Associations between biopsychosocial factors and chronic upper limb pain among slaughterhouse workers: cross sectional study

Knowledge of factors associated with chronic pain is necessary for preventive strategies. The present study investigates biopsychosocial differences, with specific focus on rate of force development (RFD) and work ability, between workers with and without chronic upper limb pain. Eighty-two male slaughterhouse workers, 49 with chronic upper limb pain and 33 pain-free controls participated in the study. Maximal muscle strength, RFD, and muscle activity was determined from fast and forceful maximal voluntary contractions for the shoulder and hand. Participants filled out a questionnaire on work ability (work ability index), work disability (Work module of DASH questionnaire), fear avoidance, and self-rated health. Additionally, pressure pain threshold (PPT) was measured in muscles of the arm, shoulder and lower leg. Muscle strength and RFD (determined within time intervals of 30, 50, 100, and 200 ms relative to onset of contraction) was 28% and 58-78% lower, respectively, in workers with chronic pain compared with pain-free controls, and paralleled by reduced muscle activity (all p??0.4). The authors concluded that chronic upper limb pain was paralleled by reduced neuromuscular function of the shoulder and hand along with impaired work ability, work disability and general health. Future studies on chronic pain management at the workplace should carefully consider the biopsychosocial nature of pain when designing and implementing preventive strategies.

Authors: Sundstrup E, Jakobsen MD, Brandt M, Jay K, Aagaard P, Andersen LL. ;Full Source: BMC Musculoskeletal Disorders. 2016 Feb 27;17(1):104. ;