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Arthroscopic Capsular Release for Adhesive Capsulitis

Because adhesive capsulitis of the shoulder, by definition, is due only to a tight and thickened glenohumeral capsule, arthroscopic surgery seems ideal for the treatment of this problem. The capsule is best viewed, and more directly surgically addressed, by an intra-articular approach rather than an extra-articular, open surgical approach. Arthroscopy allows circumferential capsular release as needed, and post operative pain is often much less due to the absence of trans-muscular surgical dissection. An important additional benefit to arthroscopic capsular release is that it can be performed without having to detach and then repair the subscapularis tendon that may be necessary with an open release. This becomes important during postoperative rehabilitation, as there is no need to limit the patient’s abduction or rotation to protect against rupture of this tendon during early post-surgical range of motion.

The risks associated with arthroscopic glenohumeral capsular release include iatrogenic damage to the joint surfaces, excessive soft tissue swelling and axillary nerve injury. The safe performance of this procedure requires sufficient prior experience with shoulder arthroscopy to prevent inadvertent intra-articular injury to the joint surfaces when inserting the arthroscopic cannulae, and an appropriate amount of skill and caution to avoid injury to the labrum and the rotator cuff tendons during debridement. Lack of arthroscopic experience may also result in slower surgical progress, which invites excessive fluid extravisation and soft tissue swelling which can interfere with successful completion of the procedure. These risks, however, diminish as surgeons become more practiced with arthroscopic surgical techniques in general. The axillary nerve, due to its close proximity to the extra-articular surface of the inferior glenohumeral capsule, is at risk for injury during this and any surgical procedure involving the inferior capsule region of the shoulder joint. With open surgical approaches, the nerve can be identified, retracted and protected prior to division of the capsule. During an arthroscopic approach, the axillary nerve most often cannot be seen through the capsule. To avoid inadvertent neural injury, a thorough understanding of its location is mandatory. In a cadaveric study, Zanotti and Kuhn performed an arthroscopic circumferential capsular release using an electrocautery tip approximately 1 cm lateral to the glenoid rim while the arm was in a position of 45 degrees abduction and 20 degrees flexion. Subsequent dissection showed that in all specimens the axillary nerve lay anterior to the inferior edge of the subscapularis muscle at the level of the glenoid rim and it continued laterally and inferiorly under the subscapularis close to the inferior capsule approximately 17 mm lateral to the inferior glenoid rim. These findings indicated that a capsular incision a few millimeters lateral to the glenoid labrum should not place the nerve at risk for injury. The clinical experience of many surgeons performing arthroscopic capsular release has confirmed the safety of this approach. Some variation in the normal course of the nerve might occur, so one must always exercise caution not to penetrate or “plunge” beyond the external capsular border when incising the inferior capsule. Because patients with prior open surgery in the inferior capsular area will have postoperative scarring which may distort and displace this nerve into an abnormal location, capsular release surgery in these patients may be safer if performed with open techniques.

Clinical outcomes after arthroscopic capsular release have been gratifying, with published reports documenting 69% to 94% patient satisfaction. Harryman used this technique on 30 of their most refractory patients with glenohumeral stiffness. The average pre-operative shoulder range of motion was 41% of the uninvolved shoulder. Average postoperative range of motion at one day post surgery was 78% of normal and 93% of normal at final follow up. Pre-operatively only 6% of their patients could sleep on the involved side while postoperatively 73% could do so. In 10% of patients, they observed postoperative recurrence of refractory stiffness. Watson reported that their group of 73 patients experienced diminished pain at an average of 2.24 weeks with the return of motion to within 10% of the uninvolved shoulder after an average of 5.5 weeks postoperative. They noted that many patients, mostly in those operated upon during the proliferative phase of their disease and experiencing significant night pain, developed recurrence of pain at an average 4.5 weeks post-surgery, but these symptoms were adequately treated with massage or corticosteroid injection. With 12 months of postoperative follow up, they reported a recurrence rate of 11%. Ogilvie-Harris observed favorable results using arthroscopic capsular release to treat patients with diabetic adhesive capsulitis. They reported that 76% of these patients had no pain and full range of motion while another 12% had only mild persisting loss of function after arthroscopic release. In the patient group treated by Harryman , approximately 47% of their patients were diabetic and they observed no difference in any outcomes when these patients were compared to the nondiabetic patients. Goldberg also noted no difference in outcome after arthroscopic capsular release in diabetic patients.

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