Agricultural work and chronic musculoskeletal pain among Latino farm workers: the MICASA study

Agriculture poses varied dangers to hired farm workers in the U.S., but little information exists on occupational risks for chronic musculoskeletal pain. We examined common work positions, such as kneeling, carrying heavy loads, and repetitive motion that may increase the risk for chronic musculoskeletal pain.

MICASA is a population-based study of occupational exposures and health in hired farm workers in California. This analysis includes 759 participants, 18-55 years old, engaged in farm work and residing in Mendota, CA. Chronic pain was defined as pain lasting 6 weeks or longer at specific body sites (back, knee, hip, etc.) over the entire farm work career.

Mean age was 37.9 years. Sixty-five percent participants were born in Mexico, 27.7% were born in El Salvador, and 4.2% were U.S-born. Chronic pain was associated with older age and female sex. After adjustment for age, years working in agriculture, and smoking, stooping/bending >30 hr/week among both men (OR = 2.49, 95% CI: 1.03-5.99) and women (OR = 2.15, 95% CI: 1.04-4.46) was associated with chronic hip pain. Driving tractors or other heavy farm equipment >60 hr/week was associated with increased odds of chronic hip pain (OR = 2.16, 95% CI: 1.02-4.54) among men. We also observed significant associations with kneeling or crawling >35 hr/week among women for both chronic back pain (OR = 2.96, 95% CI: 1.27-6.93) and knee pain (OR = 3.02, 95% CI: 1.07-8.50), respectively.

Chronic musculoskeletal pain is prevalent among farm workers and is associated with common work positions. Further research should focus on developing preventive interventions for tasks associated with increased pain risk. These interventions should be targeted to specific types of agricultural tasks.