Shoulder joint position sense after thermal, open, and arthroscopic capsulorrhaphy for recurrent anterior instability

Identifying the optimal surgical treatment for recurrent, anterior glenohumeral instability remains a challenge. Our purpose was to compare shoulder joint position sense among open, arthroscopic, and thermal capsulorrhaphy patients after repair of recurrent anterior instability and to compare these patients to healthy, control subjects. Sixty-seven adults (45 post-surgical patients, 22 controls) volunteered to participate in the study. We evaluated both the surgically repaired and contralateral shoulders of 45 capsulorrhaphy patients (28 men, 17 women) and compared their results with the normal bilateral shoulders of 22 age-matched controls (11 men, 11 women). Accuracy of joint position sense was quantified via passive reproduction of target positions set at 60% and 90% of each subject's maximum passive external rotation (ER_max). We observed no significant differences in joint position sense between the repaired shoulders and the contralateral normal shoulders of all groups of capsulorrhaphy patients. Open and thermal capsulorrhaphy patients demonstrated significantly better (P ≤ .05) repaired-limb joint position sense (5.4° ± 3.3° and 5.6° ± 3.3°, respectively) than arthroscopic patients (9.2° ± 3.7°) and control subjects (8.1° ± 4.0°). These results indicate that joint position sense was similar in the repaired shoulders and uninjured shoulders of each group of capsulorrhaphy patients. The mechanism responsible for heightened position sense in open and thermal capsulorrhaphy patients is unknown, but may result from capsular retensioning and muscular scarring. The long-term implications of this outcome deserve further attention.