Factors affecting the risk of developing lower back musculoskeletal disorders (MSDs) in experienced and inexperienced rodworkers.

Injury and dropout rates during rodwork training appear to reflect difficulties encountered by apprentices adapting to increased physical demands of tying on slab, one of the rodworking tasks with the highest injury risk. Because experience influences work strategies, and consequently the risk of developing musculoskeletal disorders (MSDs), this study aimed to identify differences in work practices associated with tying rebar on slab, potentially relevant to back MSD development, in experienced and inexperienced rodworkers. Fourteen male rodworkers were recruited from either experienced (>2 years experience post apprenticeship), or inexperienced (<6 months experience) groups. Both tied an area with rebar laid on the ground. Trunk flexion/extension angles were measured. L4/L5 moments were estimated from T9 Erector Spinae EMG. Experienced workers were found to spend longer periods of time in trunk flexed postures, with lower peak L4/L5 moments. Our findings revealed practices associated with each group might have different implications on back health.