We report seven cases of traumatic dislocation of the great toe, detailing the anatomy, the mechanism of injury and the radiographic diagnosis. We propose an additional classification based on three hereto unreported cases.

Between october 1994 and october 1997, we treated seven patients with traumatic dislocation of the first metatarso-phalangeal joint of the great toe. There were six men and one woman, mean age 35 years (range 24 - 44 years). Dislocation was caused by motor vehicle accidents in four cases and by falls in three. Diagnosis was made on anteroposterior, lateral and medial oblique radiographs. According to Jahss' classification, there was one type I and three type IIB dislocations. There was also one open lateral dislocation and two dorsomedial dislocations. Only these dorsomedial dislocations required open reduction, done via a dorsal approach. Mean follow-up was 17.5 months (range 9 - 24 months) in six cases. One patient was lost to follow-up. The outcome was good in six cases and poor in one (dorsomedial dislocation).

Dislocation of the first metatarso-phalangeal joint of the great toe is an uncommon injury. In 1980, Jahss reported two cases and reviewed three others described in the literature. He proposed three types of dislocation based on the feasibility of closed reduction (type I, II and IIB). In 1991, Copeland and Kanat reported a unique case in which there was an association of IIA and IIB lesions. They proposed an addition to the classification (type IIC). In 1994, Garcia Mata et al. reported another case which had not been described by Jahss and proposed another addition. All dislocations reported to date have been sagittal dislocations. Pathological alteration of the collateral ligaments has not been previously reported. In our experience, we have seen one case of open lateral dislocation due, at surgical exploration, to medial ligament rupture and two cases of dorsomedial dislocation due, at surgical exploration, to lateral ligament rupture.

We propose another additional classification with pure lateral dislocation (type III) and dorso-lateral dislocation (type IL or IIL+), which are related to the formerly described variants.

La luxation traumatique métatarso-phalangienne du gros orteil est peu commune. Rares sont les travaux qui lui ont été consacrés dans la littérature, et tous concernent des luxations sagittales. Le problème essentiel est de déduire d'une analyse radiologique correcte, le type de lésion anatomopathologique, afin de choisir une méthode de réduction adaptée : orthopédique ou chirurgicale. La classification de Jahss modifiée reste la base de toute discussion thérapeutique.

Nous rapportons l'analyse rétrospective de sept cas colligés, dont quatre luxations dorsales s'inscrivant parfaitement dans le cadre de la classification précitée, et trois luxations latérales ne correspondant à aucune des variétés connues jusque là. La réduction a été orthopédique cinq fois, chirurgicale chez deux patients et nous avons opté, alors, pour une voie d'abord dorsale. Le résultat a été bon six fois et mauvais dans un cas (luxation dorso-médiale). Notre série confirme les données de la classification de Jahss et des modifications qui lui ont été apportées.

A la lumière d'une revue de la littérature récente, nous mettons le point sur les aspects radiologiques anatomopathologiques et thérapeutiques de cette affection et nous discutons la classification de Jahss et les compléments qui lui ont été annexés. Nous proposons un autre complément de cette classification pour les luxations latérales, que nous rapportons pour la première fois.