Minimally Invasive versus Classic Procedures in Total Hip Arthroplasty: A Double-blind Randomized Controlled Trial Minimally invasive total hip arthroplasty--our clinical experience. Minimal-invasive posterior approach for total hip arthroplasty versus standard lateral approach. Randomized control trial comparing radiographic total knee arthroplasty implant placement using computer navigation versus conventional technique. [Clinical outcome following robotic assisted versus conventional total hip arthroplasty: a controlled and prospective study of seventy-one patients]. Minimally invasive total hip arthroplasty: a randomized controlled prospective trial A randomized, prospective study of 3 minimally invasive surgical approaches in total hip arthroplasty: comprehensive gait analysis. Comparison of gait in patients following a computer-navigated minimally invasive anterior approach and a conventional posterolateral approach for total hip arthroplasty: a randomized controlled trial. New two-incision minimally invasive total hip arthroplasty: comparison with the one-incision method Robot‐assisted total hip arthroplasty: Clinical outcomes and complication rate Total hip arthroplasty through a minimally invasive lateral approach--our experience and early results. Antero-lateral minimal invasive (ALMI) approach for total hip arthroplasty technique and early results [Advantages of minimal invasive total hip replacement in the early phase of rehabilitation]. Comparative study between computer assisted-navigation and conventional technique in minimally invasive surgery total knee arthroplasty, prospective control study. [Minimally invasive posterior approach for total hip arthroplasty]. Enhanced early outcomes with the anterior supine intermuscular approach in primary total hip arthroplasty. Mini-incision versus mini-incision and computer-assisted surgery in total knee replacement: a radiological prospective randomised study.
Background For total hip arthroplasty ( THA ) , minimally invasive surgery ( MIS ) uses a smaller incision and less muscle dissection than the classic approach ( CLASS ) , and may lead to faster rehabilitation . Questions / purpose sDoes minimally invasive hip arthroplasty result in superior clinical outcomes ? Patients and Methods In this double-blind r and omized controlled trial , 120 consecutive primary noncemented THAs in 120 patients were assigned to one of two groups ( MIS or CLASS ) . The r and omization sequence was stratified for two groups of surgeons , ie , those using a posterolateral approach ( PL-CLASS or PL-MIS ) and those using an anterolateral approach ( AL-CLASS or AL-MIS ) . Length of the incisions was 18 cm for the CLASS procedures . MIS incisions were extended at the skin level to 18 cm at the end of the procedure . The primary end point was the Harris hip score ( HHS ) at 6 weeks postoperatively . Patient-centered question naires were obtained preoperatively and after 6 weeks and 1 year . Results For the patients in the MIS group ( average 7.8 cm incision length ) , statistically significant increased mean HHSs were seen compared with the CLASS group at 6 weeks and 1 year . This difference was small and mainly caused by the favorable results of the PL-MIS . In the MIS group , surgical time was longer . A learning curve was observed based on operation time and complication rate . Although not statistically significant , the perioperative complication rate was rather high in the ( anterolateral ) MIS group . Conclusions The minimal invasive approach in THA did not show a clinical ly relevant superior outcome in the first postoperative year . Level of Evidence Level I , therapeutic study . See Guidelines for Authors for a complete description of levels of evidence BACKGROUND Minimally invasive prosthetic hip surgery ( MIS ) attempts to minimise the extent of the operation . The aim of the study was to describe minimally invasive hip surgery and to present early clinical experience of the authors . MATERIAL AND METHODS 41 minimally invasive hip replacements through a posterior approach were carried out at the Orthopaedic Department of the Postgraduate Medical Education Centre in Otwock between 2004 and 2006 . 29 of those patients were included into the study , of whom 23 presented for follow-up . A control group consisted of 29 r and omly selected patients operated on using the classical method . Patients qualified for MIS had a BMI below 30 and a structurally normal hip joint with a good range of motion .  RESULTS Early results were subjected to a statistical analysis of 20 parameters . CONCLUSION 1 . The analysis showed that statistically significant baseline differences between MIS and traditionally treated patients included only BMI scores , structure of the hip joint and range of motion . 2 . Implantation of a hip endoprosthesis in a MIS procedure does not differ from the traditional operation utilising a posterior access except for skin incision length In this prospect i ve study we compared clinical and radiological results and rehabilitation progress of 64 patients who underwent total hip arthroplasty using the st and ard lateral approach with 64 patients operated with a minimal-invasive ( MIS ) posterior approach .  The outcome of our study did not show any significant differences with regard to patient 's safety such as complication rate and radiological assessment of the cup position . There was no difference in the duration of surgery , blood loss , hospital stay and postoperative leg length discrepancy . Rehabilitation milestones were achieved earlier by MIS patients and three and six months postoperatively , the Harris Hip Score of the MIS group was significantly higher The aim of this study is to assess the radiological outcome of conventional techniques versus computer-navigated surgery for total knee arthroplasty . Ninety patients with knee arthritis were prospect ively r and omized into 3 groups : conventional technique : extramedullary ( EM ) and intramedullary ( IM ) tibia guide versus computer navigation surgery ( CAS ) . Two surgeons performed all procedures . St and ardized long leg coronal and sagittal x-rays were evaluated by a blinded assessor . Our results showed that CAS had greater consistency and accuracy in implant placement . In the coronal view , 93.3 % in the CAS group had better outcomes compared with EM ( 73.4 % ) and IM ( 60.0 % ) . In the sagittal axis , 90.0 % CAS also had better outcomes compared with EM ( 63.3 % ) and IM ( 76.7 % ) . Computer-navigated total knee arthroplasty helps increase accuracy and reduce " outliers " for implant placement AIM Robotic assisted total hip arthroplasty  remains controversial , since wider exposure of the proximal femur and placement of the leg in maximal hip adduction and external rotation using a rigid leg-holder apparatus may impair significantly the hip abductors . Consequently , it is the purpose of this study to analyse and report both clinical outcome and hip abductor function following robotic assisted versus conventional total hip arthroplasty . MATERIAL AND METHODS 36 robotic-assisted ( CASPAR , Orto-Maquet , Rastatt , Germany ) and 35 conventional cementless total hip arthroplasties  were followed on average for 18 months regarding incidence of complications , Harris hip score , the scoring system according to Merle d'Aubigné and Postel , hip abductor function ( using a spring-balance ) , and incidence of Trendelenburg 's sign ( according to the Kuhfuss-classification ) . Statistical analysis was performed in case of continuous data using the t test and the Mann-Whitney test , respectively , and in case of categorical data using Fisher 's exact test and the chi-squared test , respectively . The level of significance was set as p < 0.05 . RESULTS Average duration of surgery ( CASPAR : 100.6 min ; conventional : 51.5 min ; p < 0.0001 ) as well as average loss of haemoglobin ( CASPAR : 4.5 mg/dL ; conventional : 3.3 mg/dL ; p = 0.0002 ) differed significantly , whereas the incidence of complications ( CASPAR : two dislocations , one sciatic paresis , one deep infection ; conventional : one dislocation , two fissures ) , revision rate ( CASPAR : 5.6 % ; conventional : 2.9 % ) , and incidence of heterotopic ossifications ( CASPAR : 30.6 % ; conventional : 17.1 % ) was comparable following both procedures ( p > 0.05 ) . Improvement of the Harris hip score also was comparable in both groups ( CASPAR : 40.9 to 86.1 points ; conventional : 39.5 to 88.0 points ; p = 0.21 ) , whereas improvement of the score according to Merle d'Aubigné and Postel was significantly greater following the manual procedure ( CASPAR : 10.1 to 16.0 points ; conventional : 8.3 to 16.6 points ; p < 0.0001 ) . Differences between the two groups were also significant regarding hip abductor function ( CASPAR : 76.1 % ; conventional : 93.8 % of the contralateral hip ; p < 0.0001 ) and incidence of Trendelenburg 's sign ( CASPAR : 61.1 % ; conventional : 25.7 % ; p = 0.0014 ) . CONCLUSION The significant functional impairment following robotic assisted THA should be taken critically into consideration prior to initiating such procedure Introduction Advantages of minimally invasive total hip arthroplasty ( THA )  are controversially discussed . Method In this prospect i ve study 51 patients ( 52 hips ) were r and omly allocated to a classical lateral or a minimally invasive approach ( modification of the Hardinge-approach ) . Operating time , intraoperative blood loss , postoperative hemoglobin , muscle enzymes CK and myoglobin were recorded . Radiologically the positioning of the prosthesis was analyzed . WOMAC- and Harris Hip Score ( HHS ) were assessed preoperatively , at discharge , at 6 weeks and 3 months . Results In the minimally invasive group there was a shorter length of surgery , the scores in the WOMAC and HHS were slightly better at discharge and at the 3 months- examination , myoglobin-rise was slightly less . The positioning of the prosthesis was good in both groups . Minimally invasive THA led to a quicker recovery , at 3 months postoperative there was still a slight difference to the st and ard group . Conclusion If these slight differences subside has to be examined in studies with a longer follow-up Purported advantages of total hip arthroplasty performed with minimally invasive surgical ( MIS ) approaches are less muscle damage and faster recovery . There are little data scientifically evaluating these cl aims . Twenty-four consecutive hips were r and omized to total hip arthroplasty through 1 of 3 MIS approaches ( 2-incision , mini-posterior , and mini-anterolateral ) . Each patient underwent preoperative and postoperative gait analysis . Gait parameters included vertical ground reaction force , velocity , single-leg stance time , limb-loading rate , and abductor torque . All 3 groups demonstrated overall improvements in gait parameters at 6 weeks postoperatively . The anterolateral approach patients showed a decrease in the vertical ground reaction force at mid-stance , whereas the 2-incision and posterior approaches demonstrated no significant change . These results fail to demonstrate any significant advantage of the 2-incision approach over the posterior approach in kinetic gait parameters . Furthermore , the anterolateral approach demonstrates a gait pattern consistent with abductor muscle injury in the early recovery period , despite the MIS approach Minimally invasive total hip arthroplasty ( MIS THA ) aims at minimizing damage to muscles and tendons to accelerate postoperative recovery . Computer navigation allows a precise prosthesis alignment without complete visualization of the bony l and marks during MIS THA . A r and omized controlled trial ( RCT ) was conducted to determine the effectiveness of a computer-navigated MIS anterior approach for THA compared to a conventional posterolateral THA technique on the restoration of physical functioning during recovery following surgery . Thirty-five patients underwent computer-navigated MIS THA via the anterior approach , and 40 patients underwent conventional THA using the conventional posterolateral approach .  Gait analysis was performed preoperatively , 6 weeks , and 3 and 6 months postoperatively using a body-fixed-sensor based gait analysis system . Walking speed , step length , cadence , and frontal plane angular movements of the pelvis and thorax were assessed . The same data were obtained from 30 healthy subjects . No differences were found in the recovery of spatiotemporal parameters or in angular movements of the pelvis and thorax following the computer-navigated MIS anterior approach or the conventional posterolateral approach . Although gait improved after surgery , small differences in several spatiotemporal parameters and angular movements of the trunk remained at 6 months postoperatively between both patient groups and healthy subjects Background There has been increasing interest in performing total hip arthroplasty ( THA ) with minimally invasive surgery ( MIS ) . This study was conducted to examine the effectiveness of MIS-THA using the new two-incision technique versus the one-incision technique . Methods A consecutive series of 113 patients who underwent MIS-THAs ( 63 one-incision cases , 50 two-incision cases ) were studied .  One-incision THA was performed with a posterolateral approach . For the two-incision , the first incision for cup insertion was made over the anterolateral side of the hip . Intermuscular dissection was performed between the gluteus medius and the tensor fascia lata . The second incision , for stem insertion , was made on the posterolateral side of the hip along the fiber of the gluteus maximus . Intermuscular dissection was made between the gluteus medius and the piriformis . Results Postoperative rehabilitation was significantly more rapid in the new two-incision group compared to the group with one incision . Postoperatively , the Harris Hip Score and the Western Ontario and the McMaster Universities Osteoarthritis Index score were significantly different between the two groups , especially the functional sections . Conclusions The findings of this study show that our new two-incision MIS-THA is an excellent surgical modality that allows early rehabilitation BACKGROUND The purpose of this study was to report minimum 2-year outcomes and complications for robotic-arm-assisted total hip arthroplasty ( THA )  . METHODS Data were prospect ively collected and retrospectively review ed between June 2011 and April 2014 . Inclusion criteria were primary robotic-arm-assisted THAs treating idiopathic osteoarthritis with ≥ 2-year follow-up .  Demographics , operating time , complications , 2-year outcome scores and satisfaction , and subsequent surgeries were recorded . RESULTS There were 181 cases eligible for inclusion , of which 162 ( 89.5 % ) had minimum 2-year follow-up . At the latest follow-up , the mean visual analogue scale was 0.7 , satisfaction was 9.3 , Harris hip score was 91.1 and forgotten joint score was 83.1 . Six ( 3.7 % ) intraoperative complications and six ( 3.7 % ) postoperative complications were reported . No leg length discrepancies ( LLDs ) or dislocations were reported . CONCLUSIONS Robotic-arm-assisted THA demonstrates favourable short-term outcomes and does not result in a higher complication rate compared to non-robotic THA as reported by the literature BACKGROUND AIMS Evaluation of : 1 . early clinical and radiographic results of  total hip arthroplasty ( THA ) through a st and ard lateral direct approach , 2 . early clinical and radiographic results of THA through a minimal lateral approach , 3 . comparison of the results of THA in these two groups . MATERIAL AND METHODS 120 THAs ( 60 cementless and 60 cemented ) done in 120 patients due to degenerative changes were evaluated prospect ively . 60 THAs were done through a minimal lateral approach and constituted a study group . 60 THAs were done through a direct lateral approach and constituted a control group . The mean age of the 120 patients ( 98 women and 22 men ) was 45 y.o . ( range : 32 - 67 y.o . ) . The duration of follow-up in the study group was from 6 to 12 months ( mean : 8.5 months ) . The duration of follow-up in the control group was from 10 to 16 months ( mean : 10.5 months ) . Mean preoperative functional status of the study group was 44.5 points according to the Harris hip score . Radiographic evaluation of the results was done according to the criteria of the Joint Committee of the Hip Society , AAOS and SICOT . RESULTS 6 months after THA , clinical results were 92 pts in the study group and 88 pts in the control group . Radiographic outcomes were very good in all 120 patients from both arms : there were no differences between the control and study group . The incidence of complications was similar in both groups . CONCLUSIONS Minimally invasive THA demonstrated its value in the treatment of  degenerative changes of the hip joint  with regard to short-term outcomes . The clinical and radiographic outcomes were comparable between the st and ard and minimally invasive approaches . Success with THA using a minimally invasive approach depends on excellent operative technique and experience with st and ard hip approaches rather than on the use of special instruments Introduction : Minimally invasive surgery represents one of the most recent techniques to have emerged within THA . In conventional THA , the incision typically measures 15–20 cm . Minimal invasive approach defined as less invasive to the skin , muscles , or bone may reduce complications and improve recovery time . A number of different approaches and methods have been described in literature . Purpose : This is a prospect i ve study describing the technique and early results of the modified antero-lateral minimal invasive ( ALMI ) approach and comparing our results to the results of other investigators interested in minimal invasive THA . Material s and methods : Seventy-five consecutive primary total hip arthroplasties ( cemented and cementless ) were done through a modified ALMI approach ( 6–8 cm ) , in which we kept the hip abductors intact . Neither special instruments nor specially design ed prostheses were needed . Minimum follow-up was 12 months . Results : The mean Harris hip score for patients after 12-month follow-up was 90 while the mean Merle d’Abugine mean score was 16.5 . Both scores reached almost the maximum values within 3 months after surgery . The cup abduction angle for 70 % patients was between 35 ° and 45 ° . No femoral stem mal-alignment was recorded . The mean operative time of cemented prosthesis was 65 min while that of the cementless prosthesis was 55 min . No wound complications or dislocations were recorded . All the patients were allowed to weight bear in the second post-operative day and involved in an early rehabilitation program . Conclusion : ALMI hip approach with sparing of hip abductors is safe and gives excellent orientation for positioning of prosthesis components . It also allows early and smooth post-operative rehabilitation with fast recovery of the patient in terms of weight bearing UNLABELLED In arthroplasty the term " minimal invasive " not only refers to the length of the skin incision but more so to its soft tissue and thereby muscle-protecting features . STUDY AIM The aim of this study is to compare the early postoperative mobilisation and rehabilitation of the different surgical approaches in cementless total hip arthroplasty . METHODS 27 patients underwent a total hip replacement ( Trilogy cup , MAYO stem ) via a ventral minimal invasive approach ( one incision technique ) ( MIS group ) . 23 patients underwent a total hip replacement with the same implant via a anterolateral transgluteal approach ( st and ard group ) . We evaluated the Harris Hip Score ( HHS ) , the visual analogue scale ( VAS ) for pain and patient satisfaction preoperatively as well as 3 days , 10 days , 6 weeks and 3 months postoperatively . RESULTS After 3 and 10 days the MIS group showed better scores for pain , gait and mobilisation as well as for the overall HHS compared to the st and ard group . These differences could not be shown 6 weeks postoperatively . The MIS group had a significantly higher rate of complications with 22 % transient impairment of the lateral cutaneous nerve . CONCLUSION The patients of the MIS group showed a better mobilisation and rehabilitation during the early postoperative period . This can be attributed to the lessened intraoperative damage of to soft tissue and especially muscle damage . Due to the increased rate of nerve irritations , we modified our surgical approach . The minimal invasive approach to modern hip joint arthroplasty remains a non-st and ard technique . Compared to the st and ard approach it carries additional risks ( like nerve damage and malpositioning of the implants and thus should remain in the h and s of the experienced orthopaedic surgeon in specialised orthopaedic centres BACKGROUND Both Minimally Invasive surgery ( MIS ) and Computer-Assisted Surgery ( CAS ) are useful in Total Knee Arthroplasty ( TKA ) . Minimally invasive total knee arthroplasty was associated with decreased blood loss , shorter hospital stays , and increased range of motion .  Computer-assisted surgery in total knee arthroplasty was developed to improve the positioning of implants during surgery . OBJECTIVE To evaluate radiographic results relative to component position and limb alignment when using a navigation system compared with conventional technique in MIS-TKA . MATERIAL AND METHOD A prospect i ve control study was performed in 180 patients who underwent total knee arthroplasty by one surgeon . All patients were r and omly divided into two groups , Conventional and Navigation TKA .  Intra- , post-operative data , and postoperative limb alignment were recorded for comparison in both groups . RESULTS The postoperative mechanical axis was within 3 degrees of neutral mechanical alignment in 94 % of the navigation group and 87 % in conventional group ( p = 0.13 ) . Registration time of navigation group is 13.58 minutes . No statistical significant difference was found in tourniquet time and postoperative blood loss in both groups . CONCLUSION The use of navigation in total knee arthroplasty increases accuracy in limb and implants alignment , and does not increase complications and surgical times The mini-posterior approach for total hip arthroplasty ( THA )  belongs to the mini-incision approaches . In comparison to st and ard approaches , less muscle trauma result ing in less pain , less blood loss and faster rehabilitation in the early postoperative period are attributed to this approach , as known for all other minimally invasive approaches . In a prospect i ve study of 100 cases of THA it could be shown that this is true when comparing the mini-posterior approach with the posterolateral approach . Lower levels of muscle enzymes as a parameter for muscle trauma , could not be seen The advantages of minimally invasive surgical approaches for total hip arthroplasty are reported to include reduced blood loss , less pain , and shorter hospital stays , which combine to afford a faster recovery1 - 4 . However , other studies have failed to show any significant advantage over the use of st and ard surgical approaches ( Fig. 1)5 - 8 . Reported disadvantages of minimally invasive techniques are the substantial learning curve required and an increased risk of early complications3,9 - 12 . In addition , the long-term outcomes of minimally invasive procedures in terms of implant fixation and longevity remain unproven . Fig. 1 The st and ard direct lateral approach to the hip previously described by Frndak et al.21 is performed with the patient in the lateral decubitus position . ( Printed with permission of Joint Implant Surgeons , Inc. ) There are three basic categories of so-called minimally invasive total hip arthroplasty approaches : an abbreviated incision ( small incision ) , modifications of st and ard approaches with smaller incisions and less soft-tissue dissection ( less invasive ) , and novel approaches that reportedly do not cut muscle ( minimally invasive ) . We have had a broad experience , over the past seven years , with a less invasive modification of the direct lateral approach ( a modified Hardinge approach ) ( Fig. 2 ) . We previously reported less blood loss and a shorter hospital stay in association with this approach13 . Others have argued that the less invasive direct lateral approach does not provide an advantage over the traditional approach5 . Importantly , the soft-tissue dissection still requires removing and repairing the abductor musculature . Fig. 2 The less invasive direct lateral approach is performed with the patient in the lateral decubitus position . This approach employs an abbreviated skin and fascial incision with a limited abductor muscle dissection13 . ( Printed with permission of Joint Implant Surgeons , Inc. ) Several recent reports have The aim of this trial was to compare the radiological results of 74 patients undergoing a mini-invasive total knee replacement ( TKR ) using either a traditional alignment guide ( MIS group ) or a computer assisted alignment system ( MICA group ) . All the patients were prospect ively r and omised to either group and the same implant was used for both groups . At 8 months post-operatively , the frontal femoral component angle ( FFC ) , the frontal tibial component angle ( FTC ) , the hip-knee-ankle angle ( HKA ) and the sagittal orientation of components ( slopes ) were evaluated respectively . The slopes of the femoral component and the FTC angle were statistically better aligned in the MICA group ( p<0.001 ) . The MICA group showed both a significant fewer number of outliners and a significant higher number of implants with all five radiological parameters ideally aligned . The operative time was statistically longer in the computer assisted group
Strong evidence was found for a decrease in operative time and intraoperative blood loss for MIS THA , with no difference in complication rates and risk for acetabular outliers .
Strong evidence exists that there is no difference in physical functioning , measured either by question naires or by gait analysis .
Moderate evidence was found for a shorter length of hospital stay after MIS THA .
Conflicting evidence was found for a positive effect of MIS THA on pain in the early postoperative period , but that effect diminished after three months postoperatively .
Strong evidence was found for an increase in operative time for CAS THA , and limited evidence was found for a decrease in intraoperative blood loss .
Furthermore , strong evidence was found for no difference in complication rates , as well as for a significantly lower risk for acetabular outliers .
Conclusions The results indicate that MIS THA is a safe surgical procedure , without increases in operative time , blood loss , operative complication rates and component malposition rates .
However , the beneficial effect of MIS THA on functional recovery has to be proven .
The results also indicate that CAS THA , though result ing in an increase in operative time , may have a positive effect on operative blood loss and operative complication rates .
More importantly , the use of CAS results in better positioning of acetabular component of the prosthesis
Background Both minimally invasive surgery ( MIS ) and computer-assisted surgery ( CAS ) for total hip arthroplasty ( THA ) have gained popularity in recent years .
We conducted a qualitative and systematic review to assess the effectiveness of MIS , CAS and computer-assisted MIS for THA .