Mobility of the First Metatarsophalangeal Joint in Diabetic Neuropathy

Dynamic Motion Analysis During Walking

Abstract

Limited joint mobility is a common complication in diabetic neuropathy and is considered a risk factor for plantar foot ulceration. However, in previous studies, joint mobility was measured statically and passively with a goniometer. As most foot injuries occur while the patient is walking, it is both important and practical to evaluate joint mobility during active walking.
Dorsiflexion at the first metatarsophalangeal (MTP) joint is essential during the toe-off phase of walking. We measured the maximum range of dorsiflexion at the first MTP joint during walking in diabetic patients by using a PEAK Video/Computer Motion Measurement System (Peak Perform. Tech, Inc., USA). Forty-eight subjects were studied in three groups: controls (C group, n=16), diabetic patients without neuropathy (D group, n=16), and diabetic patients with neuropathy (DN group, n=16). Motion at the first MTP joint was recorded on video tape by high-speed video cameras set up on both sides while the subject walked on a treadmill at 2.2 and 4.0 km/hr. The maximum range of dorsiflexion of the first MTP joint in the toe-off phase was calculated by the computer.
This gait analysis study yielded some new findings not revealed by the static examination with the goniometer. In most cases, there was a difference between the left and right foot in the maximum range of dorsiflexion during walking. Data for the left and right foot were analyzed separately. The maximum range of dorsiflexion at the first MTP joint was significantly lower in the DN group than in the C group or D group at both speeds. Limitation of dorsiflexion at the first MTP joint in the DN group, which was more marked in the left foot, can critically alter the distribution of plantar pressure, and increased plantar pressure in the metatarsal heads or the great toe may lead to plantar ulceration.