Incubating a Fisherman's Intervention Idea: An Ergonomic Evaluation of Worker Modified Knives Used for Scalloping.

OBJECTIVES

This study aimed to characterize muscular load during real-world commercial scallop shucking in field settings. The study also evaluated the effects of a fisherman-led ergonomic intervention on reducing muscular load and perceived fatigue among professional scallopers during their regular work.

METHODS

A repeated-measures, field-based study was conducted with 20 commercial scallopers in the Northeast U.S. Participants performed scallop shucking using both a standard stock knife and a modified (i.e. taped-handle) knife during typical work shifts, with each condition lasting approximately 50 minutes. Muscle activity in the finger flexor and extensor muscles was recorded using wireless surface electromyography (EMG) and normalized to maximum voluntary contractions (MVCs). Perceived fatigue and tool usability were measured pre- and post-task using the Borg CR-10 scale and 7-point Likert questionnaires, respectively.

RESULTS

Use of modified (taped-handle) knives significantly reduced both median and peak muscle activity in the finger flexor muscles (p < .05, Cohen's d ≈ 0.52-0.54), indicating lowered muscular demands during shucking. Reductions were observed at sustained and peak activity levels that are particularly relevant to work-related musculoskeletal disorder (WMSD) risk. These objective findings were corroborated by subjective reports, with participants indicating lower hand and wrist fatigue and higher ratings for ease of use, comfort, and speed of adaptation when using the modified knives. The majority of participants expressed strong interest in adopting the modified tool for regular use.

CONCLUSION

This study demonstrates that a simple, low-cost, fisherman-driven handle modification can meaningfully reduce musculoskeletal loading and perceived fatigue during commercial scallop shucking without compromising work pace, highlighting the potential of participatory ergonomic interventions in real-world fishing environments.