Prevalence of Musculoskeletal Complaints in Underserved Populations Attending a Student-Run Free Clinic in Puerto Rico: A Cross-Sectional Analysis

Background: Musculoskeletal (MSK) disorders are a leading cause of disability worldwide and disproportionately affect individuals facing socioeconomic hardship. In Puerto Rico, recent social and economic disruptions have intensified health inequities, yet data on MSK burden in underserved populations remain limited. Student-run free clinics (SRFCs) provide a unique setting to characterize MSK health in these populations. This study aimed to determine the prevalence of musculoskeletal complaints and functional limitations among adults attending a student-run free clinic in Puerto Rico and to evaluate associated sociodemographic, occupational, and chronic disease-related factors. Methods: We conducted a cross-sectional study among adults attending an SRFC in Old San Juan between February and December 2025. Participants completed a 30-item MSK Function Questionnaire assessing pain, functional limitations, strength, activity modification, and sociodemographic and health-related factors. Data were analyzed descriptively, and subgroup comparisons were performed using Fisher’s exact test. Results: Sixty-two participants were included, most of whom were older, unemployed, and experiencing housing instability. Overall, 77.4% reported at least one MSK limitation. Lower extremity and spine-related symptoms were most common, with frequent reports of pain, functional difficulty, and activity modification. MSK limitations were significantly more prevalent among unemployed individuals and those with chronic medical conditions, particularly diabetes and cardiovascular disease. Multivariable logistic regression analysis demonstrated that chronic conditions and unemployment remained associated with MSK limitations after adjustment. Conclusions: MSK pain and functional impairment were common among underserved patients attending an SRFC in Puerto Rico and were associated with chronic disease burden and unemployment. Given the small sample size, locally developed questionnaire, and cross-sectional design, these findings should be interpreted as preliminary and hypothesis-generating. The relationship between unemployment and MSK impairment should be interpreted as associative and potentially bidirectional.