A cross-sectional observational study comparing individuals with a symptomatic full-thickness rotator cuff tear with age-matched controls.

BACKGROUND: A full-thickness rotator cuff tear (FTRCT) is defined as a complete tear of one of the four rotator cuff muscle tendons (supraspinatus, infraspinatus, subscapularis or teres minor). This condition can lead to pain and reduced function. However, not all FTRCT are symptomatic. A better understanding of the characteristics that lead some individuals with FTRCT to experience pain is fundamental to improve strategies used to manage this condition. This level II descriptive study aimed to explore potential sociodemographic, anatomical, psychosocial, pain sensitivity, biomechanical and neuromuscular variables that may differ between individuals with symptomatic FTRCT and age-matched individuals with asymptomatic shoulders.

METHODS: In this cross-sectional observational study, adults aged 50 to 80 years of age, either with symptomatic FTRCT or no shoulder pain, were recruited via convenience sampling. Participants filled out questionnaires on sociodemographic and psychosocial variables. Then, various tests were performed, including pain pressure threshold, shoulder range of motion, shoulder muscle strength, shoulder ultrasound and radiologic examination, and sensorimotor functions testing. Each variable was compared between groups using univariate analyses (independent t -tests, Mann-Whitney U tests, exact probability Fisher tests). Significance was set at 0.05.

RESULTS: FTRCT (n = 30) and Control (n = 30) groups were comparable in terms of sex, age, and number of comorbidities. The symptomatic FTRCT group showed a higher proportion of smokers ( P  = .026) and more participants indicated consuming alcohol or drugs more than they meant to ( P  = .010). The FTRCT group had a significantly higher prevalence of glenohumeral osteophytes (48% vs. 17%; P  = .012). Participants in the FTRCT group were significantly more stressed ( P  = .04), anxious ( P  = .003) and depressed ( P  = .002). The FTRCT group also showed significantly higher levels of pain catastrophisation ( P  < .001) and sleep disturbance ( P  < .001). The FTRCT group showed significantly lower range of motion for flexion ( P  < .001), and external rotation at 0° ( P  < .001) and 90° ( P  < .001) of abduction. Isometric strength in both abduction and external rotation were weaker ( P  = .005) for the FTRCT group.

CONCLUSION: Sociodemographic, anatomical, psychosocial and biomechanical variables showed statistically significant differences between the FTRCT and Control groups.