Effect of four computer keyboards in computer users with upper extremity musculoskeletal disorders

Am J Ind Med. 1999 Jun;35(6):647-61. doi: 10.1002/(sici)1097-0274(199906)35:6<647::aid-ajim12>3.0.co;2-5.


Eighty computer users with musculoskeletal disorders participated in a 6-month, randomized, placebo-controlled trial evaluating the effects of four computer keyboards on clinical findings, pain severity, functional hand status, and comfort. The alternative geometry keyboards tested were: the Apple Adjustable Keyboard [kb1], Comfort Keyboard System [kb2], Microsoft Natural Keyboard [kb3], and placebo. Compared to placebo, kb3 and to a lesser extent kb1 groups demonstrated an improving trend in pain severity and hand function following 6 months of keyboard use. However, there was no corresponding consistent improvement in clinical findings in the alternative geometry keyboard groups compared to the placebo group. Overall, there was a significant correlation between improvement of pain severity and greater satisfaction with the keyboards. These results provide evidence that keyboard users may experience a reduction in hand pain after several months of use of some alternative geometry keyboards.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adult
  • Analysis of Variance
  • Carpal Tunnel Syndrome / rehabilitation*
  • Computer Terminals*
  • Disability Evaluation
  • Equipment Design
  • Ergonomics*
  • Female
  • Humans
  • Linear Models
  • Male
  • Middle Aged
  • Occupational Diseases / rehabilitation*
  • Pain Measurement
  • Statistics, Nonparametric
  • Tendinopathy / rehabilitation*