Rare condition of congenital intermetatarsal coalition with deformity of the fifth metatarsal and symptomatic lesion on the plantar aspect of the foot.
Case Report
Congenital coalitions are defined as abnormal osseous or fibrocartilaginous bridges between two bones due to failure of embryonic segmentation. In the foot, tarsal bone coalitions are commonly seen, but intermetatarsal coalition is extremely rare and very few cases have been reported in literature to date. We report a case of a unilateral, congenital metatarsal coalition between the fourth and fifth metatarsal bones in a kid in his middle childhood, who presented with unilateral chronic forefoot pain on activity with keratosis under the fifth metatarsal head.A thorough history with clinical examination revealed a deformed, plantar flexed fifth toe with callosity formation under the head of the fifth metatarsal head. Further radiographs revealed a bony coalition between the fourth and fifth metatarsal base with a subtle cavus foot and markedly increased fifth ray declination angle. A corrective proximal oblique osteotomy was done at the fifth metatarsal base and held with Kirschner wires (K-wires) and the limb was immobilised for a period of 6 weeks. The patient followed up with serial radiograph examinations and at the end of 6 weeks, K-wires were removed and repeat weight-bearing views were taken and evaluated.After the surgical intervention, there is symptomatic relief in pain as well as a reduction in the callosity and deformity.Intermetatarsal coalition is a very rare condition. The definitive management for symptomatic cases is corrective surgery to achieve normal biomechanics in the foot as well as pain-free weight bearing. Proximal osteotomy at the fifth metatarsal base gave excellent results in our patient.
