Reliability and usefulness of the novel ankle plantar flexion strength test

Abstract

The purpose of this study was to verify the reliability and the usefulness of a novel ankle plantar flexion strength test (Plantar flexion break test ; PFBT). 192 healthy volunteers were enrolled. All subjects were measured the ankle range of motion (dorsiflexion / plantar flexion), PFBT, and numbers of heel rising. The result of PFBT (positive / negative) was determined by ankle joint stability when maximum resistance was applied downward to calcaneus during maximum ankle joint plantar flexion in single leg standing position. The PFBT-positive group was significantly lower dorsiflexion range of motion and fewer numbers of heel rising than the PFBT-negative group (p<0.01). Although the reliability within the examiner of PFBT was almost perfect (κ=0.92), the reliability between examiners was fair (κ=0.37). PFBT is simpler than manual muscle test, but further verification is necessary due to the possibility of evaluating different muscle functions.