Relationship between Preoperative Central Sensitization and Postoperative Outcome after Arthroscopic Rotator Cuff Repair - Longitudinal Outcomes Over 2 Postoperative Years

Background: Whether preoperative central sensitization (CS) affects postoperative outcomes after arthroscopic rotator cuff repair (ARCR) remains unclear.This study aimed to evaluate the potential association between preoperative CS and postoperative pain and function for 2 years in patients who underwent ARCR for small-to-medium rotator cuff tears.Methods: Sixty patients with small-to-medium full-thickness rotator cuff tears who underwent ARCR and were followed up for 24 months postoperatively were enrolled.The presence or absence of CS was evaluated using the Japanese version of the Central Sensitization Inventory (short form).Patients were divided into two groups according to the presence or absence of CS, with scores 10 defined as CS.Baseline demographic and radiologic factors (e.g., smoking status, diabetes mellitus, occupation, tear size, and fatty infiltration) were recorded and compared between groups.Postoperative outcomes, including pain (numerical rating scale [NRS]), shoulder range of motion [ROM], muscle strength, and clinical scores [Constant, ASES], were assessed at 3, 6, 12, 18, and 24 months.Rotator cuff integrity was evaluated by MRI at 3, 6, 12, and 24 months postoperatively.Results: CS was present in 45% of patients.There were no significant differences in baseline demographic, clinical, or radiologic factors, as well as in preoperative shoulder joint range of motion, strength, or pain between the groups with and without CS.Patients with CS exhibited significantly less improvement in pain on motion, abduction strength, and clinical scores at multiple time points up to 18 months; by 24 months, however, these differences had diminished.