Rotator cuff repair in spinal cord injury patients

Rotator cuff repair in spinal cord injury patients Richard L. Popowitz, MD, John E. Zvijac, MD, John W. Uribe, MD, Keith S. Hechtman, MD, Matthias R. Schu¨rhoff, MD, and Jeremy B. Green, BA, Coral Gables, FL

Previous studies on the treatment of rotator cuff tears in wheelchair-bound patients have concentrated on nonsurgical management. We conducted a retrospective review to determine the effectiveness of surgical repair of rotator cuff tears in spinal cord–injured patients. Five male patients with rotator cuff tears confirmed by physical examination and magnetic resonance imaging underwent rotator cuff repair. Two of eight shoulders were revisions. The patients were evaluated postoperatively with the American Shoulder and Elbow Surgeons Scoring System. These results were compared with preoperative functional assessment. Patients were given a subjective questionnaire to assess their overall experience. Postoperative range of motion improved in 6 of 8 shoulders. Strength was increased in 6 of 8 shoulders. Patients reported satisfaction with the results in 7 of 8 shoulders, and all 5 patients would recommend the procedure to other spinal cord injury patients. At recent follow-up, 7 of 8 shoulders returned to their preinjury level of function. Surgery for spinal cord injury patients with rotator cuff tears can improve their functional capability and autonomy while reducing their pain. Compliance with the demanding postoperative rehabilitation is essential; therefore proper patient selection is crucial for optimal results. (J Shoulder Elbow Surg 2003;12:327-32.)

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pinal cord injury (SCI) resulting in loss of lower limb function newly affects approximately 11,000 persons in the United States each year.21 An estimated 230,000 Americans live with SCI.6,21 An estimated 30% to 50% of SCI patients will have shoulder pain and dysfunction develop as a result of the excessive stress caused by locomotion, mobility, and prehension.1,7,12–16,19,20 A relatively mild shoulder problem will markedly decrease the SCI patient’s ability to maintain functional independence. From UHZ Sports Medicine Institute. Reprint requests: John E. Zvijac, MD, UHZ Sports Medicine Institute, 1150 Campo Sano Ave, Suite 200, Coral Gables, FL 33146. (E-mail: [email protected]). Copyright © 2003 by Journal of Shoulder and Elbow Surgery Board of Trustees. 1058-2746/2003/$35.00 ⫹ 0 doi:10.1016/S1058-2746(03)00035-1

There have been numerous retrospective studies confirming that shoulder pain is common among SCI patients.3,8,18,20 Some etiologies include shoulder muscle imbalance, rotator cuff tears, subacromial bursitis, avascular necrosis, and referred pain from a neurologic disorder.2 Only two clinical studies have addressed the issue of attempting surgical treatment for rotator cuff tears in SCI patients. Robinson et al18 reported on 6 paraplegic patients who had subacromial decompression, 3 of whom had concurrent favorable rotator cuff repairs. Conversely, Goldstein et al8 reported on 4 patients (5 shoulders) with large rotator cuff tears who showed no improvement in shoulder function or active range of motion after surgical repair. The purpose of the current study is to evaluate the results of rotator cuff repair in the SCI patient to demonstrate the postoperative implications for the patient and to determine if it is a feasible treatment option. MATERIALS AND METHODS We identified 6 SCI patients with surgically repaired rotator cuff tears between 1994 and 2000. One patient was lost to follow-up. All records of patients included in the study were reviewed to confirm that a rotator cuff tear had been diagnosed by both physical and magnetic resonance imaging (MRI) examinations. The study population comprised 5 male patients with 8 involved shoulders. Patients ranged in age from 41 to 57 years (mean, 48.6 years) at the time of surgery. The level of SCI ranged from C5 to T10. One patient had incomplete quadriplegia, and the other four had paraplegia. The dominant extremity was involved in 5 of 8 shoulders. The mechanism of injury involved overuse in 6 shoulders, weight lifting in 1, and a motor vehicle accident in 1. Pain, weakness, and decreased active motion were the preoperative complaints in all shoulders. Of 8 shoulders, 2 displayed radiographic evidence of superior migration of the humeral head. After nonoperative treatment consisting of nonsteroidal anti-inflammatory drugs and physical therapy (PT), including strengthening and stretching exercises for a mean duration of 1.5 months (range, 1-3 months), the patients elected to have surgical repairs. The duration of symptoms before surgery ranged from 1 month to 3 years (mean, 5.9 months). Before surgery, each patient was given the American Shoulder and Elbow Surgeons (ASES) Standardized Form for Assessment of the Shoulder, and their Shoulder Score Index was calculated based on the data collected (Table I). All 8 shoulders underwent arthroscopy

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Table I Summary of pre-operative and post-operative shoulder status Active range of motion

Strength

Case Status

Side

ASES score

External Internal Abduction Flexion rotation rotation

Preop Postop 48 mo Preop Postop 33 mo

Left Left Right Right

21.7 95.1 21.7 90.1

160° 160° 140° 160°

120° ° 140° 160°

65° 45° 55° 45°

4/5 T10 T8 T9

4⫹/5 5/5 4⫹/5 5/5

4⫹/5 5/5 5/5 5/5

4⫹/5 5/5 5/5 5/5

5/5 5/5 5/5

Preop Postop 48 mo Preop Postop 24 mo

Right Right Left Left

61.7 92.6 54.2 85.1

155° 170° 140° 160°

155° 170° 145° 165°

60° 80° 55° 65°

L2 T10 L4 T12

4/5 5/5 3/5 4⫹/5

4/5 5/5 4/5 4⫹/5

4/5 5/5 4/5 4⫹/5

5/5 5/5 5/5 5/5

Preop Postop 12 mo

Right Right

31.7 58.4

150° 175°

80° 160°

65° 55°

T10 T9

3/5 3/5

5/5 5/5

4/5 4⫹/5

5/5 5/5

Preop Postop 9 mo Preop Postop 28 mo

Right Right Right Right

23.4 60.0* 21.7 93.4

120° 180° 150° 170°

115° 180° 150° 170°

50° 55° 60° 90°

T11 T10 T10 T9

4⫹/5 5/5 4⫹/5 5/5

5/5 5/5 5/5 5/5

4⫹/5 5/5 4⫹/5 5/5

5/5 5/5 5/5 5/5

34.1 100

160° 170°

160° 170°

90° 90°

T4 T6

4⫹/5 4⫹/5

5/5 5/5

4⫹/5 5/5

5/5 5/5

34.1

147°

133°

62°

84.3

168°

167°

66°

Supraspinatus

External Subscapularis rotation Deltold

1

2

3

4

5 Preop Postop 72 mo Preoperative mean Postoperative mean

Left Left

Preop, Preoperatively; Postop, postoperatively. *Nine months after rotator cuff repair and six months after bicep tendon repair.

followed by rotator cuff repair through a mini-open deltoidsplitting incision. After routine mobilization of the rotator cuff, tendon-to-bone repair was accomplished in 6 of 8 shoulders and tendon-to-tendon in 2. The surgical procedure described by Zvijac and Seltzer23 was used in all cases. Postoperative rehabilitation consisted of passive rangeof-motion exercises for the initial 6 weeks, followed by gradual active assisted and, beginning in week 8, active motion. Transfers were prohibited until 10 weeks after the procedure. Isometric exercises were begun at 8 weeks, followed by progressive isotonic exercises at 10 weeks postoperatively. All patients were afforded the same postoperative rehabilitation options (inpatient vs outpatient), and they chose according to their individual situations at home. All patients were followed up by an independent observer. Follow-up ranged from 12 to 72 months (mean, 40.6 months). The ASES form was again used to evaluate shoulder pain, function, range of motion, and stability.17 A postoperative Shoulder Score Index was calculated for each shoulder.

RESULTS Three illustrative cases are presented. The mean increase in the Shoulder Score Index for all 5 patients was 50.2 (Table I).

Case 1

A 44-year-old, right hand– dominant male painter who had become an incomplete C5-6 quadriplegic in 1972 had a 2-month history of left shoulder pain on presentation. The pain prevented transfers, overhead activities, and wheel chair propulsion, severely inhibiting his activities of daily life (ADLs). The preoperative motion on the left side was 160° of abduction, 120° of flexion, 65° of external rotation, and internal rotation to T8; on the right side, it was 165° of abduction, 130° of flexion, 65° of external rotation, and internal rotation to T8. The deltoid and rotator cuff, which are usually innervated by C5, were only partially affected because of the incomplete SCI. The patient had a level of strength of 4⫹/5 with manual muscle testing in all planes except the supraspinatus, where he had a strength level of 4/5 with pain. He had 1 month of nonoperative therapy including stretching and strengthening exercises, massage, and nonsteroidal anti-inflammatory drugs without any improvement in symptoms. An MRI study revealed a complete tear at the insertion of the supraspinatus tendon 2 cm in the transverse dimension without significant retraction. Two months after initial presentation, the patient un-

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derwent arthroscopy followed by repair of the supraspinatus tendon through a mini-open deltoid-splitting incision with the use of sutures through a bone trough. Approximately 1 year after the left rotator cuff repair, he had a 1-month history of right shoulder pain on presentation. His active motion was 140° of abduction, 140° of flexion, 55° of external rotation, and internal rotation to T8. His level of strength was 5/5 in all planes except the supraspinatus muscle, where he had a strength level of 4⫹/5 with pain. Radiographic findings were negative. An MRI examination revealed a full-thickness tear of the supraspinatus tendon. Three months after presentation, he underwent arthroscopy and repair of the supraspinatus tear, which was 2 cm in the anteroposterior dimension with 1.5 cm of medial-lateral retraction, through a mini-open deltoid-splitting incision with the use of sutures in a vertical figure-of-8 fashion through a bone trough. During arthroscopy, a 20% tear of the proximal biceps tendon was also visualized and debrided. After each surgery, the patient received professional assistance for morning and evening transfers and ADLs. Six months after the procedures, both shoulders returned to baseline levels of strength. The patient stated that he had adhered 100% to the prescribed PT program. An ASES examination 48 months after surgery on the left side and 33 months after surgery on the right side revealed a significant improvement in function. His active motion on the left was 160° of abduction, 160° of flexion, 45° of external rotation, and internal rotation to T10, and on the right, it was 160° of abduction, 160° of flexion, 45° of external rotation, and internal rotation to T9. Manual muscle testing showed a level of strength of 5/5 in all planes. He was able to transfer, paint, and swim. He reported satisfaction with the results of his surgeries and would recommend the procedure to other SCI patients. Case 2

A 55-year-old, right hand– dominant man with paraplegia had a 3-month history of right shoulder pain on presentation. His pain prevented his ADLs. His preoperative active motion was 155° of abduction, 155° of flexion, 60° of external rotation, and internal rotation to L2. He had a level of strength of 5/5 in the deltoid and 4/5 in the subscapularis (based on the liftoff test), external rotators, and supraspinatus on the right side. Plain radiographic findings were negative. An MRI study revealed a full-thickness tear of the supraspinatus tendon measuring 2.5 cm in the coronal dimension and 3 cm in the axial plane, a partial-thickness tear of the infraspinatus tendon, and partial tearing of

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the proximal biceps tendon. One month after presentation, he underwent arthroscopy including debridement of the torn biceps tendon stump, followed by repair of the rotator cuff tear through a mini-open deltoid-splitting incision with the use of sutures through a bone trough. After surgery, the patient had a full-time attendant to assist in all ADLs. He was back to work part-time 2 weeks after the procedure using an electric wheelchair. He worked with passive motion PT for 6 weeks and began active motion PT at 10 weeks after surgery. Approximately 2 years after surgery on the right shoulder, the patient was seen with a 2-month history of ADL-inhibiting left shoulder pain. His preoperative left shoulder active motion was 140° of abduction, 145° of flexion, 55° of external rotation, and internal rotation to L4. Manual muscle testing revealed levels of strength of 5/5 in the deltoid, 4/5 in the subscapularis, and 3/5 in the supraspinatus on the left side. Radiographic findings were negative. An MRI study revealed a full-thickness tear of the supraspinatus tendon with 2 cm of retraction. Two months after presentation, the patient underwent arthroscopy including debridement of the torn proximal biceps tendon stump, followed by repair of the rotator cuff tear through a mini-open deltoid-splitting incision with the use of stitches through a bone trough. He followed the same rehabilitation protocol with the left shoulder as he had with the right. An ASES examination 48 months after surgery on the right shoulder and 24 months after surgery on the left revealed a significant improvement in function. His active motion on the right side was 170° of abduction, 170° of flexion, 80° of external rotation, and internal rotation to T10, and on the left, it was 160° of abduction, 165° of flexion, 65° of external rotation, and internal rotation to T12. Manual muscle testing showed levels of strength of 5/5 in all planes on the right side and 4⫹/5 in the supraspinatus and 4⫹/5 in the external rotators and subscapularis on the left side. An MRI study was performed 24 months after the left side was repaired, which demonstrated the rotator cuff to be intact. The patient described his left shoulder as good and his right as excellent. He was able to perform all ADLs, swam 3 times per week, and would recommend the surgery to other patients in similar situations. Case 3

A 48-year-old, right hand– dominant male patient who had become a complete T10 paraplegic in 1966 had a 2-month history of right shoulder pain on presentation, 1 year after a right rotator cuff repair that had been performed at another institution with the use of sutures and metallic implants to secure the

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supraspinatus tendon. His pain prevented ADLs. His preoperative active motion on the right side was 150° of abduction, 80° of flexion, 65° of external rotation, and internal rotation to T10, and on the left side, it was 170° of abduction, 140° of flexion, and 80° of external rotation. The patient had levels of strength of 5/5 in the subscapularis, 4/5 in the external rotators, and 3/5 in the supraspinatus on the right side. Radiographic findings were negative. The previous rotator cuff repair was shown to have failed, as an MRI study revealed a massive full-thickness tear of the supraspinatus tendon with 3 cm of retraction. One month after presentation, he underwent surgery for revision of the failed right rotator cuff repair, including arthroscopic removal of the loose hardware from the initial operation, followed by repair of the supraspinatus tendon through a mini-open deltoid-splitting incision with the use of sutures through a bone trough. An anterior labral tear first observed intraoperatively was debrided. After surgery, the patient spent 1 month at an inpatient rehabilitation facility. For the next 4 months, he claimed to have followed the prescribed outpatient PT regimen especially closely because of the previous failed repair. An ASES examination 12 months after surgery on the right side revealed an improvement in function. His active motion on the right was 175° of abduction, 160° of flexion, 55° of external rotation, and internal rotation to T9. The muscle strength was 5/5 in the subscapularis, 4⫹/5 in the external rotators, and 3/5 in the supraspinatus. He had no pain; however, he had difficulty with transfers because of weakness. At that time, an MRI study revealed a recurrent tear of the supraspinatus tendon with 3 cm of retraction. When given the choice to undergo surgery to attempt to restore baseline functionality or to manage the tear nonoperatively, he chose the latter option. Nonetheless, he reported that he was much stronger than before surgery and was now without pain. DISCUSSION Proper function of the upper extremities in the SCI patient is of paramount importance. These patients depend on their upper extremities for mobility, locomotion, and prehension. Shoulder pain has a dramatic impact on the patient’s ability to maintain functional independence. The prevalence of shoulder pain in the paraplegic patient has been reported to be as high as 51%.12 Numerous causative factors have been suggested to account for the large percentage of SCI patients who have shoulder pain. Several studies have cited overuse related to weight-bearing during wheelchair transfers and wheelchair propulsion.1,3,18 Others have noted that pain is more frequently reported with

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increasing age and time from SCI (⬎5 years), possibly related to the overuse theory. These reports suggest that the condition can be prevented by using proper techniques and assistive devices and by learning to recognize the early signs of overuse. Coaches and trainers are also urged to pay close attention to overuse in their athletes. It has also been recommended that balanced strengthening of the muscles acting around the shoulder is critical to independence and the avoidance of injuries and strains.14 With the use of MRI, Escobedo et al5 found that rotator cuff pathology was evident in 71% of symptomatic paraplegic patients compared with 9% of asymptomatic patients. Similarly, Bayley et al1 examined 94 patients and noted a 65% prevalence of rotator cuff tears in symptomatic shoulders in paraplegic patients. These tears were classified as chronic and degenerative in approximately 75% of the patients.1 Integrity of the rotator cuff is of vital importance for shoulder strength. Studies have shown that an isolated tear of the supraspinatus tendon should not affect stability, provided that the transverse force couple (infraspinatus, subscapularis, and teres minor tendons) is intact. With increasing tear size, there is increasing shoulder weakness and decreasing ability to elevate. As a result, function is diminished and patients with multiple tendon tears are more likely to be incapacitated.5,22 Despite the recent reports of debilitating shoulder pain in the SCI patient, there is a paucity of data about the treatment of such a problem. Few studies have focused on the surgical treatment of rotator cuff tears. Perhaps both the extensive postoperative rehabilitation and the immobilization warranted have deterred both the physician and the patient from aggressive surgical repair of the torn rotator cuff. Goldstein et al8 reported poor results in 5 of 6 shoulders in which they had attempted to repair the rotator cuff. Some of the factors that they attributed to the poor results included smoking, decreased baseline passive range of motion, a history that was insidious in onset, atrophy of the supraspinatus and infraspinatus, and superior migration of the humeral head (revealed by radiographic evaluation). Robinson et al18 reported favorable outcomes in 4 shoulders that underwent rotator cuff repairs and subacromial decompression. All had tears localized to the supraspinatus tendon. There was little mention of the long-term follow-up and overall satisfaction. Localization of tears to the supraspinatus is not by chance. Neer11 reported that the supraspinatus tendon is the most tenuous area, as it lies anterior to the acromion when in the anatomic position. Internal rotation causes the tendon to lie more anterior, and external rotation places the tendon lateral to the anterior tip of the acromion. During wheelchair propulsion, Harburn and Spaulding9 noted that the shoulder

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is maintained at approximately 70° of abduction, proximal to the position that places the supraspinatus tendon at the greatest risk of injury.16,18 Increasing injury to the rotator cuff is then seen as a continuum, potentially starting with a single fiber failure of the supraspinatus tendon and potentially propagating to complete avulsions of this and the surrounding cuff tendons.10 All of the patients in our study exhibited a tear in the supraspinatus tendon. Pentland and Tworney14 found that only 10% of SCI patients sought medical attention for shoulder pain and speculated that the patients were fearful of invasive treatment. This hesitancy to seek medical care could result in exacerbation of the injury coupled with chronicity, which would make surgical repair more challenging and perhaps less successful. There is also a general lack of supporting studies on this topic despite the prevalence of shoulder pain in SCI patients. In a review of 130 SCI patients, Dalyan et al4 found that 58.5% (76/130) had upper extremity pain. Of these patients, 63% (48/76) sought medical treatment. This treatment consisted of PT (85%), medication (96%), and massage (88%), with 81% of the PT group, 85% of the medication group, and 88% treated with massage receiving relief. Only 6% of the 48 receiving treatment underwent surgical intervention, and all had good results. Also of interest, just 23% received training for home and wheelchair modification and joint protection. The weight-bearing demands on the SCI patient’s shoulders far surpass the typical demands on the shoulders of able-bodied individuals. Shoulder weakness resulting from a rotator cuff tear can dramatically hinder the SCI patient’s independence and quality of life. Surgical intervention in the SCI patient’s shoulder can restore this independence, but the decision to perform the procedure should not be taken lightly. The patients in this study were given the option of surgical repair early after diagnosis, with a clear understanding of the protective phase that would be required postoperatively and subsequent rehabilitation, both potentially requiring an inpatient stay. All patients in this study used electric wheelchairs and performed only assisted transfers for the first 8 weeks. Independent transfers and manual wheelchair use were permitted after week 10. Perhaps because of the weight-bearing nature of the SCI patient’s shoulder, bilateral rotator cuff tears were present in 2 of 5 patients and revision rotator cuff surgery was required in 2 of 5 patients. We report a favorable outcome for rotator cuff repairs in SCI patients. Pain was reduced, transfers were performed with greater ease, and night pain was diminished in 7 of 8 shoulders. Biceps tendon pain and/or intraoperatively observed biceps tendon pathology was evident in 7 of 8 shoulders (87.5%), with minimal overall loss of function. This high inci-

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dence of concomitant biceps pathology is likely a result of the weight-bearing demands on the SCI patient’s shoulder. However, given our small patient population, we cannot offer any firm conclusions regarding the potential link of rotator cuff and biceps tendon pathology. Postoperative education including home modification, wheelchair modification, and joint protection techniques is important for good longterm results. Also notable, the patients in our study were nonsmokers with acute injuries (7/8), normal radiographic findings, and no fatty degeneration on MRI examination. Multicenter studies with larger numbers are needed to confirm these early findings. REFERENCES

1. Bayley JC, Cochran TP, Sledge CB. The weight bearing shoulder. The impingement syndrome in paraplegics. J Bone Joint Surg Am 1987;69:676-8. 2. Burnham RS, May L, Nelson E, Steadward R, Reid D. Shoulder pain in wheelchair athletes, the role of muscle imbalance. Am J Sports Med 1993;21:238-42. 3. Curtis KA, Drysdale GA, Lanza D, et al. Shoulder pain in wheelchair users with tetraplegia and paraplegia. Arch Phys Med Rehabil 1999;80:453-7. 4. Dalyan M, Cardenas DD, Gerard B. Upper extremity pain after spinal cord injury. Spinal Cord 1999;37:191-5. 5. Escobedo E, Hunter JC, Hollister MC, Patten RM, Goldstein B. MR imaging of rotator cuff tears in individuals with paraplegia. AJR Am J Roentgenol 1997;168:919-23. 6. Geisler WO, Jousse AT, Wynne-Jones M, Breithaupt D. Survival in traumatic spinal cord injury. Paraplegia 1983;21:364-73. 7. Gellman H, Sie I, Waters RL. Late complications of the weight bearing upper extremity in the paraplegic patient. Clin Orthop 1988;233:132-5. 8. Goldstein B, Young J, Escobedo EM. Rotator cuff repairs in individuals with paraplegia. Am J Phys Med Rehabil 1997;76: 316-22. 9. Harburn KL, Spaulding SJ. Muscle activity in the spinal cord injured during wheelchair ambulation. Am J Occup Ther 1986; 40:629-36. 10. Matsen FA III, Arntz FA. Rotator cuff tendon failure. In: Rockwood CA, Matsen FA III, editors. The shoulder. Philadelphia: Saunders; 1990. 647-77. 11. Neer CS II. Anterior acromioplasty for chronic impingement syndrome of the shoulder. J Bone Joint Surg Am 1972;54:41-50. 12. Nichols PJR, Norman PA, Ennis JR. Wheelchair user’s shoulders? Shoulder pain in patients with spinal cord lesions. Scand J Rehabil Med 1979;11:29-32. 13. Pentland WE, Tworney LT. Upper limb function in persons with long term paraplegia and implications for independence: part I. Paraplegia 1994;32:211-8. 14. Pentland WE, Tworney LT. Upper limb function in persons with long term paraplegia and implications for independence: part II. Paraplegia 1994;32:219-24. 15. Powers CM, Newsam CJ, Gronley JK, Fontaine CA, Perry J. Isometric shoulder torque in subjects with spinal cord injury. Arch Phys Med Rehabil 1994;75:761-5. 16. Rathbun JB, Macnab I. The microvascular pattern of the rotator cuff. J Bone Joint Surg Br 1970;52:540-53. 17. Richards RR, Bigliani LU, Gartsman GM, et al. A standardized method for the assessment of shoulder function. J Shoulder Elbow Surg 1994;3:347-52. 18. Robinson MD, Hussey RW, Ha CY. Surgical decompression of impingement in the weightbearing shoulder. Arch Phys Med Rehabil 1993;74:324-7.

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19. Sie I, Waters RL, Adkins RH, Gelmann H. Upper extremity pain in the post rehabilitation spinal cord injured patient. Arch Phys Med Rehabil 1992;73:44-8. 20. Silfverskiold J, Waters RL. Shoulder pain and functional disability in spinal cord injury patients. Clin Orthop 1991;272:141-5. 21. Spinal cord injury: facts and figures at a glance—May, 2001. Spinal Cord Injury Information Network Web site. Available at:

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http://www.spinalcord.uab.edu/show.asp?durki⫽21446. Accessed August 13, 2001. 22. Thompson WO, Debski RE, Boardman ND III, et al. A biomechanical analysis of rotator cuff deficiency in a cadaveric model. Am J Sports Med 1996;24:286-92. 23. Zvijac JE, Seltzer DG. The technique of arthroscopy-assisted rotator cuff repair. Oper Tech Orthop 1993;8:212-24.