Longitudinal analysis of rotator cuff repair: joint kinematics and clinical outcomes

TL;DR

This study tracks shoulder movement and recovery in patients after rotator cuff surgery over two years, finding improved strength and function but some joint changes.

Contribution

The study provides longitudinal insights into joint kinematics and clinical outcomes after rotator cuff repair, revealing subtle biomechanical changes and healing patterns.

Findings

Surgical rotator cuff repair improved pain and function within the first 3 months.

Shoulder strength significantly increased at 12 and 24 months post-surgery.

Subtle changes in joint motion occurred, with a superior shift in the center of contact on the glenoid over time.

Abstract

Rotator cuff repair is a common surgical procedure, but postoperative outcomes can be highly variable, and postoperative repair tissue healing remains a significant clinical challenge. Furthermore, the biomechanical effects of rotator cuff repair are not fully understood.

Twenty-two participants scheduled for arthroscopic rotator cuff repair were evaluated preoperatively and at 3, 12, and 24 months postsurgery. The following data were recorded at each time point: glenohumeral and scapulothoracic kinematics, shoulder strength, and patient-reported measures of pain and function. Postoperative repair integrity was assessed via magnetic resonance imaging at 3 months and 24 months postsurgery.

At 3 months postsurgery, 5 of 20 patients were identified as having a recurrent tear. An additional 4 patients had a recurrent tear at 24 months postsurgery. The center of contact of the humerus on the glenoid gradually shifted superiorly on the glenoid during the 24 month follow-up period (P < .01). There were subtle changes in scapulothoracic upward rotation at 3 months postsurgery compared to presurgery (P ≤ .01), but these differences did not persist at 12 or 24 months postsurgery. Compared to presurgery, there were significant increases in flexion and internal rotation strength at 12 months postsurgery (P < .01) and significant increases in flexion, abduction, external rotation, and internal rotation strength at 24 months postsurgery (P < .01). Patient-reported measures of pain and function improved significantly over the 24 month follow-up period (P < .01).

Surgical rotator cuff repair was associated with decreased pain and improved subjective assessments of function within the first 3 months after surgery, and increased shoulder strength over 12- 24 months postsurgery. The study also found subtle changes over time in glenohumeral joint and scapulothoracic motion.

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