Ultrasound changes after rotator cuff repair: is supraspinatus tendon thickness related to pain?

BACKGROUND Little is known about the morphology of healing rotator cuffs after surgical repair. This investigation aimed to determine whether there are changes in tendon thickness, subacromial bursa, anatomical footprint, tendon vascularity, and capsular thickness after rotator cuff repair, and whether supraspinatus tendon thickness correlates with pain. METHODS Fifty-seven patients completed a validated pain questionnaire. Using a standardized protocol, their shoulders were scanned by the same ultrasonographer at 1 week, 6 weeks, 3 months, and 6 months postarthroscopic repair by a single surgeon. The contralateral shoulders, if uninjured, were also scanned. RESULTS Of 57 patients, 4 re-tore their tendons at 6 weeks and 4 retore at 3 months. Sixteen of the remaining 49 patients had intact contralateral supraspinatus tendons. The repaired supraspinatus tendon thickness remained unchanged throughout the 6 months. Compared to week 1, at 6 months, bursal thickness decreased from 1.9 (0.7) mm to 0.7 (0.5) mm (P < .001); anatomical footprint increased from 7.0 (2.0) mm to 9.3 (1.5) mm; tendon vascularity decreased from mild to none (P < .001); posterior capsule thickness decreased from 2.3 (0.8) mm to 1.3 (0.6) mm (P < .001). Frequency and severity of pain and shoulder stiffness decreased (P < .001). There was no correlation between tendon thickness and pain. CONCLUSION After rotator cuff repair, there was an immediate increase in subacromial bursa thickness, tendon vascularity, and posterior glenohumeral capsular thickness. These normalized after 6 months. Tendon thickness was unchanged while footprint contact was comparable with the contralateral tendons. There was no correlation between tendon thickness and pain.