The Effect of Alternative Keyboards on Discomfort and Typing Kinematics

Awkward postures during computer keyboard use have been hypothesized to be one cause of musculoskeletal pain/discomfort as well as musculoskeletal disorders of the upper extremity (MSD-UE). Alternative computer keyboards purport to reduce musculoskeletal pain/discomfort and have been shown to change aspects of keyboard users' kinematics under laboratory conditions. However, research that has examined the effectiveness of alternative keyboards in reducing musculoskeletal pain/discomfort in the workplace is equivocal, and no study has examined the association between postures and musculoskeletal pain. The Aims of this 3-year prospective double cross-over trial are: 1) To examine the effectiveness of an alternative keyboard in reducing reports of pain over 6-months; 2) To examine the neutrality and stability of postures during keyboard use; and 3) To identify which postures are associated with lower levels of musculoskeletal pain. Seventy-five computer users will be randomly assigned to one of two keyboard use orders: Group 1 - AB (standard keyboard, alternative keyboard); Group 2 - BA (alternative keyboard, standard keyboard). All subjects will use their assigned keyboards for 6-months before switching to the next keyboard. Every week, subjects will report their musculoskeletal pain levels. Just prior to and just after each 6-month intervention subjects' kinematics performances on the keyboards will be recorded at the worksite using the Keyboard - Personal Computing Style (K-PeCS) instrument and in a laboratory setting using 3-dimensional motion capture technology.

Aim 1: To examine the effectiveness of an alternative keyboard in reducing pain over 6-months.

Hypothesis 1 (H-1) - At six months subjects using an alternative keyboard will have significantly lower musculoskeletal pain levels than when using a standard keyboard.

Aim 2: To examine the neutrality and stability of postures during keyboard use.

Hypothesis 3 (H-2) - Subjects using an alternative keyboard will have significantly more neutral postures than when using a standard keyboard at baseline and at 6 months Hypothesis 3 (H-3) - Subjects 6-months keyboarding postures will remain equivalent to the keyboarding postures documented at baseline.