Multiple Injections and Injections ≤6 Month Injections Before Rotator Cuff Repair May Increase the Risk of Retear: A Propensity Score-Matched Study.

Abstract

Background: The role of preoperative corticosteroid injections (CSIs) in rotator cuff repair (RCR) outcomes is controversial, with mixed evidence regarding their effect on tendon healing and postoperative recovery.

Purpose: To control for potential variables that may affect tendon healing and to explore the effect of CSIs on tendon healing and the difference in the effect of injection frequency and time interval on outcomes.

Study design: Cohort study; Level of evidence, 3.

Methods: This retrospective cohort study included 365 patients who underwent arthroscopic RCR between February 2021 and June 2023. Patients were categorized into CSI group (CSI group; n = 113) having a history of injections ≤1 year before surgery and control group (n = 252, 1 patient with bilateral shoulder involvement) without preoperative injections. Propensity score matching (PSM) was employed to reduce the effect of confounding variables, including age, body mass index, tear size, and biceps pathology, resulting in 113 matched pairs. Outcomes, including pain, shoulder function (Constant-Murley Score, Oxford Shoulder Score) were assessed at 3, 6, and 12 months postoperatively. Tendon integrity was evaluated using magnetic resonance imaging (MRI) ≥6 months postoperatively.

Results: After PSM, baseline characteristics were balanced between the groups. At 3 months postoperatively, the CSI group exhibited significantly reduced active abduction and external rotation compared with the control group. Pain at night (visual analog scale, VAS) was also higher in the CSI group than the control group at 3 months (mean value 2.97 vs 2.31; P = .03). However, no significant differences in patient-reported outcome measures (PROMs) were observed between the 2 groups at any time point. MRI assessments of Sugaya grade at ≥6 months postoperatively revealed a higher retear rate in the CSI group compared with control (23.9% vs 8.8%; P = .02). Subgroup analysis indicated that patients who received 2 injections (OR, 3.25; 95% CI, 1.06-10.16; P = .04) or ≥ 3 injections (OR, 5.71; 95% CI, 1.87-18.28; P < .001) had a significantly higher risk of retear compared with the control group. Additionally, patients who received CSI between 3 and 6 months and <3 months before surgery also showed a significantly increased risk of retear compared with the control group (OR, 5.80; 95% CI, 2.07-17.40; P < .001 and OR, 7.25; 95% CI, 1.77-29.65; P = .01, respectively). Cross-effect analysis revealed that receiving ≥ 2 injections within ≤ 6 months before surgery was significantly associated with a higher postoperative retear risk (OR, 7.30; 95% CI, 2.83-20.76; P < .001).

Conclusion: Preoperative CSIs, particularly when administered multiple times and within 6 months before surgery, are associated with a higher risk of retear after RCR. However, there is limited difference in range of motion and PROMs between the 2 groups.