• Shurong Zhang, Hong Li, Hongyue Tao, Hongyun Li, Samson Cho, Yinghui Hua, Jiwu Chen, Shiyi Chen, and Yunxia Li.
• Department of Sports Medicine, Huashan Hospital, Fudan University, No. 12, Wulumuqi Zhong Road, Shanghai 200040, China.
• Am J Sports Med. 2013 Aug 1;41(8):1885-92.

BackgroundPostoperative passive motion is the most widely accepted rehabilitation protocol after rotator cuff repair; however, a rotator cuff retear remains a frequent surgical complication. Clinical outcomes indicate that early passive motion is harmless to rotator cuff healing, but no laboratory evidence supports this proposition.Hypotheses(1) Immediate postoperative immobilization improves rotator cuff healing in rabbits. (2) Early passive motion after short-term immobilization does not harm rotator cuff healing in rabbits.Study DesignControlled laboratory study.MethodsAn injury to the supraspinatus tendon was created and repaired in 90 New Zealand White rabbits, after which they were randomly separated into 3 groups: (1) nonimmobilization (NI; n = 30), (2) continuous immobilization (IM; n = 30), and (3) immobilization with early passive motion (IP; n = 30). At 3, 6, and 12 weeks postoperatively, 5 rabbits from each group were sacrificed for histological evaluation, biomechanical testing, and magnetic resonance imaging.ResultsThe histological study demonstrated better postoperative healing in the IM and IP groups, with clusters of chondrocytes accumulated at the tendon-bone junction. Magnetic resonance imaging illustrated that the tendon-bone junction was intact in the IM and IP groups. The magnetic resonance quantification analysis showed that the signal-to-noise quotient (SNQ) of the NI group was not significantly higher than that of the immobilization groups at 3 weeks (P = .232) or 6 weeks (P = .117), but it was significantly different at 12 weeks (NI vs IM, P = .006; NI vs IP, P = .009). At 12 weeks, the failure load was significantly higher in the IM and IP groups than in the NI group (NI vs IM, P = .002; NI vs IP, P = .002), but no difference was found between the IM and IP groups (P = .599).ConclusionImmediate postoperative immobilization led to better tendon-bone healing than immediate postoperative mobilization, and under immobilization, early passive motion was harmless to tendon-bone healing in this study.Clinical RelevanceThe results have an implication in supporting the rehabilitation protocol of early passive motion after rotator cuff repair.

27 keywords...

hide…