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Synovial chondromatosis of the subacromial bursa with rotator cuff tearing
Synovial chonclromatosis of the subacromial bursa with rotator cuff tearing Jih-Yang Ko, MD, Jun-Wen Wang, MD, Wei-Jen Chen, MD, and Ryuji Yamamoto, MD, PhD, Kaohsiung, Taiwan, and Yokohama,Japan
Synovial chondromatosis is an unusual monoarticular condition of the synovial membrane of the joint and may occasionally involve the bursae and tendon sheaths. 5' 7. 9, 11, 12 Although the disease most often affects the knee, elbow, or hip joints, other joints such as the wrist, ankle, shoulder, and the small joints of the hand may be involved. The condition usually presents as dull aching pain and crepitation in the involved joint. Diagnosis is frequently delayed until numerous loose bodies accumulate, which are demonstrated on roentgenographs. We report a case of synovial chondromatosis in the subacromial bursa of the right shoulder of a 46-year-old housewife. The major symptoms were crepitation of the right shoulder during movement in all directions for 4 years and painful discomfort for 6 months. No history of trauma was reported. Prolonged existence of the loose bodies caused rupture of the rotator cuff. Unusual multiple slitlike tears were noted during the operation. Anterior acromioplasty, total removal of the loose bodies, partial bursectomy, and rotator cuff repair rendered the patient free of symptoms. CASE REPORT A 46-year-old housewife was seen because of progressive painful discomfort that had been in her right shoulder for 4 years. In the beginning she reported a sound unaccompanied by pain in her right shoulder during movement. Painful discomfort developed 6 months before presentation. The pain From the Departments of Orthopedic Surgery and Pathology, Chang Gung Memorial Hospital, Kaohsiung, Taiwan; and The Department of Orthopedic Surgery, Showa UniversityFujigaoka Hospital, Yokohama, Japan. Reprint requests: Jih-Yang Ko, MD, Department of Orthopedic Surgery, Chang Gung Memorial Hospital at Kaohsiung, 123, Ta-Pei Rd., Niao-Sung, Kaohsiung, Taiwan. J ShouLDERELBOWSURG1995;4:312-6. Copyright 9 1995 by Journal of Shoulder and Elbow Surgery Board of Trustees. 1058-2746/95/$3.00 + 0 3 2 / 1 / 6 1 6 0 5
312
was also present at night and disturbed her sleep. No history of trauma was reported, and other joints were not involved. She visited many physicians, but no definite diagnosis and treatment were given, although some radiographs were taken. On examination severe pain and crepitation beneath the right acromion on movement were noted. The values for active range of motion in flexion, extension, abduction, and external rotation were 130 ~ 15 ~ 110 ~ and 20 ~ respectively. The values for passive range of motion in flexion, extension, abduction, and external rotation were 170 ~, 25 ~, 160 ~, and 35 ~. The internal rotation was to the gluteal level. Intact sensation was present, but muscle power around the right shoulder girdle could not be tested accurately because of pain. Injection of 10 ml of lidocaine hydrochloride (Xylocaine) into the subacromial bursa relieved the pain. The passive range of motion in flexion, extension, abduction, and external rotation increased to 175 ~ 30 ~ 170 ~ and 40 ~ The internal rotation improved to the T12 level. Hematologic and biochemical tests were normal. The chest radiograph was negative. Radiographs of her shoulder joint revealed numerous, discrete, rounded, radiopaque bodies in both the subacromial bursa and the glenohumeral joint (Figure 1). A glenohumeral joint double-contrast computed arthrotomogram delineated the leakage of air and dye into the subacromial bursa and the presence of masses of calcified bodies both in the subacromial bursa and glenohumeral joint (Figure 2). The study also suggested complete thickness tearing of the rotator cuff. Because of the pain, multiple loose bodies, and rotator cuff tearing, surgical intervention was performed. A saber incision was made extending from just lateral to the anterior acromion to a point one fingerbreadth lateral to the coracoid. After mobilization of the subcutaneous tissue was done, a split was made by blunt dissection in the deltoid
J. Shoulder Elbow Surg. Volume 4, Number 4
Ko et al.
313
Fi~lure 1 Radiograph af right shoulder revealed numerous,discrete, rounded, raaiopaque bodies in both subacromid bursa and glenohumerd ieint.
Figure 2 Glenohumeral double-contrast computed arthrotomogram of right shoulder delineated leakage of air and dye into subacromial bursa and presence of massesof calcified bodies both in subacromial bursa larrow) and alenohumeral joint. muscle extending from the acromioclavicular joint capsule downward 3 cm. The distal end of this split in the deltoid was secured with a stay suture to prevent further splitting. With sharp dissection a flap of deltoid muscle was raised off the anterior acromion to expose the coracoacromiai ligament. Anterior acromioplasty and coracoacromial liga-
ment excision were performed with the technique described by Neer. ~ Multiple loose bodies of ossified chondroid material were seen in the subacromial bursa. The sizes ranged from a few millimeters to more than 1 cm in diameter (Figure 3). These loose bodies were removed. The bursa was noted to be thickened, inflamed, and studded with
314
J. Shoulder Elbow Surg. July~August 1995
Ko etal.
Figure 3 Anterior acromioplasty and coracoacromial ligament excision were performed during operation. Multiple loose bodies of ossified chondroid material were in subacromial bursa. Sizes ranged from a few millimeters to more than 1 cm in diameter.
Figure 4 Tears of rotator cuff (arrows) were different from those commonly present in that they were slitlike, were perpendicular to axis of supraspinatus and infraspinatus tendons, and were not in the critical zone. These ruptures were presumably caused by direct pressure and irritation of loose bodies. cartilaginous bodies. Partial synovectomy was performed. In addition, four complete-thickness tears and multiple, small, partial tears of the rotator cuff involving the supraspinatus and infraspinatus tendons were identified. These tears were different
from those commonly seen in that they were slitlike, were perpendicular to the axis of the tendons, and were not in the critical zone (Figure 4). These ruptures were presumed to be caused by direct pressure and irritation of the loose bodies.
J. Shoulder Elbow Surg. Volume 4, Number 4
Ko etal.
315
Figure 5 Micrograph of synovial nodule demonstratescartilaginous metaplasia (M) beneath synovial surface (arrow). (Hematoxylin-eosin stain, original magnification x150.) Through the torn cuff another six loose bodies were enucleated from the glenohumeral joint. The completely ruptured areas were sutured directly. No repair was performed for the multiple, small, partial tears. Microscopic examination of the synovial nodules showed cartilaginous metaplasia beneath the synovium (Figure 5). A Velpeau's bandage was applied for temporary immobilization after the operation. Early passive motion exercises were performed twice daily beginning 2 days after the operation. On the fourth day passive external rotation exercises were added. On the fifth day self-assisted exercises including the use of a pulley, external rotation with a stick, and internal rotation were added. The patient was discharged from the hospital on the sixth day on a program of self-assisted exercises. Active exercises were started the fourth week after the operation. She gained full muscle power and range of motion with mild residual pain by 3 mo~ths after the operation. The residual pain disappeared 6 months after the operation. Two years later the patient had no symptoms and a normal range of motion of her right shoulder. Radiographs of the right shoulder did not show any evidence of recurrence of the loose bodies.
DISCUSSION Synovial chondromatosis most commonly affects the knee joint followed by the hip, ankle, and
elbow.S, 12 However, all synovia including those of joint sheaths and bursae can be affected by this process.9, ~1 Although the pathogenesis is poorly understood, this process begins in cells underlying the epithelial layer of the synovium. Cartilaginous islands are formed by metaplasia of pluripotential cells in the synovial membrane. Pedunculation of these cartilaginous foci often leads to autoamputation of fragments of cartilage and the proliferation of loose bodies within the joint. ~-3' 11 Milgram 4 postulated three recognizable phases of synovial chondromatosis: (1) active intrasynovial disease without loose bodies, (2) transitional lesions with active intrasynovial proliferation and loose bodies, and (3) multiple loose bodies with no demonstrable intrasynovial disease. Clinical manifestations of synovial chondromatosis include pain, swelling, limited motion, crepitus, locking, and occasionally, palpable loose bodies. 1" 12 Because the symptoms and signs are nonspecific, the diagnosis may not be easy to establish. Therefore early diagnosis requires a high index of suspicion and a detailed examination. The condition may be undiagnosed for several years until numerous loose bodies accumulate and cause obvious symptoms or the radiopaque bodies are demonstrated with roentgenography. Our patient reported persistent crepitation and gradually intensifying discomfort in the subacromial space of the right shoulder for 4 years.
316
J. Shoulder Elbow Surg. July~August 1995
Ko et al.
Radiographic findings depend on the stage of the disease and range from normal findings to the presence of multiple, radiopaque, free, calcified bodies in the joint cavity. Differential diagnoses include degenerative arthritis, neurotrophic arthritis, osteochondritis dissecans, osteochondral fractures, rheumatoid arthritis, and tuberculous arthritis. These conditions are differentiated histologically from synovid chondromatosis by their lack of cartilaginous metaplasia in the synovial membranes.S. 12 In this particular case, however, calcified tendinitis of the rotator cuff should also be considered. Usually located in a dependent part or recess, the calcification of the synovial chondromatosis is multiple and as such can be easily differentiated from calcified tendinitis of the rotator cuff. Because numerous radiopaque bodies were in both the subacromial bursa and the glenohumeral joint, a double-contrast computed arthrotomogram of the glenohumeral joint was performed. It showed both the loose bodies and the tearing of the rotator cuff. A few articles deal with synovial chondromatosis of the shoulder girdleT' 7, 8, 11 Paul and Leach 7 reported two cases of synohial chondromatosis involving the shoulder joint. In one patient in whom many loose bodies were present, the humeral head and glenoid surface were gouged in multiple areas as the osteochondral bodies impinged between the opposing articular surfaces. 7 Hjelkrem and Stanish 2 reported a case of a 20-year-old man who had right shoulder pain for 6 months. During the operation the articular surface revealed moderate degenerative changes of the humeral head. Symeonides 1~ found two patients with synovial chondromatosis involving the bursae surrounding the shoulder. In a review of the world's literature he also found a case involving the axillary bursa and presented another case of his own involving the subdehoid bursa. In this patient no communication occurred between the subdehoid bursa and the shoulder joint. Although the natural history of the disease is one of slow progression and a tendency toward eventual resolution, 2' 3 erosion of the bone about the joint by the loose bodies can occur. The treatment most often advocated is arthrotomy, including removal of all loose bodies, and synovectomyZ' 8, 12 The results of treatment are dependent on the stage
of the disease during which treatment is given. Assuming no secondary degenerative arthritis exists, results are gratifying, if all the loose bodies are removed, and the remaining synovium is quiescent. A secondary arthritis frequently does exist when the patient is first seen; this arthritis greatly modifies the end result, particularly when weightbearing joints are involved. The characteristic features of our case included disease onset at a relatively young age, a lack of history of trauma or heavy work, painless crepitation for 31/2 years, and intraoperative findings of unusual slitlike tendon tears. These features suggested that the rotator cuff tearing was caused by persistent existence of the loose bodies in the subacromial bursa. Prolonged crepitation beneath the acromion requires further investigation, if the symptoms do not improve after conservative treatment. It is our suggestion that early diagnosis and treatment are imperative to shorten the patient's morbidity and to avoid rupture of the rotator cuff. REFERENCES
1. HardackerJ, Mindelt ER. Synovial chondromatosiswith sec ondary subluxationof the hip: a casereport.J BoneJointSurg Am 199 ] ;73A: 1405-7. 2. H elkremM, StanishWD. Synovialchondrometaplasiaof the shouder: a case report of a young athlete presentingwith shoulder pain. Am J SportsMed 1988;16:84-6. 3. Jeffreys TE. Synovial chondromatosis.J BoneJoint Surg Br 1967;49B:530-4. 4. Milgram JW. Synovial osteochondromatosis: a histopatho logical studyof thirtycases.J BoneJointSurgAm 1977;59A: 792-801. 5. MurphyFP, Dahlin DC, Sullivan CR. Articularsynovial chondromatosis. J BoneJoint SurgAm 1962;44A:77-86. 6. Neer CSII. Anterior acromioplaslyfor the chronic impingementsyndromein the shoulder: a preliminaryreport.J Bone Joint SurgAm 1972;54A:41-50. 7. PaulGR, LeachRE. Synovialchondromatosisof the shoulder. Clin Orthop 1970;68:130-5. 8. RichmanJD, RoseDJ. The role of arthroscopyin the managementof synovid chondromatosisof the shoulder.Clin Orthop 1990;257:91-3. 9. Sim FH, Dehlin DC, IvinsJC. Extra-articularsynovial chondromatosis. J BoneJoint $urg Am 1977;59A:492-5. 10. Symeonides R Bursal chondromatasis.J BoneJoint Sur,g Br 1966;48B:371-3. 11.. Volpin G, Nerubay J, Oliver S, Katznelson A. Synovial osteochondromatosisof the shoulder joint. Am Surg 1980; 46:422-4. 12. Wilson WJ, ParrTJ. Synovial chondromatosis.Orthopedics 1988;] 1:1179-83.
Synovial chondromatosis is an unusual monoarticular condition of the synovial membrane of the joint and may occasionally involve the bursae and tendon sheaths. 5' 7. 9, 11, 12 Although the disease most often affects the knee, elbow, or hip joints, other joints such as the wrist, ankle, shoulder, and the small joints of the hand may be involved. The condition usually presents as dull aching pain and crepitation in the involved joint. Diagnosis is frequently delayed until numerous loose bodies accumulate, which are demonstrated on roentgenographs. We report a case of synovial chondromatosis in the subacromial bursa of the right shoulder of a 46-year-old housewife. The major symptoms were crepitation of the right shoulder during movement in all directions for 4 years and painful discomfort for 6 months. No history of trauma was reported. Prolonged existence of the loose bodies caused rupture of the rotator cuff. Unusual multiple slitlike tears were noted during the operation. Anterior acromioplasty, total removal of the loose bodies, partial bursectomy, and rotator cuff repair rendered the patient free of symptoms. CASE REPORT A 46-year-old housewife was seen because of progressive painful discomfort that had been in her right shoulder for 4 years. In the beginning she reported a sound unaccompanied by pain in her right shoulder during movement. Painful discomfort developed 6 months before presentation. The pain From the Departments of Orthopedic Surgery and Pathology, Chang Gung Memorial Hospital, Kaohsiung, Taiwan; and The Department of Orthopedic Surgery, Showa UniversityFujigaoka Hospital, Yokohama, Japan. Reprint requests: Jih-Yang Ko, MD, Department of Orthopedic Surgery, Chang Gung Memorial Hospital at Kaohsiung, 123, Ta-Pei Rd., Niao-Sung, Kaohsiung, Taiwan. J ShouLDERELBOWSURG1995;4:312-6. Copyright 9 1995 by Journal of Shoulder and Elbow Surgery Board of Trustees. 1058-2746/95/$3.00 + 0 3 2 / 1 / 6 1 6 0 5
312
was also present at night and disturbed her sleep. No history of trauma was reported, and other joints were not involved. She visited many physicians, but no definite diagnosis and treatment were given, although some radiographs were taken. On examination severe pain and crepitation beneath the right acromion on movement were noted. The values for active range of motion in flexion, extension, abduction, and external rotation were 130 ~ 15 ~ 110 ~ and 20 ~ respectively. The values for passive range of motion in flexion, extension, abduction, and external rotation were 170 ~, 25 ~, 160 ~, and 35 ~. The internal rotation was to the gluteal level. Intact sensation was present, but muscle power around the right shoulder girdle could not be tested accurately because of pain. Injection of 10 ml of lidocaine hydrochloride (Xylocaine) into the subacromial bursa relieved the pain. The passive range of motion in flexion, extension, abduction, and external rotation increased to 175 ~ 30 ~ 170 ~ and 40 ~ The internal rotation improved to the T12 level. Hematologic and biochemical tests were normal. The chest radiograph was negative. Radiographs of her shoulder joint revealed numerous, discrete, rounded, radiopaque bodies in both the subacromial bursa and the glenohumeral joint (Figure 1). A glenohumeral joint double-contrast computed arthrotomogram delineated the leakage of air and dye into the subacromial bursa and the presence of masses of calcified bodies both in the subacromial bursa and glenohumeral joint (Figure 2). The study also suggested complete thickness tearing of the rotator cuff. Because of the pain, multiple loose bodies, and rotator cuff tearing, surgical intervention was performed. A saber incision was made extending from just lateral to the anterior acromion to a point one fingerbreadth lateral to the coracoid. After mobilization of the subcutaneous tissue was done, a split was made by blunt dissection in the deltoid
J. Shoulder Elbow Surg. Volume 4, Number 4
Ko et al.
313
Fi~lure 1 Radiograph af right shoulder revealed numerous,discrete, rounded, raaiopaque bodies in both subacromid bursa and glenohumerd ieint.
Figure 2 Glenohumeral double-contrast computed arthrotomogram of right shoulder delineated leakage of air and dye into subacromial bursa and presence of massesof calcified bodies both in subacromial bursa larrow) and alenohumeral joint. muscle extending from the acromioclavicular joint capsule downward 3 cm. The distal end of this split in the deltoid was secured with a stay suture to prevent further splitting. With sharp dissection a flap of deltoid muscle was raised off the anterior acromion to expose the coracoacromiai ligament. Anterior acromioplasty and coracoacromial liga-
ment excision were performed with the technique described by Neer. ~ Multiple loose bodies of ossified chondroid material were seen in the subacromial bursa. The sizes ranged from a few millimeters to more than 1 cm in diameter (Figure 3). These loose bodies were removed. The bursa was noted to be thickened, inflamed, and studded with
314
J. Shoulder Elbow Surg. July~August 1995
Ko etal.
Figure 3 Anterior acromioplasty and coracoacromial ligament excision were performed during operation. Multiple loose bodies of ossified chondroid material were in subacromial bursa. Sizes ranged from a few millimeters to more than 1 cm in diameter.
Figure 4 Tears of rotator cuff (arrows) were different from those commonly present in that they were slitlike, were perpendicular to axis of supraspinatus and infraspinatus tendons, and were not in the critical zone. These ruptures were presumably caused by direct pressure and irritation of loose bodies. cartilaginous bodies. Partial synovectomy was performed. In addition, four complete-thickness tears and multiple, small, partial tears of the rotator cuff involving the supraspinatus and infraspinatus tendons were identified. These tears were different
from those commonly seen in that they were slitlike, were perpendicular to the axis of the tendons, and were not in the critical zone (Figure 4). These ruptures were presumed to be caused by direct pressure and irritation of the loose bodies.
J. Shoulder Elbow Surg. Volume 4, Number 4
Ko etal.
315
Figure 5 Micrograph of synovial nodule demonstratescartilaginous metaplasia (M) beneath synovial surface (arrow). (Hematoxylin-eosin stain, original magnification x150.) Through the torn cuff another six loose bodies were enucleated from the glenohumeral joint. The completely ruptured areas were sutured directly. No repair was performed for the multiple, small, partial tears. Microscopic examination of the synovial nodules showed cartilaginous metaplasia beneath the synovium (Figure 5). A Velpeau's bandage was applied for temporary immobilization after the operation. Early passive motion exercises were performed twice daily beginning 2 days after the operation. On the fourth day passive external rotation exercises were added. On the fifth day self-assisted exercises including the use of a pulley, external rotation with a stick, and internal rotation were added. The patient was discharged from the hospital on the sixth day on a program of self-assisted exercises. Active exercises were started the fourth week after the operation. She gained full muscle power and range of motion with mild residual pain by 3 mo~ths after the operation. The residual pain disappeared 6 months after the operation. Two years later the patient had no symptoms and a normal range of motion of her right shoulder. Radiographs of the right shoulder did not show any evidence of recurrence of the loose bodies.
DISCUSSION Synovial chondromatosis most commonly affects the knee joint followed by the hip, ankle, and
elbow.S, 12 However, all synovia including those of joint sheaths and bursae can be affected by this process.9, ~1 Although the pathogenesis is poorly understood, this process begins in cells underlying the epithelial layer of the synovium. Cartilaginous islands are formed by metaplasia of pluripotential cells in the synovial membrane. Pedunculation of these cartilaginous foci often leads to autoamputation of fragments of cartilage and the proliferation of loose bodies within the joint. ~-3' 11 Milgram 4 postulated three recognizable phases of synovial chondromatosis: (1) active intrasynovial disease without loose bodies, (2) transitional lesions with active intrasynovial proliferation and loose bodies, and (3) multiple loose bodies with no demonstrable intrasynovial disease. Clinical manifestations of synovial chondromatosis include pain, swelling, limited motion, crepitus, locking, and occasionally, palpable loose bodies. 1" 12 Because the symptoms and signs are nonspecific, the diagnosis may not be easy to establish. Therefore early diagnosis requires a high index of suspicion and a detailed examination. The condition may be undiagnosed for several years until numerous loose bodies accumulate and cause obvious symptoms or the radiopaque bodies are demonstrated with roentgenography. Our patient reported persistent crepitation and gradually intensifying discomfort in the subacromial space of the right shoulder for 4 years.
316
J. Shoulder Elbow Surg. July~August 1995
Ko et al.
Radiographic findings depend on the stage of the disease and range from normal findings to the presence of multiple, radiopaque, free, calcified bodies in the joint cavity. Differential diagnoses include degenerative arthritis, neurotrophic arthritis, osteochondritis dissecans, osteochondral fractures, rheumatoid arthritis, and tuberculous arthritis. These conditions are differentiated histologically from synovid chondromatosis by their lack of cartilaginous metaplasia in the synovial membranes.S. 12 In this particular case, however, calcified tendinitis of the rotator cuff should also be considered. Usually located in a dependent part or recess, the calcification of the synovial chondromatosis is multiple and as such can be easily differentiated from calcified tendinitis of the rotator cuff. Because numerous radiopaque bodies were in both the subacromial bursa and the glenohumeral joint, a double-contrast computed arthrotomogram of the glenohumeral joint was performed. It showed both the loose bodies and the tearing of the rotator cuff. A few articles deal with synovial chondromatosis of the shoulder girdleT' 7, 8, 11 Paul and Leach 7 reported two cases of synohial chondromatosis involving the shoulder joint. In one patient in whom many loose bodies were present, the humeral head and glenoid surface were gouged in multiple areas as the osteochondral bodies impinged between the opposing articular surfaces. 7 Hjelkrem and Stanish 2 reported a case of a 20-year-old man who had right shoulder pain for 6 months. During the operation the articular surface revealed moderate degenerative changes of the humeral head. Symeonides 1~ found two patients with synovial chondromatosis involving the bursae surrounding the shoulder. In a review of the world's literature he also found a case involving the axillary bursa and presented another case of his own involving the subdehoid bursa. In this patient no communication occurred between the subdehoid bursa and the shoulder joint. Although the natural history of the disease is one of slow progression and a tendency toward eventual resolution, 2' 3 erosion of the bone about the joint by the loose bodies can occur. The treatment most often advocated is arthrotomy, including removal of all loose bodies, and synovectomyZ' 8, 12 The results of treatment are dependent on the stage
of the disease during which treatment is given. Assuming no secondary degenerative arthritis exists, results are gratifying, if all the loose bodies are removed, and the remaining synovium is quiescent. A secondary arthritis frequently does exist when the patient is first seen; this arthritis greatly modifies the end result, particularly when weightbearing joints are involved. The characteristic features of our case included disease onset at a relatively young age, a lack of history of trauma or heavy work, painless crepitation for 31/2 years, and intraoperative findings of unusual slitlike tendon tears. These features suggested that the rotator cuff tearing was caused by persistent existence of the loose bodies in the subacromial bursa. Prolonged crepitation beneath the acromion requires further investigation, if the symptoms do not improve after conservative treatment. It is our suggestion that early diagnosis and treatment are imperative to shorten the patient's morbidity and to avoid rupture of the rotator cuff. REFERENCES
1. HardackerJ, Mindelt ER. Synovial chondromatosiswith sec ondary subluxationof the hip: a casereport.J BoneJointSurg Am 199 ] ;73A: 1405-7. 2. H elkremM, StanishWD. Synovialchondrometaplasiaof the shouder: a case report of a young athlete presentingwith shoulder pain. Am J SportsMed 1988;16:84-6. 3. Jeffreys TE. Synovial chondromatosis.J BoneJoint Surg Br 1967;49B:530-4. 4. Milgram JW. Synovial osteochondromatosis: a histopatho logical studyof thirtycases.J BoneJointSurgAm 1977;59A: 792-801. 5. MurphyFP, Dahlin DC, Sullivan CR. Articularsynovial chondromatosis. J BoneJoint SurgAm 1962;44A:77-86. 6. Neer CSII. Anterior acromioplaslyfor the chronic impingementsyndromein the shoulder: a preliminaryreport.J Bone Joint SurgAm 1972;54A:41-50. 7. PaulGR, LeachRE. Synovialchondromatosisof the shoulder. Clin Orthop 1970;68:130-5. 8. RichmanJD, RoseDJ. The role of arthroscopyin the managementof synovid chondromatosisof the shoulder.Clin Orthop 1990;257:91-3. 9. Sim FH, Dehlin DC, IvinsJC. Extra-articularsynovial chondromatosis. J BoneJoint $urg Am 1977;59A:492-5. 10. Symeonides R Bursal chondromatasis.J BoneJoint Sur,g Br 1966;48B:371-3. 11.. Volpin G, Nerubay J, Oliver S, Katznelson A. Synovial osteochondromatosisof the shoulder joint. Am Surg 1980; 46:422-4. 12. Wilson WJ, ParrTJ. Synovial chondromatosis.Orthopedics 1988;] 1:1179-83.