when patients with spinal cord injuries have pain as an accessory symptom , training in the 
 activities of daily living ( adl ) is affected and sometimes does not progress smoothly1 . transcranial magnetic stimulation ( tms ) 
 pulses have been used as a noninvasive and painless means of stimulating the brains of 
 intact conscious human subjects through the scalp2 . tms pulses were first used in patients with spinal cord injury 
 ( sci ) in the early 19903 and are now used 
 most extensively in the corticospinal system because the output of the primary motor cortex 
 can be easily assessed in the form of motor - evoked potentials ( meps ) using surface 
 electromyographic recording electrodes . rtms can be applied as continuous trains of low 
 frequency ( 1  hz ) or as bursts of higher frequency ( 5  hz ) . generally , low - frequency rtms 
 ( stimulus rates 1  hz ) inhibits motor cortical excitability , leading to a reversible 
  virtual lesion , whereas high - frequency rtms ( 520  hz ) usually promotes an increase in 
 cortical excitability4 . belci et al.5 first tested the efficacy of rtms in 
 modulating corticospinal inhibition and improving functional recovery in four patients with 
 chronic incomplete ( american spinal injury association impairment scale d ) cervical ( c5 
 level ) sci . perceptual thresholds for electrical stimulation of the skin , asia clinical 
 measures of motor and sensory functions , and times to complete a pegboard were found to 
 improve during the entire 3-week follow - up period . the activation of motor nerves due to 
 repetitive movements induces plastic changes in the primary somatosensory cortex6 which indicates that sensory and motor 
 nerves are directly related with each other . although it is relatively well known that 
 sensory nerves directly affect motor nerves , it has not been established whether motor 
 nerves affect sensory nerves . in this study , we hypothesized that high - frequency rtms can 
 improve sensory recovery of the lower extremities in sci patients . patients were recruited from the neurological physical therapy outpatient clinic of the 
 faculty of physical therapy , eulji university , after they agreed to participate in the 
 study . the research ethics committee of eulji university hospital approved the study , and 
 all participants provided informed , written consent prior to enrollment . all patients had 
 been diagnosed with sci , which was confirmed by computed tomography or magnetic resonance 
 imaging . patients that met the following criteria were enrolled : ( 1 ) incomplete sci ( ais c 
 or d ) by trauma ( traffic accident or fall ) , ( 2 ) cervical or thoracic sci , and ( 3 ) time 
 elapsed since sci of < 6 months . after 
 completing initial assessments , the subjects were randomly assigned to an experimental group 
 ( n=10 ) or a control group ( n=10 ) . for randomization , 
 sealed envelopes were prepared in advance and marked inside with a or b , indicating the 
 experimental or control group , respectively . subjects in the experimental group received 
 rtms and conventional rehabilitation therapy for a total of 50  min ( rtms , 20  min ; 
 conventional rehabilitation therapy , 30  min ) per day , with a 10  min rest period halfway 
 through the session . a magstim rapid2 ( magstim co. , ltd . , wales , uk ) and a figure - of - eight 
 coil with a diameter of 80  mm were used to administer rtms . in each patient , 1  hz rtms was 
 applied to the hemispheric hotspot in 10 second trains , with 50 second intervals between 
 trains . subjects in the experimental group received training five days per week for 6 weeks . conventional rehabilitation therapy consisted of neurodevelopmental facilitation techniques 
 and was administered by therapists unaware of the study protocol or group assignments . the 
 objectives of sci rehabilitation were to improve functional abilities , such as , transfer , 
 ambulation , and balance , so as to help patients achieve earlier and/or greater independence . subjects in the control group received sham rtms therapy and conventional rehabilitation 
 therapy for a total of 50  min ( sham rtms , 20  min , conventional rehabilitation therapy , 
 30  min ) per day 5days / week for 6 weeks ; the subjects in both groups received therapy on the 
 sameday . an electromyography / evoked potential system ( medelec , oxford instruments , abingdon , 
 oxfordshire , uk ) was used for the sensory nerve conduction study ( sncs ) ; stimuli were 
 applied at a position 10  cm above the lateral malleolus , and sncs was conducted at the sural 
 nerve in the lateral malleolus region . stimuli were administered at 2  hz to 10 khz and an 
 intensity of 10 to 20 ma , and the time was 0.5 sec7 . intragroup comparisons of variables before and after training were 
 made using the paired t test , whereas intergroup comparisons were performed using the 
 independent t - test . ( ibm , armonk , ny , usa ) was used for 
 statistical analysis , and p values of < 0.05 were considered significant . a summary of the clinical and demographic features of the sample ( n=20 ) is provided in 
 table 1table 1.general and medical characteristics of the subjects ( n=20)eg ( n=10)cg ( n=10)gender ( male / female)6/47/3age ( years)41.0  8.143.3  9.6time since injury ( months)3.8  1.63.7  1.1ais ( c / d)3/75/5cause ( f / ta)4/64/6eg : active rtms and conventional physical therapy group ; cg : sham rtms and 
 conventional physical therapy group ; ais : american spinal cord injury association 
 impairment scale ; f : fall ; ta : traffic accident . a significant difference was observed between group post - test velocity 
 results ( p<0.05 ) , and significant differences were found between pre- and post - test 
 results for all variables ( p<0.05 ) . the effect sizes of gains in the experimental and 
 control groups were very high for the sensory nerve conduction velocity ( effect size 1.00 
 for both ) ( table 2table 2.comparison of changes in characteristics of the experimental group and control 
 group with values presented as mean ( standard deviation)eg ( n=10)cg ( n=10)amplitude ( v)pre31.1  14.230.4  15.2post35.0  15.932.2  15.5latency(ms)pre3.6  1.03.6  0.7post3.2  0.73.3  0.4sncv(m / s)pre43.3  7.643.7  10.7post49.1  4.445.6 eg : active rtms and 
 conventional physical therapy group ; cg : sham rtms and conventional physical therapy 
 group ; sncv : sensory nerve conduction velocity ) . eg : active rtms and conventional physical therapy group ; cg : sham rtms and 
 conventional physical therapy group ; ais : american spinal cord injury association 
 impairment scale ; f : fall ; ta : traffic accident values are shown as the mean  sd . * significant difference from the pre - intervention 
 value ( p<0.05 ) . * * significantly difference from the pre - intervention value 
 ( p<0.01 ) . eg : active rtms and 
 conventional physical therapy group ; cg : sham rtms and conventional physical therapy 
 group ; sncv : sensory nerve conduction velocity high - frequency rtms is known to have control effects on motor and sensory functions8 and the fact that high - frequency rtms 
 increases primary motor cortex excitability has been well established . summers et al.9 reported when high - frequency rtms was 
 applied to the primary motor cortex , sensory and pain threshold values increased in normal 
 adults and in patients with central or peripheral nerve damage . however , the mechanism 
 responsible for sensory nerve network reactions induced by stimulating the motor cortex has 
 not been clearly identified . repeated administration of rtms pulses can induce long - lasting 
 changes in the excitabilities of the corticospinal tract , m1 , and spinal cord structures and 
 result in significant improvements in aspects of sensory and motor functions in patients 
 with motor disorde10 . the present study 
 was conducted to investigate the effect of active rtms on sensory recovery of the lower 
 extremities in patients with subacute sci . according to our results , the sncv was more 
 enhanced after the intervention in the experimental group than in the control group . furthermore , active rtms was found to be more effective at improving sensory recovery than 
 sham treatment . rtms could reduce corticospinal inhibition and thus induce motor 
 improvements in sci , and it is possible that motor score improvements induced by rtms in sci 
 could be due to enhancement of descending corticospinal projections and reductions in 
 corticospinal inhibition7 . notably , caria 
 et al.11 reported a direct relation 
 between motor and sensory nerves . ragert et al.12 reported that 5  hz rtms induced sustained increases of 
 somatosensory cortex excitability , and pleger et al.13 found that rtms of the somatosensory cortex improved tactile 
 discrimination and enhanced somatosensory cortex activation and that changes in primary 
 motor cortex were negatively correlated with gains in discrimination ability . these results 
 support the notion that rtms augments sensory recovery in subacute -stage patients when they 
 are treated within 6 months of sci14 , 15 . first , the small sample size may have adversely influenced the analysis and impacted our 
 results , and thus , our findings can not be generalized to all sci patients . second , the 
 absence of follow - up after the end of the active rtms prevented determination of the 
 durability of the effects of this intervention . further studies , including a long - term 
 follow - up assessment , are needed to evaluate the long - term benefits of rtms .