Physical workload and musculoskeletal disorders among hospital health workers in Tehran, Iran: a cross-sectional...

Health-care workers face considerable physical demands that predispose them to musculoskeletal disorders (MSDs). This study examined and quantified the association between perceived physical workload and region-specific musculoskeletal pain among hospital staff in Tehran, Iran. In this cross-sectional study conducted in 2025 in university-affiliated hospitals in Tehran, 508 clinical personnel completed the Persian Physical Workload Questionnaire (PWQ) and the Extended Nordic Musculoskeletal Questionnaire (NMQ-E). Descriptive statistics summarized the burden and exposures. Generalized Estimating Equations (GEE) models were used to examine the association between physical workload scores and musculoskeletal pain across nine body regions. Robust standard errors were used. Mean total PWQ score was 59.52 (SD = 9.35). Lifetime prevalence was highest for neck (65.9%), low back (49.7%), and upper back (47.5%). Each one-unit increase in PWQ was associated with 1.7% higher odds of reporting regional pain (OR = 1.017; 95% CI 1.007-1.028; p = 0.001). While the per-unit effect is small, cumulative differences are meaningful: a 10-point increase corresponds to a 17% higher odds, and a one-standard-deviation increase (9.35 points) corresponds to a 15.9% higher odds. Among hospital staff in Tehran, higher perceived physical workload appears to be associated with increased likelihood of musculoskeletal pain, particularly in the cervical and lumbar regions. Although the per-unit odds ratios are modest, differences in exposure across the observed range of physical workload may translate into clinically relevant increases in risk. These findings should be interpreted cautiously due to the cross-sectional design, reliance on self-reported measures, and convenience sampling, which preclude causal inference. Interventions such as ergonomic redesign, patient-handling equipment, and targeted training warrant further evaluation in longitudinal or interventional studies.