a 20-year - old man had a history of multiple subluxation / dislocation episodes of the shoulder joint for several years and he could voluntarily dislocate his shoulder . the physical examination showed the sulcus sign ( grade 2 ) , a positive anterior drawer test ( grade 2 ) and a positive posterior drawer test ( grade 2 ) . preoperatively , the rowe score was 35 and the american shoulder and elbow surgeons ( ases)/university of california , los angeles ( ucla ) score was 80 and 25 respectively . mri of the left shoulder demonstrated a multiseptated cyst in the inferior aspect of the glenoid neck and a suspected labral tear ( arrows ) ( fig . the patient was placed in the lateral decubitus position with longitudinal traction of the affected upper limb and he was given general anesthesia . an arthroscope was inserted through a posterior portal , and the intra - articular lesions were examined . the biceps tendon and rotator cuff tendon were intact . the arthroscopic findings showed a 2  1 cm sized multilobulated cyst on the inferior labrum from 6 o'clock to 7 o'clock ( fig . 2 ) . a whitish colored cystic sac was found and then mucinous fluid was noted after piercing the sac with a spinal needle . the arthroscopic findings showed a 2  1 cm multilobulated cyst at the antero - inferior labrum from 4 o'clock to 6 o'clock , and the cyst was filled with mucinous fluid ( fig . seemingly , incomplete detachment of the inferior labrum and a marginal crack could be detected ( fig . 2b ) , but complete detachment of the postero - inferior labrum was confirmed with a probe ( fig . 2c ) . we debrided and detached the labral tear site completely and then arthroscopic anterior and posterior labroplasty was done with suture anchors ( smith & nephew , andover , ma , usa ) . three anchors were initially used and these were inserted into the postero - inferior glenoid and then the posterior labral repair was done ( fig . 3a ) two more anchors were inserted into the antero - inferior glenoid and then labroplasty was done ( fig . also , the capsular defect produced by the excisional procedure was repaired with # 2 ethibond ( fig . finally , inferior capsular plication and rotator interval closure were done with # 2.0 polydioxane sutures to augment the capsular redundancy . pendulum exercise was started on postoperative one day . during the following six weeks , passive range of motion after six weeks , we started strengthening exercise for the rotator cuff muscles and the scapular stabilizing muscles . at postoperative 2 years , physical examination showed the sulcus sign ( grade 1 + ) , an anterior drawer test of grade 1 + , a posterior drawer test of grade 1 + and a negative apprehension test . at the last follow - up , the rowe score was 85 and the ases / ucla score was 98.5 and 33 , respectively . the follow - up mri showed complete resolution of the inferior paralabral cyst ( fig . the patient was placed in the lateral decubitus position with longitudinal traction of the affected upper limb and he was given general anesthesia . an arthroscope was inserted through a posterior portal , and the intra - articular lesions were examined . the biceps tendon and rotator cuff tendon were intact . the arthroscopic findings showed a 2  1 cm sized multilobulated cyst on the inferior labrum from 6 o'clock to 7 o'clock ( fig . 2 ) . a whitish colored cystic sac was found and then mucinous fluid was noted after piercing the sac with a spinal needle . the arthroscopic findings showed a 2  1 cm multilobulated cyst at the antero - inferior labrum from 4 o'clock to 6 o'clock , and the cyst was filled with mucinous fluid ( fig . seemingly , incomplete detachment of the inferior labrum and a marginal crack could be detected ( fig . 2b ) , but complete detachment of the postero - inferior labrum was confirmed with a probe ( fig . 2c ) . we debrided and detached the labral tear site completely and then arthroscopic anterior and posterior labroplasty was done with suture anchors ( smith & nephew , andover , ma , usa ) . three anchors were initially used and these were inserted into the postero - inferior glenoid and then the posterior labral repair was done ( fig . 3a ) two more anchors were inserted into the antero - inferior glenoid and then labroplasty was done ( fig . also , the capsular defect produced by the excisional procedure was repaired with # 2 ethibond ( fig . 3c ) . finally , inferior capsular plication and rotator interval closure were done with # 2.0 polydioxane sutures to augment the capsular redundancy . pendulum exercise was started on postoperative one day . during the following six weeks , passive range of motion after six weeks , we started strengthening exercise for the rotator cuff muscles and the scapular stabilizing muscles . at postoperative 2 years , physical examination showed the sulcus sign ( grade 1 + ) , an anterior drawer test of grade 1 + , a posterior drawer test of grade 1 + and a negative apprehension test . at the last follow - up , the rowe score was 85 and the ases / ucla score was 98.5 and 33 , respectively . the follow - up mri showed complete resolution of the inferior paralabral cyst ( fig . shoulder instability is divided voluntary and involuntary instability . for the case of involuntary instability , surgical treatment is necessary , but for the case of voluntary instability , the surgical indications should be strict because of secondary compensation such as military issues and the occupational worker 's gain . if there is a pathologic condition such as labral tear , cyst and/or rotator cuff injury , then surgical treatment should be considered . a paralabral cyst of the shoulder joint can be observed in 2% to 4% of the general population , and particularly in men during the third and fourth decades . on average , these cysts measure 10 mm to 20 mm in diameter and they are preferentially located on the postero - superior aspect of the glenoid.1 ) the cysts may or not be observed to communicate with a labral tear . westerheide et al.2 ) and westerheide and karzel3 ) advocated that labral pathology was the main cause of periarticular cysts . on the contrary , piatt et al.4 ) reported that paralabral cysts spontaneously resolved in 2 patients , as assessed on mri . youm et al.5 ) reported that repair of a labral tear , without cyst excision , resulted in successful outcomes for all 10 patients who had spinoglenoid cysts associated with superior labral tears . they advocated that the treatment given for intra - articular disease was the key component of the surgical management . the symptoms of a paralabral cyst may be the result of rotator cuff disease , labral disease , entrapment syndrome from compression of the suprascapular nerve , instability or a combination of these conditions.1,4,6,7 ) the most common complication is the suprascapular nerve entrapment syndrome , which leads to pain and supraspinatus and/or infraspinatus atrophy . in the shoulder , a labral the english medical literature shows only 3 reports of the paralabral cyst of the shoulder associated with glenohumeral instability.8 - 10 ) our current report is a rare case of inferior paralabral cyst combined with multidirectional instability . the previous reports only describe anterior , posterior and superior paralabral cyst with shoulder instability . ferrick and marzo9 ) reported that suprascapular entrapment neuropathy with ganglion is related to posterior shoulder instability . dietz et al.8 ) reported that anterior - inferior labral cyst with an anterior labral tear was related with non - traumatic shoulder instability , and yukata et al.10 ) also reported that paralabral cyst of the shoulder was associated with recurrent anterior dislocation . tirman et al.11 ) reported that labral cysts may be an indicator of labrocapsular injury and instability , and so taking a careful history and a thorough physical examination to detect instability should be considered . in that report , the physical examination showed glenohumeral instability in the direction of the labral tear and a cystic - appearing mass in 11 patients ( 11/20 , 55% ) ; the instability pattern was multidirectional in three patients and unidirectional in eight patients . this cyst was just nearby the axillary nerve , but the postoperative deltoid function was unaffected . so , we suspected that repetitive microtrauma was the main cause of the inferior labral tear and the paralabral cyst . the relationship between shoulder instability and labral tears is well known , yet the association of shoulder instability with a paralabral cyst is rare . we considered that there was the cyclic correlation of shoulder instability , labral tear and paralabral cyst . in the future shoulder instability may cause labral injury , or labral injury may cause shoulder instability , and then the injured tear labrum develops a paralabral cyst . in our patient ,
paralabral cyst of the shoulder joint can be observed in 2% to 4% of the general population , particularly in men during the third and fourth decade . on average , 
 these cysts measure 10 mm to 20 mm in diameter and are located preferentially on the postero - superior aspect of the glenoid . 
 the mri has increased the frequency of the diagnosis of paralabral cysts of the shoulder joint . 
 paralabral cysts of the shoulder joint usually develop in the proximity of the labrum . 
 the relationship between shoulder instability and labral tears is well known , however , the association of shoulder instability with a paralabral cyst is rare . 
 shoulder instability may cause labral injury or labral injury may cause shoulder instability , and then injured tear develops paralabral cyst . in our patient , the inferior paralabral cyst may be associated with inferior labral tears and instability mri .