Effects of obesity on post-surgical recovery and functional outcomes in rotator cuff tear repair

Background Rotator cuff tears (RCTs) are a common cause of shoulder pain and can severely affect patients' ability to perform daily activities. Comorbidities, such as obesity, are known to influence the outcomes of RCT repair, particularly in the context of arthroscopic surgery. However, the effect of obesity on postoperative outcomes following RCT repair has not been sufficiently explored, especially in patients undergoing minimally invasive procedures. This study aims to evaluate the impact of obesity on postoperative pain, range of motion, and functional recovery after arthroscopic rotator cuff repair. Methods This retrospective cohort study included 50 patients who underwent arthroscopic RCT repair between January 1, 2022, and January 1, 2025. All patients were followed for a minimum of two years postoperatively. Data collected included factors such as fatty infiltration (Goutallier grade), tendon retraction (Patte grade), obesity (BMI ≥ 30), education level, and smoking status. The primary outcomes assessed were postoperative pain (Visual Analog Scale, VAS), range of motion (active forward flexion and external rotation), UCLA Shoulder Score, and ASES Score. Results The average age of the study participants was 59.9 ± 7.4 years, with 28% of patients being female. A total of 42 patients (84%) had a full-thickness rotator cuff tear. The median time from diagnosis to surgery was 22.5 months (IQR: 17.3–29.8 months), with a median follow-up duration of 30.2 months (IQR: 26.3–34.1 months). Eighteen patients (36%) were classified as obese (BMI ≥ 30). Obese patients demonstrated a trend toward higher postoperative pain (VAS: 4.8 ± 2.8 vs. 4.0 ± 3.2, p = 0.076), and showed significantly reduced active forward flexion (130.5° ± 48.4° vs. 137.6° ± 52.7°, p = 0.035) and external rotation (40.3° ± 17.4° vs. 48.4° ± 19.5°, p = 0.024) compared to non-obese patients. BMI was negatively correlated with improvements in both forward flexion and abduction following surgery. Conclusion This study found that obesity was significantly associated with reduced active forward flexion ( p = 0.035) and external rotation ( p = 0.024) following arthroscopic rotator cuff repair, and demonstrated a trend toward higher postoperative pain levels ( p = 0.076) that did not reach conventional statistical significance. Functional recovery, as assessed by UCLA and ASES scores, showed a consistent directional trend toward poorer outcomes in obese patients; however, these differences were not statistically significant ( p = 0.196 and p = 0.322, respectively), and should be interpreted with caution given the limited sample size. These findings highlight obesity as a potential risk factor for reduced range of motion recovery following rotator cuff repair, while acknowledging that its impact on broader functional outcomes remains to be confirmed in larger prospective studies. Tailored perioperative and rehabilitation strategies targeting obese patients may help optimize postoperative recovery, though further evidence is needed to guide specific clinical recommendations.