Vol. 40 No. 3, May/June 2003
Pages 235 — 240
Assessment of an electronic goniometer designed to measure equinus contractureMathieu Assal, MD; Jane B. Shofer, MS; Eric Rohr, MS; Robert Price, MS; Joseph Czerniecki, MD;
Bruce J. Sangeorzan, MD
Rehabilitation Research and Development, Center of Excellence in Limb Loss Prevention and Prosthetic Engineering, Seattle VA Medical Center, WA
Abstract — To achieve more objective and repeatable measurements of equinus contracture, we developed the equinometer, a device that allows the measurement of ankle range of motion under controlled torque conditions. This study assessed its accuracy across different subjects and examiners. Two examiners used the equinometer to measure the angle of ankle dorsiflexion at 15 N·m torque on five subjects. Accounting for variation in measurements because of subjects, examiners, and placement of device, we used linear mixed-effects models. Accounting for the variation because of subject, different placements of the equinometer within each subject and the adjustment for the effects of examiner and trial sequence, the standard deviation was 0.94°, 95% confidence interval (0.79°, 1.13°). An upper standard deviation of 1.36° is felt to be acceptable for clinical investigation.
Key words: ankle, equinus, goniometer accuracy.