Protective Brace to Prevent Hand and Arm Injuries

When people use hand-held power tools, their hands and arms vibrate along with the tool they are holding. People who frequently use hand-held power tools may develop injuries related to this vibration. This study will evaluate a protective brace designed to prevent vibration-related hand and arms injuries.

Workers who use hand-held power tools absorb significant vibration energy in their arms and hands and may develop musculoskeletal disorders (MSDs) such as carpal tunnel syndrome and hand-arm vibration syndrome. Protective braces may be worn to decrease the incidence of occupational MSDs. The National Institute for Occupational Safety and Health has identified key attributes for protective braces; these attributes include vibration damping, comfort, non-interference with worker dexterity, and maintenance of safe hand temperature. Most currently available braces do not adequately address these NIOSH requirements. This study will evaluate the efficacy of a brace with piezoelectric damping material. Participants in the study will be fitted with a brace on each hand. One brace will have piezoelectric damping material and the other will be a currently available, off-the-shelf commercial brace. Hand-held joysticks and handles mounted to a vibration shaker table will be used to simulate power tool use. Participants will undergo a series of tests designed to measure hand acceleration and vibration while grasping the study joysticks and handles. The tests will take approximately 30 minutes.

Inclusion Criteria: Normal hand anatomy and full range of motion Exclusion Criteria: History of significant hand or wrist arthritis Open wounds Prior hand or wrist surgery Neuropathies Skin hypersensitivity Contact dermatitis Reflex sympathetic dystrophy