The reliability of a smartphone goniometer application compared with a traditional goniometer for measuring first metatarsophalangeal joint dorsiflexion.

Background: Adequate sagittal plane motion of the first metatarsalphalangeal joint (1st MTPJ) is important during normal gait and goniometric measurement is commonly used as a diagnostic and outcome assessment tool. We aimed to determine the intra and inter-rater reliability together with the concurrent validity of a universal plastic goniometer (UG) and a smartphone applicationlication (Dr G) for the measurement of dorsiflexion at the 1st MTPJ.

Methods: Measurement of joint position and passive range of motion of the 1st MTPJ dorsiflexion was compared using a UG and DrG goniometer.