La correction chirurgicale de certaines déformations sévères du médio-pied de l'enfant peut être difficile. La résection de l'os naviculaire, associée à d'autres gestes chirurgicaux permet de traiter certaines de ces déformations. Le but de ce travail était de codifier les indications de naviculectomie, à la lumière d'une série rétrospective de 15 pieds (13 enfants) opérés entre 1980 et 2003. Nous avons classé les déformations en deux groupes : les pieds avec une colonne médiale plus longue que la colonne latérale (pieds planus valgus avec abductus sévère de l'avant pied et pieds convexes déjà opérés avec déformation résiduelle) et les pieds avec subluxation ou luxation de l'os naviculaire et deux colonnes de même longueur (pieds varus équins neurologiques et pieds bots varus équins déjà opérés avec creux résiduel). Les résultats cliniques et radiographiques ont été évalués de façon rétrospective, au recul moyen de 2 ans et 5 mois. La résection de l'os naviculaire a permis une correction satisfaisante des déformations cliniques et radiographiques. La naviculectomie, intégrée dans une chirurgie complète, permet donc dans certaines indications précises d'obtenir une correction de déformations sévères du médio-pied de l'enfant.

The navicular bone lies at the apex of the deformity in severe talipes planovalgus with forefoot abductus, in the residual cavus of congenital talipes equinovarus, in certain cases of congenital convexity, and in certain types of neurological equinovarus. Resection of the navicular bone can be proposed to correct certain deformities.

This series included 15 feet operated on in 13 children from 1980 to 2003. The deformity to be corrected was a residual cavus after surgery for congenital talipes equinovarus (five feet), plantar and medial dislocation of the navicular bone on an acquired equinovarus in non-walking children (three feet), planovalgus with major forefoot abductus in non-walking children (four feet). Among the 13 children in this series, five did not walk (seven feet) and underwent surgery because of skin wounds caused by protrusion of the head of the talus and serious mechanical problems (shoes, ortheses). Mean age at operation was 8.5 years (range 2-16 years).

The surgical procedure was part of an overall strategy combining use of ortheses, physiotherapy, and medical management. For congenital equinovarus with residual cavus, naviculectomy was performed after the usual technique for equinovarus when the navicular bone was dislocated above the medial tarsal and prevented reduction of the cavus. After extraperiosteal release, resection of the navicular bone enabled correction of the cavus. The lateral column had to be shortened in order to avoid adductus subsequent to medial-lateral length discrepancy. The same surgical technique was used for acquired equinovarus except that the navicular bone was displaced medially and above the talus. The lateral column had to be shortened. Standard procedures were applied for congenital convex feet before naviculectomy when there was major forefoot abductus after medial tarsal release and tendon lengthenings. The lateral column was not shortened since it was already too short. For planovalgus with forefoot abductus, naviculectomy was combined with release of the calcaneocuboid joint. Fibular tendons were lengthened.

Mean follow-up was two years five months (range 5 months-12 years 6 months). For the talipes equinovarus feet, the Méary Toméno angle was 24.4° on average preoperatively and 5° at last follow-up, giving a mean gain of 19.4°. For congenital convex feet, the M5-lateral calcaneal border angle was 29.7° on average preoperatively and 11.7° at last follow-up for a mean gain of 18°. For the planovalgus feet with forefoot abductus, the M5-lateral calcaneal border angle was 32.7° on average preoperatively and 12.2° at last follow-up, for a gain of 20.5° on average; the mean Méary Toméno angle was -30° preoperatively and -3° at last follow-up, for a mean gain of 27°.

For carefully selected patients, naviculectomy performed in combination with other procedures can provide appropriate correction of severe midfoot deformities in children.