Finger Tendon Travel Associated with Sequential Trigger Nail Gun Use

Area of Science:

• Occupational Health
• Biomechanics
• Ergonomics

Background:

• Pneumatic nail guns have sequential or contact triggers; sequential triggers are safer against traumatic injuries.
• Sequential triggers require repeated finger motion, raising concerns about cumulative trauma injuries and productivity.
• This study investigates the biomechanical risks associated with sequential trigger nail gun use in wood framing.

Purpose of the Study:

• To develop a method for predicting cumulative finger flexor tendon travel from sequential trigger nail gun use.
• To correlate finger joint kinematics with tendon travel during trigger actuation.
• To assess potential cumulative trauma injury risks based on productivity standards in wood-frame construction.

Main Methods:

• Measured finger motions of six users using electrogoniometer gloves during simulated wall building and flat nailing tasks.
• Calculated cumulative finger flexor tendon travel based on ensemble average kinematics per nail fired.
• Integrated kinematic data with construction industry productivity standards.

Main Results:

• Proximal interphalangeal and distal interphalangeal joint motion were the primary contributors to finger flexor tendon travel.
• Slightly greater tendon travel was observed for wall-building tasks compared to flat nailing.
• Estimated cumulative tendon travel for a high-production workday (1700 trigger presses) is less than 60 m/day per worker.

Conclusions:

• Finger tendon travel exposure from sequential trigger nail gun use may be below established high risk levels for musculoskeletal disorders.
• The findings suggest sequential triggers may offer a favorable risk profile for cumulative trauma injuries in wood framing.
• Further research could refine exposure assessments and inform ergonomic guidelines for nail gun operation.