shoulder pain in hemiplegic patients has high correlations with spasticity , sensory 
 changes , and severe subluxation of the shoulder1 .
increased muscle 
 tone causes shoulder pain caused by traction of the tendon , which is a muscle - adhered region 
 resulting from the shortening and spasticity of the periarticular soft tissues2 . in previous studies , investigations of the characteristics of the tendon with diagnostic 
 ultrasonography
have generally evaluated subject age and disuse , motor , and mechanical 
 characteristics of tendons under maximum muscle contraction3 , 4 .
recent studies have also 
 found that the thickness , length , biomechanical characteristics , stiffness , and hysteresis 
 of the affected tendon were increased compared with those of the unaffected tendon in stroke 
 patients5 .
fixed positions caused by 
 immobilization of the soft tissues around the muscles and joints can lead to permanent 
 structural changes , such as decreased range of motion and stiffness6 .
the findings of previous studies7,8,9,10 suggested that shoulder dysfunctions in 
 hemiplegic patients are caused by complex factors , including spasticity , capsulitis , and 
 tendinitis .
these studies also showed that management of spasticity is critical for 
 improvement of function .
therefore , stretching and joint stabilization exercises are an 
 important therapeutic approach for improving shoulder function .
this study was conducted 
 with the expectation that this approach would decrease the muscle tone as a result of the 
 change in length of the spastic muscle , improve the activity of the antagonistic muscle , and 
 improve the activity of the tendon .
the 
 experimental protocol was approved based on the ethical standards of the declaration of 
 helsinki .
the subjects of this study were selected from patients who had been diagnosed with 
 poststroke hemiplegia and hospitalized in a hospital specializing in rehabilitation . 

the 
 inclusion criteria were as follows : patients who were six months or more but less than two 
 years after the onset of stroke , patients in which spasticity of biceps brachii was in 
 stages 13 on the modified ashworth scale ( mas ) , and patients who had no shoulder pain six 
 months before onset .
the exclusion criteria were as follows : patients who had a severe 
 injury of the rotator cuff , patients who had undergone shoulder surgery after a shoulder 
 injury , and patients considered unable to participate in this study because of psychiatric 
 problems .
this study was conducted by applying eight weeks of exercise therapy to the participants , 
 who were selected based on the above criteria .
the medical records and physical function test sheets of all hospitalized patients were 
 examined to select subjects who satisfied the criteria for this study .
the 45 patients that 
 consented to participate in this study were randomized into three groups .
one discharged 
 patient left the normal development therapy group , two discharged patients left the 
 stretching exercise therapy group , and one discharged patient left the stretching and joint 
 stabilization exercise therapy group .
consequently , 41 patients participated throughout this 
 study , and the data analysis was performed using the data of these 41 patients .
every subject received normal development therapy , for improvement of physical functions , 
 one hour and 30  min of exercise therapy three times a week , and one hour of occupational 
 therapy five times a week , in addition to the 30-min exercise therapy programs used in this 
 study . in the preliminary investigation of these exercise therapy groups ,
sonography was conducted 
 to measure the thickness of the biceps brachii tendons of both the affected and unaffected 
 sides and shoulder functions .
the evaluations were performed for all subjects at four weeks 
 and then at eight weeks when the exercise therapy intervention was completed .
normal development therapy , stretching exercise therapy , stretching and joint stabilization 
 exercise therapy , and evaluations were performed by physical therapists with at least three 
 years of clinical experience .
the authors of this paper directed and supervised the 
 consistency of the therapy programs and their evaluations . concerning the neurophysiology approach , the normal development therapy program applied in 
 this study was neurodevelopment treatment according to motor development theory and motor 
 learning theory11 .
the stretching program applied here was a revised version of that used in a previous 
 study12 .
first , maximum shoulder 
 external rotation at 45 abduction was performed in the supine position and gradually 
 extended as long as there was no pain .
then , stretching was performed at 90 of the shoulder 
 in a sitting position and gradually extended as long as there was no pain . finally , the 
 subjects reached toward the ground with their palms with shoulder and elbow extension in a 
 sitting position and gradually extended their reach as long as there was no pain .
joint stabilization exercise used in a previous study was revised13 to affect the stability and mobility of the rotator cuff , 
 scapula , and glenohumeral joint , which are involved in stabilization of the shoulder joint . 

furthermore , an elastic band was used for resistance to prevent pain and fatigue , the 
 assistance of the therapist was minimized , and a 10-second hold time was used for each 
 position . for the joint stabilization exercise ,
the subjects started in a shoulder neutral 
 position , holding the band , with shoulder abduction of 060 on the scapular plane and elbow 
 flexion of 90. next , they punched forward from the shoulder neutral position with shoulder 
 flexion of 060 on the sagittal plane and elbow flexion of 90. they then performed 
 adduction of the scapulas with elbow flexion of 90 and the shoulders in neutral rotation 
 with their arms by their sides . finally ,
they performed shoulder external rotation with 
 upper limb abduction of 45 , elbow flexion of 90 , internal rotation of 30 , and external 
 rotation of 30. the thicknesses of the long head tendons of the biceps brachii on the affected and 
 unaffected sides were measured by one physiatrist using diagnostic ultrasonography equipment 
 ( logiq 400cl , ge healthcare , wauwatosa , wi , usa ) . for sonographic measurement , the 
 cross - sectional image of the biceps groove was obtained in pronation of the forearm at 0 
 with elbow flexion of 90 , and the thicknesses were measured at the origins of the affected 
 tendons14 . for the normal tendons , thin 
 fiber aggregates were arranged in parallel , and cutting or deformation of their shape was 
 considered an abnormality15 .
the 
 thickness of the long head tendons of the biceps brachii with scar tissue was 8  mm or 
 greater , which is considered a symptom of tendinitis16 .
the measurement of functional movement of the shoulder joint used the motor assessment 
 scale for stroke , which was used in a previous study17 .
the scores ranged from 0 to 6 ; the closer to the score was to 6 , the 
 closer the function was to a normal state .
the 
 demographic characteristics of the subjects were analyzed by the independent t - test and 
 chi - squared test .
the kolmogorov - smirnov test was used to test the normality of the 
 variables .
the changes over time were compared among the three groups before the experiment 
 and at four and eight weeks after the experiment .
the differences in the changes among the 
 three groups before the experiment , at four weeks , and at eight weeks were analyzed through 
 repeated measures anova .
the bonferroni method was used to determine differences between 
 prior to the experiment and at four weeks , between four and eight weeks , and between prior 
 to the experiment and at eight weeks .
the differences in changes by period between the 
 exercise therapy groups were analyzed by ancova , and the preliminary measurements were used 
 as covariate values .
the general characteristics of the subjects and the results of homogeneity testing are 
 shown in table 1table 1 .
general characteristics of the subjects ( n=41)group variablegroup 1 ( n=14)group 2 ( n=13)group 3 ( n=14)age ( years)58.87.457.88.158.76.6height ( cm)164.57.5165.97.5165.57.8weight ( kg)60.810.562.310.762.711.4onset ( months)11.713.6211.543.0711.363.05spasticity ( grade)2.210.322.260.382.210.54*p<0.05 . the thicknesses of the affected tendons are shown in table 2table 2 .
comparison of aus between the three groups ( n=41)group variable1 ( n=14)2 ( n=13)3 ( n=14)meansdmeansdmeansdaus ( mm)0 week7.610.707.570.857.380.874 weeks7.280.577.290.847.080.748 weeks5.190.925.480.495.630.57change2.420.222.090.362.750.30*****p<0.05 ; aus : affected side ultrasonography of the biceps brachii long head 
 tendon ; change from 0 week to 8 weeks .. in the case of the normal development therapy ( group 1 ) , the thickness of the 
 affected tendon was 7.61  0.7  mm before the experiment , 7.28  0.57  mm at four weeks , and 
 5.19  0.92  mm at 8 weeks . in the repeated measurements ,
the thickness of the affected 
 tendon showed a significant decrease over time ( p<0.05 ) . in the case of the stretching 
 exercise therapy ( group 2 ) , the thickness of the affected tendon was 7.57  0.85  mm before 
 the experiment , 7.29  0.84  mm at four weeks , and 5.48  0.49  mm at eight weeks . in the 
 repeated measurements ,
the thickness of the affected tendon showed a significant decrease 
 over time ( p<0.05 ) . in the case of the stretching and joint stabilization exercise 
 therapy ( group 3 ) ,
the thickness of the affected tendon was 7.38  0.87  mm before the 
 experiment , 7.08  0.74  mm at four weeks , and 5.63  0.57  mm at eight weeks . in the repeated 
 measurements ,
the thickness of the affected tendon showed a significant decrease over time 
 ( p<0.05 ) .
* p<0.05 ; aus : affected side ultrasonography of the biceps brachii long head 
 tendon ; change from 0 week to 8 weeks .
the post - hoc comparison results were week 0:week 4 ( p<0.05 ) , week 0week 8 ( p<0.05 ) , 
 and week 4week 8 ( p<0.05 ) for all three groups , and the thickness of the affected tendon 
 significantly decreased in week 0week 4 , week 0week 8 , and week 4week 8 . the results of 
 comparison of the changes in thickness among the three groups showed no significant 
 difference between group 1 and group 2 ( p=0.84 ) .
there was a significantly greater decrease 
 in thickness in group 3 compared with group 1 ( p<0.05 ) , and there was a significantly 
 greater decrease in thickness in group 3 compared with group 2 ( p<0.05 ) .
comparison of motor assessment scale between the three groups ( n=41)group variable1 ( n=14)2 ( n=13)3 ( n=14)mean  sdmean  sdmean  sdmas ( score)0 weeks1.64  0.631.54  0.661.50  0.514 weeks2.07  0.612.08  0.492.00  0.558 weeks2.50  0.512.85  0.553.36  0.84change0.86  0.121.31
 0.111.86  0.33*****p<0.05 ; mas : motor assessment scale ; change from 0 weeks to 8 weeks .. in the case of the normal development therapy ( group 1 ) , motor function of 
 the arm was scored as 1.64  0.63 before the experiment , 2.07  0.61 at four weeks , and 2.50 
  0.51 at 8 weeks . in the repeated measurements , motor function of the arm showed a 
 significant increase over time ( p<0.05 ) . in the case of the stretching exercise therapy 
 ( group 2 ) , motor function of the arm was scored as 1.54  0.66 before the experiment , 2.08  
 0.49 at four weeks , and 2.85  0.55 at eight weeks . in the repeated measurements ,
motor 
 function of the arm showed a significant increase over time ( p<0.05 ) . in the case of the 
 stretching and joint stabilization exercise therapy ( group 3 ) ,
motor function of the arm was 
 scored as 1.50  0.51 before the experiment , 2.00  0.55 at four weeks , and 3.36  0.84 at 
 eight weeks . in the repeated measurements ,
motor function of the arm showed a significant 
 increase over time ( p<0.05 ) * p<0.05 ; mas : motor assessment scale ; change from 0 weeks to 8 weeks .
the post - hoc comparison results were week 0week 4 ( p<0.05 ) , week 0week 8 ( p<0.05 ) , 
 and week 4week 8 ( p<0.05 ) for all three groups , and the motor function of arm 
 significantly increased in week 0week 4 , week 0week 8 , and week 4week 8 .
the results of 
 the comparison of changes in function of the arm among the three groups showed no 
 significant difference between group 1 and group 2 ( p=0.151 ) .
there was a significantly 
 greater increase in function of the arm in group 3 compared with group 1 ( p<0.05 ) , and 
 there was a significantly greater increase in function of the arm in group 3 compared with 
 group 2 ( p<0.05 ) .
stretching and joint stabilization exercise therapy was applied to the spastic shoulder 
 joint to investigate changes in spastic muscle length , improvement in the coordination of 
 shoulder muscles , and tendon thickness .
the aim of the study was to demonstrate that 
 stretching and joint stabilization exercise therapy could be an important therapeutic 
 approach for the improvement of shoulder function in hemiplegic patients .
it was previously reported that the degraded function of the upper limb in hemiplegic 
 patients had significant correlations with the decrease in proprioceptors , contracture of 
 muscles , subluxation of the shoulder , increase in shoulder pain , and peripheral tissues 
 ( about 85% ) of the shoulder joint that showed lesions under ultrasonography14 .
many previous studies have evaluated lesions of the shoulder joint in hemiplegic patients 
 by ultrasonography .
ultrasonographic evaluation of the shoulder joints in poststroke 
 hemiplegic patients revealed lesions in the peripheral tissues of shoulder joints in 48 of 
 64 patients ( 75% ) .
similar lesions were found in the long head tendon of the biceps brachii 
 ( 64.8% ) and in the supraspinatus tendon18 .
an ultrasonographic evaluation of lesions for 84 hemiplegic patients 
 showed that 62.2% of the patients had lesions in the affected tendon , and the most frequent 
 lesions were tendinitis of the long head tendon of the biceps brachii and tendinitis of the 
 supraspinatus19 . in the present study , ultrasonographic evaluation of the shoulder joints in poststroke 

the 
 thickness of the affected tendon was 36% greater than that on the unaffected side , which was 
 caused by the formation of scar tissue .
this finding aligns with a previous study showing 
 that exercises and activities were important for reinforcement of the motility of shoulder 
 muscles and increase of muscle length14 . 
 in another study on spasticity accompanied by shoulder pain ,
however , application of 
 exercise consisting of passive joint stretching further increased the contracture of the 
 shoulder joint and shoulder pain because of the reflective position and protection against 
 muscle spasm .
accurate application and special care were required in the stretching 
 exercise20 . as shown by many previous studies ,
the spasticity of muscles after hemiplegia changes the 
 characteristics of muscle fibers , causes dysfunction of joint movement , and aggravates the 
 actions caused by neurologic injuries21 .
studies on shoulder dysfunction in hemiplegic patients have emphasized the importance of an 
 exercise program for shoulder stability22 , 23 .
the increase in stability and the 
 decrease in spasticity of shoulder dysfunction are considered important because of their 
 effects on stabilization of the shoulder joint .
scapula stabilization of the shoulder joint 
 and muscle strengthening exercises for the scapulohumeral external rotation muscle over six 
 weeks in patients improved scapulohumeral rhythm24 .
a previous study on stretching reported that 30  min of static 
 stretching of immobilized and shortened muscles of mice improved the mobility of 
 sarcomeres25 .
application of 30  min of 
 static stretching per day for four weeks by hemiplegic patients significantly prevented 
 contracture of joints12 .
a similar study 
 claimed that at least 30  min of stretching was required to prevent contracture of joints and 
 muscles in hemiplegic patients26 .
although previous studies found differences regarding stretching application time , they 
 commonly stressed the importance of stretching for the prevention of joint contracture and 
 the recovery of shoulder joint function in hemiplegic patients .
in particular , periarticular 
 muscle strengthening exercise is needed to improve shoulder joint function in hemiplegic 
 patients because the humerus head and scapula movements can not resist gravity , generate 
 incorrect mechanisms , and cause injuries of the periarticular soft tissue , neurologic pain , 
 and dysfunction27 .
the results of this study showed that the combined exercise therapy program of stretching 
 and joint stabilization exercises for spastic shoulder joint dysfunction in poststroke 
 hemiplegic patients reversed the pathological changes in tendons and improved shoulder 
 function .
there are many causes of shoulder dysfunction in poststroke hemiplegic patients and many 
 therapeutic approaches to them , but stretching and joint stabilization exercises are 
 indispensable to an exercise therapy program .
the results of this study could provide 
 reference data about exercise therapy intervention . extending previous studies of other 
 causes of shoulder dysfunction
, future studies will develop the results of this study in a 
 clinical setting .
   [ purpose ] this study investigated the effects of stretching and joint stabilization 
 exercises applied to spastic shoulder joints on improving shoulder dysfunction in 
 hemiplegic patients . [ subjects and methods ] hemiplegic patients were classified into three 
 groups : one group received 30  min of traditional exercise therapy for the spastic shoulder 
 joint ; one group received 30  min stretching ; and one group received 15  min of stretching 
 and 15  min of joint stabilization exercises . 
 the exercises were performed once a day , five 
 times per week for eight weeks . 
 changes in the pathologic thickness of tendons and 
 recovery of shoulder function were compared among the three groups . 
 differences among the 
 three groups before the experiment , at four weeks , and at eight weeks were analyzed using 
 repeated measures anova . 
 [ results ] the stretching and joint stabilization exercise therapy 
 group showed greater improvement in shoulder function than the traditional exercise 
 therapy group and the stretching only group . 
 this group also showed greater decreases in 
 the pathologic thickness of tendons , than the other groups . 
 [ conclusion ] this study 
 demonstrated that an exercise therapy program that combined stretching and joint 
 stabilization exercise was more effective than other exercises for improvement of spastic 
 shoulder joint dysfunction in hemiplegic patients . 
INTRODUCTION
SUBJECTS AND METHODS
RESULTS
DISCUSSION