First Ray Mobility Increase in Patients With Metatarsalgia

Abstract

The significance and measurement of first metatarsal hypermobility has been difficult to quantify in relation to transfer metatarsalgia. We evaluated the hypothesis that dynamic elevation of the first metatarsal relative to the second metatarsal could be measured with a simple device and would be associated with transfer metatarsalgia. We also assessed intraobserver and interobserver reliability of the simple device. A series of 352 patients were prospectively measured for dynamic metatarsal elevation: 64 patients with transfer metatarsalgia and 288 patients without symptoms. Those with metatarsalgia symptoms had significantly greater first ray mobility (9 mm versus 7 mm; p < 0.0002) and metatarsal elevation (5 mm versus 3 mm; p < 0.0002) than patients without symptoms. In this prospective series, the device was reliable for measuring dynamic first metatarsal elevation at different time points with different examiners. Patients with metatarsalgia had higher dynamic metatarsal elevation compared to patients without metatarsalgia, suggesting a mechanism by which load can be transferred from the first to lesser metatarsals.