Risk Factors for Shoulder Stiffness After Rotator Cuff Repair: A Systematic Review and Meta-analysis

Shoulder stiffness after rotator cuff repair (RCR) represents a primary determinant of patient-reported quality of life. The implementation of predictive strategies for the early identification of risk factors is critical for mitigating this complication.

To evaluate the incidence of shoulder stiffness after RCR and to identify associated risk factors.

Systematic review and meta-analysis; Level of evidence, 4.

A comprehensive literature search was conducted in PubMed, Embase, Web of Science, and the Cochrane Library from database inception to February 28, 2025. Factors reported in ≥2 studies with extractable data underwent meta-analysis; otherwise, a qualitative synthesis was performed. Sensitivity analyses were executed for risk factors exhibiting substantial heterogeneity or potential reporting bias. Effect sizes for risk factors were calculated using odds ratios (ORs) or mean differences (MDs) with 95% confidence intervals (CIs).

This meta-analysis incorporated 20 studies comprising 34,565 patients undergoing RCR. The pooled incidence of postoperative stiffness was 12.9% (95% CI, 8.5%-18.0%), with significant variations based on diagnostic criteria (15.8% for range of motion vs 2.2% for intervention-based definitions; P < .001) and follow-up duration (18.9% at <6 months vs 9.2% at ≥6 months; P < .05). Overall, 33 potential risk factors for stiffness after RCR were identified, with 11 amenable to meta-analysis. Significant associations emerged for diabetes mellitus (OR, 1.51 [95% CI, 1.07-2.14]), fatty infiltration (OR, 1.58 [95% CI, 1.08-2.31]), concomitant subacromial decompression (OR, 3.26 [95% CI, 1.88-5.65]), and older age (MD, 1.33 [95% CI, 0.39-2.27]) (all P < .05). No statistically significant correlations were observed for sex, body mass index, symptom duration, dyslipidemia, hypothyroidism, tear size, or surgical approach (all P > .05).

This study revealed a pooled incidence of 12.9% for stiffness after RCR, with notable variations observed across diagnostic criteria and follow-up durations. Additionally, older age, diabetes, fatty infiltration, and concomitant subacromial decompression were identified as significant risk factors for postoperative stiffness. Clinicians should prioritize recognizing these risk factors and implementing evidence-based preventive strategies to reduce the incidence of stiffness after RCR.