Kinetics of recovery after arthroscopic rotator cuff repair: early motion, delayed strength, and age-related...

Arthroscopic rotator cuff repair (RCR) provides reliable improvements in pain and function, yet the temporal pattern of postoperative recovery remains poorly characterized. In particular, the kinetics of recovery across functional domains and the determinants of early recovery are not well established.

The primary objective of this study was to assess the kinetics of functional recovery following arthroscopic rotator cuff repair. The secondary objectives were (1) to identify factors associated with the speed of recovery and (2) to determine whether a temporal sequence exists between recovery of range of motion and muscle strength.

A retrospective single-center study included 167 consecutive patients who underwent primary arthroscopic repair of full-thickness rotator cuff tears between 2022 and 2023, with a minimum follow-up of 12 months. Clinical evaluation was performed preoperatively and at 1, 3, 6, and 12 months postoperatively, including patient-reported outcome measures (Constant score, ASES, SSV), range of motion (ROM), and muscle strength. Functional recovery was expressed as a percentage of the 12-month value. Near-complete recovery was defined as ≥90% of the final outcome. Univariate and multivariate analyses were performed to identify factors associated with early recovery.

At 3 months, forward flexion, abduction, external rotation, and internal rotation reached 79.2%, 73.9%, 69.5%, and 74.9% of their 12-month values, respectively. At 6 months, these values were 91.0%, 88.2%, 82.5%, and 90.4%. Strength reached 49.2% and 75.8% of its 12-month value at 3 and 6 months, respectively. External rotation recovery was lower than that of forward flexion, abduction, and internal rotation at 3 months (p = 0.018, 0.027, and 0.041), with no differences at 6 months (p = 0.42, 0.37, and 0.48). Strength recovery was lower than that of forward flexion, abduction, and internal rotation at 3 months (p = 0.004, 0.009, and 0.012), but comparable to external rotation (p = 0.18), and to all ROM parameters at 6 months. PROMs reached 74.6% (Constant), 79.5% (ASES), and 77.1% (SSV) at 3 months, and 88.2%, 89.6%, and 88.4% at 6 months, respectively. At 6 months, 59.9%, 62.9%, and 57.5% of patients achieved near-complete recovery for the Constant score, ASES, and SSV, respectively. In multivariate analysis, older age was independently associated with achieving near-complete recovery of the Constant score at 6 months (p = 0.048).

Functional recovery after arthroscopic RCR follows a predictable but non-uniform sequence, characterized by early improvements in ROM and patient-reported outcomes, followed by delayed strength restoration. At 6 months, 59.9%-62.9% of patients achieve near-complete recovery depending on the outcome measure. These findings provide clinically relevant benchmarks for patient counseling and support the need for prolonged rehabilitation strategies focused on strength recovery.

III; retrospective cohort study.