Arthritis & Rheumatism, Volume 62,
November 2010 Abstract Supplement

Abstracts of the American College of
Rheumatology/Association of Rheumatology Health Professionals
Annual Scientific Meeting
Atlanta, Georgia November 6-11, 2010.

The Effect of Structural Deformities on Typing Styles of Touch Typists with Rheumatoid Arthritis.

Baker2,  Nancy A., Gustafson2,  Norman P., Shin3,  Hyekyoung, Rogers1,  Joan C.

Pittsburgh, PA
University of Pittsburgh, Pittsburgh, PA
University of Pittsburgh


Rheumatoid arthritis (RA) may lead to severe fixed structural deformities of the hand and wrist that may change postures/motions during touch typing. Understanding the mechanism of hand motions during touch typing may provide insight into how people with RA can use their computer safely. This cross-sectional study examined the effect of structural deformities on the postures/motions of the hand/wrist during touch typing. We hypothesized that touch typists with RA with structural deformities would have significantly different typing postures/motions and speeds than those without structural deformities.


A total of 33 subjects with RA were recruited from the University of Pittsburgh Medical Center (UPMC). Subjects were adults with RA, aged from 18 to 65 years, who self-reported being touch typists. Subjects' posture/motions during typing were videotaped and rated for visual structural deformities (VSD) by a certified hand therapist. Typing postures/motions were rated by two trained raters using the Keyboard-Personal Computer Style Instrument (K-PeCS). Typing speed was calculated in words per minute. Based on the presence of any VSD, subjects were divided into two groups: 22 subjects with VSD and 11 subjects without VSD. Chi Square statistics and independent t-test were used to compare the K-PeCS items and typing speed between the two groups.


The subjects were primarily female (88%), a mean age of 56.3 ± 8.8, and white (91%). Touch typists with VSD showed more fixed hand/wrist motions than those without VSD (Figure 1). Significantly more subjects with VSD showed whole hand motions to activate the keys rather than individual finger motions (i.e., no ulna deviation, no MCP hyperextension, straight finger joints, and use of 2 or less fingers). Significantly fewer subjects with VSD also used a wrist support. There was no significant difference for typing speed between the subjects with VSD (25.9 ± 13.0 wpm) and without VSD (27.7 ± 11.4 wpm) (p=.70).

Figure 1. Significantly different postures/motions during touch typing (*p <.05).


Structural deformities can affect the typing styles of touch typists with RA. To compensate for inflexible hand movements, touch typists with VSD showed alternative typing strategies, such as "hunt and peck" style: moving whole hands rather than individual joints, floating the wrists, using fewer fingers, and keeping their fingers straight rather than curved. However these strategies may exacerbate existing problems by putting additional stress on already affected joints. Further evaluation by age should be considered.

Possible suggestions to ensure proper working posture include ergonomic keyboard, moveable wrist support, or redesign of computer workstation.


Funding was provided by the American College of Rheumatology Research and Education Health Professional Investigator Award.

To cite this abstract, please use the following information:
Baker, Nancy A., Gustafson, Norman P., Shin, Hyekyoung, Rogers, Joan C.; The Effect of Structural Deformities on Typing Styles of Touch Typists with Rheumatoid Arthritis. [abstract]. Arthritis Rheum 2010;62 Suppl 10 :2142
DOI: 10.1002/art.29906

Abstract Supplement

Meeting Menu