Insuffisance du premier rayon

Abstract

First bone ray insufficiency refers to a pressure defect on the first metatarsal head; it should be considered as a syndrome related to several diagnoses, not only at the level of the first ray but also at the level of the second ray, and even of the intermetatarsal spaces. The most frequent cause is an inadequate length of the first bone ray. Diagnosis is sometimes difficult due to multiple clinical presentations, but standard or electronic podometry can confirm the diagnosis by ascertaining a deleterious load transfer to median rays. Routine X-ray allows visualising the metatarsus and the relationships between the metatarsal bones according to their respective length, which is the pathophysiological basis of this affection. After the diagnosis is established and the static disorder is identified, medical instructions are proposed to the patient, such as shoe optimisation, lifestyle measures, rehabilitation, and above all plantar orthesis fitting. In case of treatment failure or inefficacy despite good compliance, surgery may be considered. Depending on the existence or absence of a first ray shift in the foot axis (metatarsus varus), the surgeon will act only on the metatarsus in order to restore harmonious shape, or on the first ray, or on both.