller than they would be without the effects of BVP. Unlike the vHIT, in which the obtained VOR gain is compared to an ideal of 1.0 , there iFalse positive  responses can also occur for several reasons. There is a well-documented effect of age on reflex amplitudes, which is greater for the AC cVEMP than BC oVEMP –44. For Vestibular-evoked myogenic potential studies have shown a range of otolith function in patients with BVP. This variability can be partly attributed to the heterogeneous nature of BVP but is also due to the nature of the VEMP tests and the large range of responses present in normal subjects. It is appropriate that VEMPs remain a complementary test in BVP: while not helpful to the diagnosis of BVP, VEMP-vHIT-caloric dissociations may prove useful in determining its etiology and provide information about the extent of disease within the labyrinth. They may also be helpful in monitoring disease progression and guiding rehabilitation. As vHIT and VEMPs become more widespread, we hope to see more large studies of BVP patients with different etiologies to better understand the effects of BVP on canal and otolith function.SR drafted and edited the manuscript. MW and RT edited the manuscript.The submitted work was not carried out in the presence of any personal, professional or financial relationships that could potentially be construed as a conflict of interest.


Similardesign study, language, and tables were found in a previously published article,“Botulinum toxin type A for neuropathic pain in patients with spinal cordinjury”, which appeared inVolume 79, Issue 4 of Annals of Neurology, without any attribution orcitation.The article, “A randomized controlled trial of botulinum toxin A for treatingneuropathic pain in patients with spinal cord injury”,


To quantify the influence of baseline pain levels on weight change at one-year follow-up in patients attending a National Health Service specialist weight management programme.We compared one-year follow-up weight (body mass) change between patient sub-groups of none-to-mild, moderate, and severe pain at baseline. A mean sub-group difference in weight change of ≥5kg was considered clinically relevant.Of the 141 complete cases, n = 43 (30.5%) reported none-to-mild pain, n = 44 (31.2%) reported moderate pain, and n = 54 (38.3%) reported severe pain. Covariate-adjusted mean weight loss (95%CI) was similar for those with none-to-mild (8.1kg (4.2 to 12.0kg)) and moderate pain (8.3kg (4.9 to 11.7kg). The mean weight loss of 3.0kg (-0.4 to 6.4kg) for the severe pain group was 5.1kg  lower than the none-to-mild pain group and 5.3kg  lower than the moderate pain group.Patients with severe pain upon entry to a specialist weight management service in England achieve a smaller mean weight loss at one-year follow-up than those with none-to-moderate pain. The magnitude of the difference in mean weight loss was clinically relevant, highlighting the importance of addressing severe persistent pain in obese patients undertaking weight management programmes. Obesity is a major public health issue affecting one in four adults in England . As suchClinically, pain has been implicated as an important barrier to weight loss  and the Wachholtz et al  found thThis is an analysis of an NHS clinical dataset of patients who attended a specialist weight management service in the North East of England from February 2013 to November 2014. To be referred to the specialist weight management service patients were required to meet the following admissions criteria of having a BMI of ≥40 or a BMI ≥35 with a significant co-morbidity such as diabetes or hypertension. Furthermore, patients were required to be registered with a local GP; aged ≥16years; with an ability to take charge of their dietary intake; assessed as “ready to change”; and have had previous attempts at weight loss either in primary care including community weight management programmes, exercise programmes or anti-obesity medication for a minimum of 6 months. Their GP needed to have completed a recent metabolic and endocrine assessment and could show that the patient’s underlying endocrine diagnosis was stable and any secondary causes of obesity excluded. Patients were excluded from referral to the specialist weight management service if they did not meet the admission criteria above, or if they had a suspected or diagnosed malignancy, were pregnant, or requiring post-bariatric care (unless previously known to the service). From the pre-existing patient database, to be included in this study, participants needed to have provided baseline and one-year outcome data. Ethical approval for this study was obtained from The School of Health and Social Care Research Ethics and Governance Committee at Teesside University (Reference number 074/14) and the Wales 7 National Research Ethics Committee (Reference number 14/WA/1050). The IRB waived the need for individual participant consent for medical records to be used in this study, and data was accessed anonymously.The specialist weight management service provides a multidisciplinary, biopsychosocial approach for morbidly obese patients.Patient treatment programmes consist of three main phases. The timing of these phases varied from patient to patient. In phase 1, patents initially receive a multidisciplinary team (MDT) assessment including consultation with a Dietician, Physiotherapist, Psychologist, Metabolic Physician/Endocrinologist, GP with a specialist interest in obesity management, and an individual care plan is generated. The individual care plan includes: an exercise and physical activity plan; outcomes expected for the individual; target weight; behavioural goals; modification of eating patterns; goals relating to lifestyle factors; changes in behaviour relating to triggers and barriers; food and activity diaries; tools and educational materials. In phase 2, patients move into group services and treatment according to their specific needs and care plan. During this phase a weekly drop-in and telephone support service is provided. Interactions with these elements of the service are recorded and shared with the patient’s Care Manager. In phase 3, patients are discharged from the service with details of the patient’s outcomes and an ongoing care plan sent to their GP; signposting to support groups; community weight management services and exercise groups for further weight loss and/or weight maintenance support.Whilst outcome measures within the specialist weight management service are collected at regular intervals this study includes only the baseline and one-year post baseline data. The primary outcome measure was weight (body mass) loss, which was measured using a weighing scales . Height was also recorded using a Leicester Height Measure (Mark 2) so that BMI could be calculated.how much bodily pain have you had during the past four weeks? and 2) during the past four weeks, how much did pain interfere with your normal work (including work both outside the home and housework)? The first question is rated on a 6-point Likert scale ranging from none to very severe, whilst the second question is rated on a 5-point Likert scale ranging from not at all to extremely. The raw score is then converted as a simple algebraic sum into a 0–100% scale value with higher scores representing higher pain levels [Pain was measured using the Short-form 36 (SF36) bodily pain subscale ,27. The n levels .The following additional participant characteristics were collected: sex, age, socioeconomic status and depression levels. Socioeconomic status was assessed using the Lower layer Super Output Area (LSOA) which is derived from the patient’s postcode. The LSOA was used to assign each patient an index of multiple deprivation, which was categorised into deciles with 1 being least affluent and 10 being most affluent. Depression levels were measured using the depression subscale of the Hospital Anxiety and Depression scale (HADs) .Individuals were categorised into none-to-mild, moderate, and severe pain sub-groups according to their baseline pain scores. The cut-off points used in this analysis were <50% mild pain, 50–69.99% moderate pain, and 70–100% severe pain . A generA sub-group difference in mean weight change was considered clinically relevant if it was ≥5kg. This was based upon the American Heart Association guidelines which state that reductions in weight of 2.5–5.5kg achieved through lifestyle interventions can reduce the risk of developing type 2 diabetes in overweight and obese individuals by 30–60%, while a reduction of 5-8kg can improve triglyceride levels and blood lipid profile .Data were obtained for 167 participants who provided baseline and one-year follow-up data. Of these, 26 had missing data and were thus excluded from the analysis. The descriptive characteristics for those with complete data and those with missing data are shown in Of the 141 complete cases, over the one-year period 52% of patients lost ≥5kg, which is a greater proportion than that expected due to typical within-subjects variation in weight . The adjCovariate-adjusted mean weight loss (95%CI) was similar for those with none-to-mild pain (8.1kg (4.2 to 12.0kg)) and moderate pain (8.3kg (4.9 to 11.7kg)), but was lower for the severe pain group (3.0kg (-0.4 to 6.4kg)) . There wThis is the first study to directly investigate the effect of persistent pain on weight loss in patients undergoing specialist weight management within the NHS. More than 95% of the patients reported persistent pain at baseline with more than a third of patients reporting severe pain. Our findings indicate that patients with severe pain at baseline lost less weight at one-year follow-up when compared to those with none-to-mild pain or moderate pain. There was no difference between the none-to-mild pain and moderate pain groups.-2). Other reasons may be to do with differences in study methodology. Masheb et al. [The findings of our study are broadly in keeping with Masheb et al.  who founb et al.  was a reb et al. .The clinical implication of our findings is that severe pain levels may be a considerable barrier to weight loss in those referred to specialist weight management services in the NHS by a magnitude of 5kg. Given the high prevalence levels of persistent pain in obese populations, especially in those with more severe obesity , the reaThis study has a number of limitations. This is a retrospective observational study, thus no claims of cause and effect can be made. While pain was measured using a valid and reliable questionnaire, pain characteristics such as location, duration and type of pain were not recorded. Thus, their potential role in weight loss was not explored. Whilst a number of important co-variates were adjusted for within the statistical model, some potentially important co-variates such as diet were not included. During the time period in which this data was collected, 837 patients were discharged from the specialist weight management service. Thus, data was only available for 19% of the patients at this clinic. As such, this sample may not be representative of patients attending NHS weight management services, reducing the generalisability of our findings. Additionally, the sample is small, which increases the risk of a type II error. However, the strength of this work is the use of a well-validated measure of pain and clinically established published cut-off values for none-to-mild, moderate and severe pain. Data on the location of the pain would have been useful contextual information but previous work suggests that it may be of limited relevance .In conclusion, patients with severe pain at the point of entry to an NHS specialist weight management service appear to lose less weight at one-year follow-up compared to those with none-to-mild or moderate pain. The magnitude of the difference is likely to be clinically relevant and highlights the potential gains in weight loss that might be achieved by addressing concomitant persistent pain in weight management services. There was no difference in weight loss between those who reported none-to-mild pain and moderate pain. These findings broadly support earlier findings in a sample of, predominantly male, US veterans , thus suS1 Appendix(XLSX)Click here for additional data file.


The incidence and impact of chronic inguinal pain after kidney transplantation is not clearly established. A high incidence of pain after inguinal hernia repair, a comparable surgical procedure, suggests an underexposed problem.Between 2011 and 2013, 403 consecutive patients who underwent kidney transplantation were invited to complete the Caroline Comfort Scale (CCS) and Visual Analog Scale (VAS) in order to assess the incidence of chronic inguinal pain and movement disabilities, complemented by questions regarding comorbidity during follow-up.n = 199) with a median follow-up of 22 months (IQR 12–30). In total, 90 patients (45 %) reported a CCS > 0 and 64 patients (32 %) experienced at least mild but bothersome complaints. Most inguinal complaints were reported during bending over and walking with a mean CCS score of 1.1 (SD ± 2.2) and 1.2 (SD ± 2.4), respectively. A high body mass index (BMI), delayed graft function, and the need for a second operation were associated with a higher CCS score on univariate analysis. Using multivariate analysis, only BMI (p = 0.02) was considered an independent risk factor for chronic inguinal pain.The response rate was 58 % (The incidence of chronic inguinal pain is a common though underexposed complication after kidney transplantation. More awareness to prevent neuropathic pain seems indicated. Kidney transplantation remains the preferred treatment in patients with end-stage renal disease and not only results in a better survival but also in an improved quality of life (QoL) , 2. QoL Inguinal herniorrhaphy, a surgical procedure located in comparable anatomical levels in the inguinal region, is known for its high risk 15–53 %) of chronic pain . Herein –53 % of A large Dutch study among surgeons and surgical residents showed a reduced understanding of inguinal neurologic anatomy and an underestimation of the chronic inguinal pain incidence after hernia repair . BecauseBetween 2011 and 2013, 403 consecutive patients who underwent kidney transplantation were invited to complete the questionnaires . These d®) intravenously or subcutaneously. A patient-controlled analgesia pump was occasionally used. Nonsteroidal anti-inflammatory drugs were avoided because of nephrotoxic side effects. The postoperative pain treatment during the first 24 h was evaluated by anesthetists.An oblique surgical incision was performed from the pubic bone through about two centimeters cranial to the superior anterior iliac spine. The internal and external oblique fasciae were closed by dissolvable polydioxanone sutures, and the skin was closed by staples. Postoperative pain management consisted of paracetamol and administration of piritramide , American Society of Anaesthesiologists (ASA) score, complications according to Clavien-Dindo classification (within 30 days after transplantation), type of graft, site of transplantation, need for re-intervention, need for transplantectomy, and allograft rejection. Comorbidity was determined by the age-adjusted Charlson Comorbidity Index (CCI), based on the previous medical history. The CCI is a weighted score which predicts the 1-year mortality of a patient, based on coexisting medical conditions and age .For completeness, we added general questions to the enquiry to assess potential confounding factors. For example, 90 % of diabetic patients develop polyneuropathy at some time and this could lead to bias . FurtherThe questionnaire consisted of the Carolina Comfort Scale 9), the Visual Analog Scale  , the Num, the Visχ2 test or Fisher’s exact test and presented as numbers or percentages presented as mean ± standard deviation (SD). Continuous variables were tested with the Student’s t test for normal distribution and the Mann–Whitney U test for skewed distribution and presented as median ± interquartile range (IQR).Categorical variables were analyzed by means of the p < 0.05. All statistical analyses were done with the Statistical Package for the Social Sciences .Linear regression method was used to perform univariate and multivariate analyses on factors associated with a higher score. Missing values were evaluated by Little’s MCAR test and, depending of level of significance, missing data were replaced by either expectation maximization technique (EM) or multiple imputation regression method (MI). Two-tailed P values were used throughout and significance was set at n = 24), median laparotomy (n = 12), incapability of reading Dutch or English (n = 6), mental retardation or neurological deficit (n = 11), and patients who underwent two kidney transplantations within the study period (n = 5). Of the 345 remaining patients, 199 patients returned the questionnaire (58 %) of which 82 were female (41 %) and 116 were male (59 %). The median follow-up was 22 months (IQR 12–30). In total, 86 % of participants completed the questionnaire resulting in 97 % of items being answered. In Table From 2011 to 2013, 403 consecutive patients underwent kidney transplantation. Based on before-mentioned exclusion criteria, 58 patients were excluded due to death during follow-up . In total, 90 patients (45 %) reported a CCS > 0 and 64 patients 32 %) experienced bothersome complaints (CCS ≥ 2) on one or more subcategories of the CCS. Bothersome movement impairments occurred in 54 patients (27 %). Most inguinal complaints were reported during bending over and walking with a mean CCS score of 1.1 (SD ± 2.2) and 1.2 (SD ± 2.4), respectively. Mean outcomes are shown in Fig. 2 % experp = 0.01), need of a second operation (p = 0.038), and DGF (p = 0.033) were associated with a higher CCS score. In multivariate analysis, BMI (p = 0.02) remained an independent factor associated with a higher CCS score. (Table p = 0.271).Using univariate analysis, BMI . Eleven percent of all patients used analgesics for inguinal complaints at time of completing the survey after a mean follow-up of 21.7 months (SD ± 11.3). Despite these possible confounding factors, no differences in incidence of chronic pain could be found during sensitivity analysis when excluding patients with diabetes, COPD, or prior inguinal surgery.The mean VAS score was 10 (SD ± 20.1) and mean NPRS was 1.2/10 (SD ± 2.0).p = 0.007). DGF was associated with a higher NPRS score (p = 0.032) All other factors, including BMI, were nonsignificant in both scales.Fifty-one percent of the patients had a VAS > 0 and 39 % had NPRS > 0 at the time of the survey. The age-adjusted CCI was associated with a higher VAS score , and allograft rejection was not associated with a higher score.Thirdly, because some patients already suffered from atypical chronic pain, this may have influenced our results. A previous study reported that the presence of preoperative pain is an independent factor for chronic pain after inguinal herniorrhaphy . HoweverA higher age-adjusted CCI score was associated with a higher VAS score and DGF was associated with a higher NPRS score. However, both scales are unidimensional and therefore do not seem the most suitable to use after kidney transplantation.A new prospective study should be performed to assess whether nerve identification in kidney transplantation is feasible and leads to a decrease in chronic pain.Chronic inguinal neuropathic pain after kidney transplantation is common and seems to have a similar etiology as observed in inguinal hernia repair. Detection of the inguinal nerves is advised after hernia repair and leads to a decrease in chronic pain and improved quality of life. The same approach may be considered during kidney transplantation although it is unclear whether the same positive effects are obtained. This study intends to increase awareness among kidney transplantation surgeons in order to properly inform kidney recipient, especially obese patients, about the risk of chronic pain and consider appropriate measures.