Relationship Between Magnetic Resonance Imaging-based Knee Cartilage Loss and Work-related Physical Workload in Farmers and Fishers

This study examined the relationship between work-related physical workload and knee cartilage loss using magnetic resonance imaging (MRI) among farmers and fishers in Korea. Bilateral knee MRI and questionnaire data from 545 farmers and 204 fishers aged 40–79 years were analyzed. Cartilage damage was evaluated using the MRI Osteoarthritis Knee Score (MOAKS). Mean cartilage loss scores were compared by sex, age, and BMI. ANCOVA was used to assess associations of cumulative squatting (CSWT, hours) and lifting work time (CLWT, hours) with cartilage loss, adjusting for age and BMI, and stratified by sex. Age was the most significant factor associated with cartilage loss, whereas BMI was not. In women, CSWT was significantly associated with medial cartilage loss in the tibiofemoral joint after adjusting for age and BMI (right: p = 0.036; left: p = 0.021). CLWT was significantly associated with cartilage loss in the right patellofemoral joint (right: p = 0.005; left: p = 0.051). In men, CLWT showed a significant association only in the right medial tibiofemoral joint (p = 0.046). Among Korean farmers and fishers, cumulative squatting and lifting workloads were associated with knee cartilage damage in a compartment- and sex-specific manner.