[Purpose] Does repetitive throwing influence the glenoid version and torsion of the humeral head ?The aim of this study is to estimate the influence for the version and torsion in athletes who participate in beseball from a certain growth period.
[Material and Methods] Computerized tomographic scans were made for 64 shoulders of thirty-two baseball players with an average age 24.0 years. And 20 shoulders of ten non-baseball players, with an average age 29.0 years as the control group. On each scan, we drew four lines: a perpendicular line to a line connecting the peripheral margins of the articular surface of the humelal head (line A): a line connecting the central point of the humeral epicondyle (line B): a line drawn from the mid-point of the glenoid fossa to the medial end of the scapula (line C): and a perpendicular line to a line connecting the anterior and posterior margins of the glenoid fossa (line D). The angles between line A and B, and between line C and D were taken as torsion of the humeral head and glenoid version respectively.
[Results] The average angle of the glenoid version was -4.26° on the throwing side and -1.18° on the non-throwing side. In the control group, the average angle of the glenoid version was -0.27° on the dominant and -1.72 ° on the non-dominant side. The average angle of the retroversion was 36.02° on the thowing and 29.56° on the non-throwing side. In the control group, the average angle of the retroversion was 28.52° on the dominant and 29.66° on the non-dominant side. There was a statistically significant difference between the throwing and non-throwing sides.
[Conclusion] These results suggested that excessive and repetitive stress to the humerus during a growth period influenced the version and trorsion

View full abstract

The purpose of this study was to clear the clinical results of conservative treatment including the correct pitching form and operative treatments.51 baseball players were studied. Their average age was 22. ly. o. Conserative treatment group including the correct pitching form which in the divided into 7steps and proceeded from the wrist to the foot. Elevating the arm and keeping the scapular plane with the forearm pronated and rotating the trunk on the hip joint were most important. Almost all of the cases had contracture in flexion and adduction of the shoulder.19 cases had problems besides the shoulder and scapula.24 baseball players could play as well as before injury. But players with an injured labrum tear and a partial thickness tear of the rotator cuff could not.10 baseball players had arthoscopic treatment including repair of BLC lesions (Biceps tendon/labrum comlex). Average age was 22 y. o.7 cases had BLC lesions and 8 cases had partial thickness joint side tears. Debridment of the labrum and rotator cuff were performed and repaired BLC lesion with the ROC fastener system in 5 cases.7 cases could play as well as before and all the this cases treatment with repaired BLC recovered completely. Thus we recommend this treatment.

View full abstract

[Purpose] The purpose of this study is to analyze the influence of the scapulothoracic joint on the rotator cuff function using integrated electromyography.
[Materials and Methods] Ten shoulders of ten young males who were diagnosed as having dysfunction of scapulothoracic joint with ⌈Scapula-45⌋ radiography and resisted abduction and external rotation test. The activities of the supraspinatus, infraspinatus, deltoid, and biceps were evaluated electromyographically with the loads at 45 degrees elevated position in the scapular plane. Subsequently the activity of these muscles was collected with a manual assist to the scapulothoracic function. The EMG activity was expressed as a percentage of the Max MMT (%MMT).
[Results] The EMG activity increased with the load in all the cases. In 80% of the total cases, the relationship between the supraspinatus and deltoid did not change irrespective of the load (deltoid/supuraspinatus=1 /1.3) without manual assistance. The %MMT of the supraspinatus and deltoid of these cases showed a significant difference between the activity with and that without manual assistance. The tendency was remarkable at 3kg load. In 20% of the total cases, a dysfunction of rotator cuff was noted.
[Conclusion] The results suggest the function of scapulothoracic joint has an effect on the rotator cuff function.

View full abstract

Measurements on arthrograms were compared between the presence and the absence of laxity of theglenohumeral joint for the purpose of assessing factors for glenohumeral instability.93 shoulders under 40 years old (average 20.7) were selected as subjects. Arthrography was conducted under imaging to obtain the anterior-posterior view in internal rotation by 60 degrees in the supine position as well as the axial view in abduction by 90 degrees in the sitting position, and these views were recorded. Then, the sizes of the anterior pouch and the inferior pouch and those of the anterior ballooning and posterior ballooning were measured respectively in the anterior-posterior view and in the axial view. The subjects were divided into two groups by the presence or absence of loosenig or slipping or anterior shift, and statistical tests to determine the significant differences were conducted. The patients, whose humeral head was moved anteriorly by not less than 20% when it was pushed from backwards in the same position as in the axial view, were determined as positive for anterior shift. There was no significant difference in the presence or absence of loosening. The patients who were determined to be positive in slipping had significantly larger anterior pouches (p<0.01). The patients who were determined to be positive for anterior shift had significantly larger anterior ballooning (p<0.05). Based on these results, we have reached the conclusion that expansion of the anterior pouch and that of anterior ballooning are respectively attributed to slipping and anterior shift.

View full abstract

We studied the association of the risk of a rotator cuff injury with anatomical characteristics of sationary bony structures in order to determine whether the structural difference could account for the difference in susceptibility to a rotator cuff injury.
Twenty cadaver shoulders from 10 individua ls,6 men and 4 women, who had died at an average age of 82.1 years (range,63-96 years). Each shoulder was examined macroscopically, and the coracoacrimial distance (CAD) was measured. The rotator cuff and SAB were examined. With the acromi on, the morphological type was deteromined macroscopically, and the CAD was measured. The coraco-acromial minimum distance (CADm) was also measured. Radiographically, the slope angle (SA) was measured on a lateral view, and the acromion angle (AA) we defined. Each of the anatomical factors was examined statistically by the Student's test to determine whether it was correlated with the rotator cuff injury.
Rotator cuff i njury could be recognized macroscopically in 8 (40%) of the 20 shoulders. The acromion was morphology of Type I (flat) in 5 shoulders (25%), Type II (curved) in 9 (45%), and Type III (hooked) in 6 (30%). The CAD was 31.2±2.4mm on average in shoulders with rotator cuff in jury, but 37.2±3.2mm in shoulders without it (P<0.01). The means of CADm in Shoulders with and without rotator cuff injury were 22.4±2.7mm and 26.4±4.4mm, respectively, without a significant correlation between CADm and a rotator cuff injury. The mean SA in shoulders with and without a rotator cuff injury were 37.5±3.9° and 32.8±5.1°, respectively, without a significant correlation. Like the SA, the AA did not correlate with a rotator cuff injury. From these results, only the length of the coraco-acromial ligament was associated with rotator cuff injury; none of the other anatomical parameters, including the CADm, SA, and AA, were correlated to a rotator cuff injury.
To clarify the anatomical etiology of a rotator cuff injury, the stationary b ony structure of the shoulder was studied. The coraco-acromial distance reflects the features of the coraco-acromial arch, the site of the rotator cuff injury. The decreased coraco-acromial distance is one of anatomical factors related to the etiology of a rotator cuff injury.

View full abstract

Rotator interval (RI) tears are classified into two types: contracted and unstable types. The present study was undertaken to elucidate the morphologic changes of RI tears in patients in their 2nd and 3rd decades, which are mainly involved in the latter type.
Eight patients with RI tears, whose other intr aarticular structural abnormality was excluded by shoulder arthroscopy, were evaluated. There were 6 males and 2 females, aged from 16 to 28 years. Five patients were overthrow athletes. An inferior instability was found in 6 shoulders. Specimens taken from the lesions were examined histologically and the findings were compared with those in 5autopsy cases of 41 to 50 years of age.
Synovial hyperemia and proliferation in RI regions were observed arthroscopically in all the patients.
Histologic sections from RI tears showed fibrin deposits on the synovial surface and proliferated small vessels in the synovial layer in all the patients, and those deep in the ligament in 1 patient. The number of inflammatory cells were quite limited and proliferation of the lining cells was almost negligible. The swelling and irregularity of the fibers of the capsule and ligaments in the RI region were evident. There were no thick collagen bundles in the sections.
These results suggest that in RI tears of young patients, irregularity of the fibers of the capsule and ligament occurred, followed by reactive changes in the synovium and deep layer of the ligament, without any thick collagen bundle formation. This phenomenon may be correlated to the absence of a contracture of the shoulder joint.

View full abstract

[Purpose] To clarify preoperative clinical features and diagnostic imaging findings that let us predict primary reparability of a massive rotator cuff tear.
[Patients and Methods] Twenty-four patients (25 Shoulders) who underwent an operation for massive tears were divided into two groups. Group R consisted of 11 cases with reparable massive tears primarily, while group U was 14 cases with irreparable tears. The average age was 63 years in group R, and 63 years in group U (NS), as well. The average duration from onset to the operation was 10months in group R, and 42 months group U. Massive tear reparability at operation was judged by one senior anthor in all cases. The history, physical signs, X-rays, arthrograms and MRI findings were evaluated retrospectively.
[Results] The thickness of the supraspinatus (SSP) and infraspinatus (ISP) mucles in group R on MRI was significantly larger than in group U (p<0.05). The thickness of the fat layer between the trapezius (Tz) and the SSP in group R was significantly less than in group U (p<0.05). The incidence of primarily reparable cases was significantly high in cases with a thickness of SSP more than 18m m, ISP more than 14mm, and fat layer between Tz and SSP less than 10mm (p<0.05).
[Conclusion] The thick ness of the SSP and ISP muscle on MRI may be useful for prediction of primary reparability of a massive rotator cuff tear.

View full abstract

[Purpose] The purpose of this study was to evaluate the results of non-operative treatment for rotator cuff tears and to identify the prognostic indicators.
[Materials and methods] This study involved 40 patients with the mean age was 59.7 years (range 3179 years). There were 25 males and 15 females and average follow-up period was 21.0 months (range 12-63 months). The diagnosis was confirmed by arthrogram and MRI and 25 patients had full-thickness tears and 15 patients had incomplete tears. All shoulders were assessed retrospectively and scored using JOA shoulder scoring system.
[Results] The average JOA score at initial examination and at final follow-up were 62.9 and 82.3 in full-thickness tears, and 66.9 and 91.2 in incomplete tears respectively. The final scores were significantly better in incomplete tears. Of the 25 patients with full-thickness tears,16 (64%) were rated as satisfactory at the time of latest evaluation. Of the 15 Shoulders with incomplete tears,13 (87%) were rated as satisfactory. In the group with full-thickness tears, patients with small tears showed significantly better final results than those of patients with large tears. The initial scores were not correlated with the final scores significantly in each group.
[Conclusions] Non-operative treatment for incomplete rotator cuff tears showed good clinical outcomes. In the group of full-thickness tears, final results were worse in patients with large tears.

View full abstract

The findings of MR imaging (MRI) of patients with massive tears of the rotator cuff were evaluated. MR images of 27 shoulders of 26 patients with rotator cuff tears were taken before they were surgically treated. They were classsified as patched group (those repaired with a patch graft) or nonpatched group (those repaired without a patch graft). The length of the tear (oblique coronal view), the width of the tear (oblique sagittal view), the thickness of the supraspinatus (oblique coronal view) and their intensities in the infraspinatus (axial view) were statistically examined. The length of the tear avaraged 42mm in the patched group, and 22mm in the non: patched group. The width of the tear averaged 46mm in the patched group, and 23mm in the non-patched group. The thickness of the supraspinatus averaged 4.8mm in the patched group, and 8.7mm in the non-patched group. There was some significance between the two groups. Further in the patched group, a high signal intensity in the infraspinatus was characteristic statistically. The increase of the length and the width of the tear, the decrease of the thickness of the supraspinatus and a high signal intensity in the infraspinatus in the MRIs suggested that a patch graft was needed as the surgical treatment of rotator cuff tears.

View full abstract

We wish to report our experiences with surgical treament of the comminuted proximal humeral fractures and fracture-dislocations. Eighteen patients included nine three-part fracture/dislocations and nine four-part fracture-dislocations. There were four men and fourteen women, average aged 65 years (range 27 to 84 years). Eleven patients had nine three-part and two four-part fracture-dislocations, average aged 59 years, were operated on with osteosynthesis. Seven patients with four-part fracturedislocations average age 75 years, received a hemiarthroplasty. All the patients were evaluated with the JOA score at an averrage follow-up of 34 months. The average active elevation in the patients treated with osteosynthesis was 130°, external rotation was 28° and average JOA score was 85. Avascular necrosis occurred in three patients and non union in one. While the average active elevation in patients who had undergone a hemiarthroplasty was 107°, and external rotation was 25° and average JOA score was 78. In conclusion optimal results can be expected in the younger patients treated early and with a minimal internal fixation, although the results of osteosynthesis in those older patients with valgus intra-articular fracture were poor. Hemiarthroplasty provides a pain free shoulder, however recovery of range of motion and function are limited.

View full abstract

To improve the results of the operative treatment for a comminuted fracture of the proximal end of the humerus (3- and 4-part fracture of Neer' s classification), the author performed a clinical follow-up study about their surgical treament.
The JOA shoulder scoring system was used to evaluate them. Twelve patients with a 3-part Fx were treated by open reduction with an internal fixation (hereafter ORIF) with a mean age of 66.8 years demonstrated that the average ROM of shoulders was 138° in elevation and 38° in external rotation, T10 in internal rotation with an average JOA score of 89 at follow-up. Two patients with a 3-part Fx were treated by endoprosthesis replacement with a mean age of 56.3 years showed that the ROM was 160° in elevation,38° in external rotation, and an L2 in internal rotation with a JOA score of 87. Four patients with a 4-part Fx were treated with an ORIF with a mean age of 56.3 years demonstrated that the ROM was 124° in elevation,33° in external rotation, and T11 in internal rotation with a JOA score of 81 on average.
Five patients with a 4-part Fx were treated by endoprosthesis replacement with a mean age of 62.6years, the ROM was 103° in elevation,20° in external rotation, and L5 in internal rotation with a JOA score of 73.2 on average. Humeral head necrosis was found in 1 patient with a 4-part Fx and late wound infection was noted in 1 patient with a 4-part Fx treated by endoprosthesis. The results of the 3-part Fx were better than those of the 4-part and the results of ORIF were better than those of endoprosthesis replacement.
In the ORIF for a 3- and 4-part fracture, a bone graft should be added if necessary.

View full abstract

[Purpose] This is the follow-up study of humeral endo-prosthesis for 3-part fracture(3-pfx)and 4-part fracture(4-pfx)of proximal humerus.
[Method] Sixty cases of humeral endo-prostheses were perfomed for 3-pfx and 4-pfx of proximal humerus between 1976 and 1998. Thirty cases consisting of postoperative period over two years were evaluated by JOA Scoring System. Neer prosthesis was used in 3 and Kyosera prosthesis was used in 27 in this evaluation. The follow-up period ranges from two years to 18 years and 10 months, average of 8 years and 2 months.
[Results] 1. Thirty cases consist of 6 males and 24 females, and 17 were left and 13 were right shoulder. At the time of injury, patient's age were between 25 and 84 year old (average 61 year old). The types of fracture consist of four 3 - pfx, four 3 - pfx - disl, seventeen 4 - pfx and five 4 - pfx - disl. Infection occurred in only one and prosthesis was removed.
2. Rating of the result by JOA Scoring System revealed 10 for excellent (above 90 points),11 for good (80 - 89),1 for fair(70-79)and 8 for poor(below 69).70% were rated higher than “good” and average score were 80.7. The time from injury to surgery exceeded one month in 4 cases and 3 of these 4 cases were rated poor.3. Post - operative range of abduction was above 120° in 13 cases,90° to 119° in 10 and below 89° in 7. External rotation was above 30° in 10 cases,0° to 29° in 13 and below 0° in 7. The thumb reached to dorsal spine in 4 cases, to lumbar spine in 20 and to buttock in 6.4. X-ray evaluation: These were one migration of prosthetic head, one heterotopic ossificatioin, two high riding greater tubercle, two AHI narrowing and three fracture of prosthetic stem.
[Discussion] The affected to the results of endo-prosthes were as follows: 1. The time elapsed from injury to surgery.2. Improvement of rotation.3. X-ray findings such as migration of prosthetic head and high riding of greater tubercle.4. Post-operative rupture of rotator cuff.

View full abstract

[Purpose] The purpose of this study is to evaluate the MRI before and after Putti-Platt procedure for recurrent anterior dislocation of the shoulder.
[Materials and Methods] Between January 1992 and April 1998,6 shoulders of 6 patients (3 men and 3 women) received Putti-Platt procedure were evaluated by the MRI before and after operation. The average age of these patients was 23.3 years (range,19-33) at operation and the average follow-up period was 15.2 months (range,4-42). Several images in the transverse and oblique planes - that is, perpendicular to the glenoid surface, were obtained. Then changes of the signal intensity were examined in the procedure. Then the area and volume of subscapularis tendons were measured by an NIH image software.
[Results] After a Putti-Platt procedure the subscapularis tendons were thickened and increased in signal area on T2 weighted images were observed in 4 patients. The area of subscapularis tendons after the operation was increased by 3.46 times on the largest (range: 1.48∼3.46) and the volume was increased by 1.51 times on the average (range: 1.29∼1.78). The course of the subscapularis muscle fiber before operation was described as a mild arc, but changed into straight direction after the procedure in 5 patients.
[Conclusion] The findings in this study suggest that Putti-Platt procedure leads to remarkable strength of the subscapularis tendon and improvement of laxity of subscapularis muscle. In conclusion, this procedure increases stability of the grenohumeral joint and is a successful treatment for recurrent anterior dislocation of the shoulder.

View full abstract

We have evaluated results of Boytchev's procedure for recurrent dislocation of the shoulder.
14 shoulders with recurrent anterior dislocation were evaluated. There were 10 male s and 4 females with a mean age of 28.4 years (range,18-50 years). The average follow-up was 67 months (range.24168 months). We adopted a simple procedure of Boytchev with two tendons; The short head of biceps muscles and the coracobrachial muscle. We evaluated the redislocation, the apprehention test, the external rotation, and the JOA scores. There were no redislocations postoperatively.7 cases occurred were sports injuries. The mean limitation of external rotation was 5.7°. The average JOA score was 93 points. There were 12 cases with more than 90 points. There was a case of muscle cutanial nervepalsy postoperatively, but it recovered two years later. There was a case of a coracoid bone-chip fracture in the middle of rehabilitation, which healed too. All the patients returned to their original work or sports.
We had good results using Boytchev's procedure for a recurrent dislocation of the shoulder.

View full abstract

[Purpose] In our previous study, we evaluated the pathological changes in the subacromial surface. In this study, we used an electron microscope.
[Methods] 32 patients (24 men and 8 women) aged from 22 to 80 (mean: 61.4).8 had no cuff tears, there were complete tears in 24. Isolated subacromial surface was stained with HE and pH4.1 T. B., and with elastin histochemically, then observed under a light microscope. Coracoacromial ligament was observed under a transmission electron microscope.
[Results] The synovial membrane layer was lost in all patients with intact rotator cuffs, the degree of alteration was limited to the fibrocartilaginous layer, and was mainly related to age. Patients with a cuff tear showed various changes, and the degree of alteration was more related to the depth or extent of the tear. The incidence of rough fiber in the coracoacromial ligament increased with age. Changes in the coracoacromial ligament were observed under elastin staining and transmission electron microscope were more closely related to age, as well.
[Conclusion] Rotator cuff tear causes secondary pathological changes to the subacromial surface, however, the change of the coracoacromial ligament was mainly related to age.

View full abstract

The purpose of this study is to describe the relationship between the morphology of the acromion and rotator cuff tear seen on MR imaging. MR imaging of 210 shoulders were examined. There were 92shoulders with complete rotator cuff lesions. We classified acromion shape on T2-weighted sagital obleque view of MRI. Morphologic types of acromions were defined according to the Neer classification (Type I: flat, Type H: smoothly curved, Type III: hooked).
The relationship between acromion shape and cuff tear was examined. MR examinations were performed on a 0.5-tesla magnet (T5-II, Phillips ).
Of all cases 41.9% had Type I acromion,36.7% had Type II and 21.4% had Typa III. Among the cuff tear cases the prevalence of Type I was 35.9%, Type II was 23.9% and Type III was 40.2%. There was a little tendensy that Type III was more likely seen in the case of cuff tear. The average of longitudenal cuff tear size had a close relation with morphology of acromion. Type ifi had a significantly biggger cuff tear size than Type I and Type II.

View full abstract

[Purpose] After shoulder surgery, postoperative pain is severe and is frequently difficult to relieve a dequately.. In this study, we examined the efficacy of continuous subcutaneous infusion of Bupurenorphine Hcl as a postoperative pain management.
[patients] 30 patients who were scheduled to have an elective shoulder procedure were entered in this study.
[Methods] Bupurenorphine Hcl 1.2mg and Physiological saline 20m1 filled a Baxtre Infusor and were infused for 48 hours in a precordinal subcutaneous tissue. As pain occurred, the patients could administer the postoperative analgesics to themselves with a device that they controlled in addition to the continuous infusion.
[Results] The average periods required to manage pain was 2.50days for a rotator cuff tear,2.14 days for shoulder instability, and 2.00 days for the others. However, side effects like nausea and headaches, were observed in some cases.
[Conclusion] Several groups have reported on the efficacy of a continuous cervical epidural block as well, this method could not be identified as the prevalent method. For shoulder surgery, continuous subcutaneous infusion, with the technique in which patients an control their own pain, it is one of the more effective postoperative pain managements.

View full abstract

[Purpose] To detect changes in the shoulder after throwing with MRI and Dynamic MRI.
[Subjects and Methods] We studied 10 shoulder joints in 10 baseball players aged 20 to 22 who were members of a university baseball club using an 0.3-tesla MR unit before and after throwing. Each player threw a baseball 200 times as hard as he could. Following a first, non-enhanced image (T1weighted, T2* -weighted), Gd-DTPA was administered intravenously. Gradient echo images were then obtained every 30 seconds, for a total period of 11 minutes. The signal intensity changes for the first 11 minutes were used to calculate the coefficient of enhancement (CE) in regions of interest.
[Results and Discussion] The muscular portion of the subscapularis and supraspinatus were larger after than before throwing, But the deltoid and infraspinatus did not change remarkably. The CE in the anterior and posterior portion of the SAB were higher than those in the rotator interval and middle portion of the SAB. These changes were caused by repetitive throwing. Our findings show that it is possible to objectively evaluate the stress on the shoulder joint caused by throwing using MR imaging.

View full abstract

[Purpose] This report presents our results on treating an acromioclavicular (A-C) joint dislocation by reconstruction of the coracoclavicular (C-C) ligament in the anatomical site and restorating of the ruptured disc.
[Materials and Methods] We treated thirteen A-C joint dislocations from May 1990 to December 1997. The coracoacromial (C-A) ligament was dissected free of soft tissue and detached from the acromion with the bone block (10×10×5 mm) at operation. A7mm drill hole was made through the upper part of the C-C ligament of the clavicle. Transacromial fixation was done with two 1.8mm Kirschner wires. One of them acted to fix the bone block in the clavicle. The disc and capsule of the A-C joint were repaired using absorbable sutures. A Desault bandage was applied for one week and a sling was worn for 2weeks. The pendulum exercise was started at 4 weeks and two Kirschner wires were pulled out 7 weeks after surgery.
[Results] The average forllow up period was 2 years 7 months. The results of this procedure were good. But two cases had an osteophyte at the A-C joint. One case dislocated slightly due to the initial inadequate fixation. But now there are no clinical troubles.
[Conclusion] Repairing the tuptured disc and transfering the C-A ligament with a bone block into the anatomical site of the clavicle through the drill hole is an excellent operation.

View full abstract

Resection of the first rib through the transaxillary approach for thoracic outlet syndrome was performed on those patients whose symptoms were not relieved by conservative treatment in our institut es. The purpose of this study is to evaluate the clinical results of this procedure.
35 arms of 31 patients were followed-up.9 patients were male and 22 patients were female. The average age at the operation was 26 years old. The average follow-up period was 1 year and 7 months. We classified the preoperative symptoms into three groups according to Tateishi's Classification, and investigated the relationship between these groups and the clinical results. We also investigated the relationship between the appearance of DSA and the clinical results.
The overall results were excellent in 10 arms, good in 18 arms, fair in 6 arms, and poor in 1 arm. The relief of subjective symptoms in the upper extremity was better than that in the neck and shoulder. The degree of compression of the subclavicular artery in DSA at arm in abduction did not affect to the clinical results.
We attribute our good results to confirmation of the compression of the subclavicular artery in DSA at the arm in abduction. We consider that the resection of the first rib is a good procedure for thoracic outlet syndrome, especially, for those who have subjective symptoms of the upper extremities. But we required careful surgical indication for those who have the subjestive symptoms of a shoulder girdle, if they had a compression of the subclavicular artery in DSA who the arm was in abduction.

View full abstract

[Purpose] Recurrent anterior dislocation of the shoulder in elderly patients has seldom been reported, and the pathologic features of this group have not been fully clarified in the literature. The purpose of this study was to report our operative findings and to investigate the etiology of the recurrent anterior dislocation of the shoulder with onset after the age of 50.
[Materials and Methods] We retrospectively studied nine patients who were over 50 years old at the time of initial traumatic dislocation and then who had recurrent instability of the shoulder. We evaluated the operative findings as follows: rotator cuff tear, Bankart lesion, anterior capsular injury. One patient was treated with the Putti-platt method and three had inferior capsular shifts. The other five patients were treated with a Bankart repair. In addition to those operations, seven of them were treated with a modified Bristow method.
[Results] Rotator cuff tears were seen in 5 patients, and four of them were massive tears with a subscapularis rupture. There was an elongation of the subscapularis in the other patient. Bankart lesions were seen in 5 patients with a bony lesion. The other 4 patients had abnormal lesions of the anterior capsule.
[Conclu sion] In elderly patients, destruction of the shoulder anterior stability structure including the sabscapularis should be considered as one of the main causes of recurrent anterior dislocations.

View full abstract

[Purpose] Bankart lesions in recurrent dislocation or subluxation and initial dislocation of the shoulder were compared by typing of Bankart lesion of MR arthrogram (MRA). MR arthrographic (MRA) typing.
[Material and Methods] The subjects were 79 patients (80 Shoulders) with recurrent dislocation( 47Shoulders) or subluxation (33 Shoulders) of the shoulder who underwent MRA in our department between August 1991 and May 1998. The patients ranged in age from 14 to 80 years with a mean of 27.7years. The history of dislocation or subluxation was 3 times in 15 shoulders,4-9 times in 29 shoulders, and 10 or more times in 36 shoulders. Bankart lesion (B-L) was evaluated by MRA according to Hirose's classification ( Type Na, Nb, la, lb,2,3 ). MRA findings in patients with initial anterior dislocation reported by Hirose (1998) were examined as references. The B-L type was compared ( 1 )between the initial dislocation and recurrent dislocation or subluxation, ( 2 ) between recurrent dislocation and subluxation, and ( 3 ) according to the number of past dislocations.
[Results] 1. Types 1a and 1b tended to be reduced, and types 2 and 3 to be increased, in recurrent dislocation or subluxation compared with an initial dislocation of the shoulder.2. There were no differences in the B L type between a recurrent dislocation and subluxation.3. Although the injury types involving the anterior glenoid labrum (type 1 a, type 1 b, type 2) were not related to the number of dislocations, type 3 (bony Bankart) increased with the number of dislocations.
[Conclusion] The morphology of anterior glenoid labrum injuries is determined while the number of recurrences of shoulder dislocation is still small. On the other hand, as a recurrence of dislocation of 3 times or more did not affect the morphology of a glenoid labrum injury, the number of recurrences is considered to be related to disruption of the anterior capsular mechanism other than the glenoid labrum.

View full abstract