[Immediate metatarsal lengthening for congenital brachymetatarsia]

Objective: To explore clinical efficacy of congenital brachymetatarsia with immediate metatarsal lengthening.

Methods: From March 2015 to December 2020, 7 patients with brachymetatarsia were treated, including 6 females and 1 male;aged range from 18 to 30 years old;there were 5 patients with metatarsal microsomia on one foot, 2 patients with metatarsal microsomia on the first and fourth right foot, and immediate extension of metatarsal microsomia on the first and fourth right foot;two patients were short metatarsal bones of both feet. The length of short metatarsal bone, length of normal metatarsal bone, distance of short metatarsal bone and healing of bone graft were observed before and 12 months after operation. American Orthopaedic Foot and Ankle Society (AOFAS) scores were used to evaluate clinical efficacy and observe complications.

Results: Seven patients were followed up for 12 to 24 months. All metatarsal bones were extended to satisfactory length and bone graft were healed completely. Metatarsal length and shortening distance were improved from 3.55 to 5.90 cm and 0.77 to 1.46 cm before operation to 4.31 to 6.87 cm and 0.04 to 0.57 cm at 12 months after operation. Postoperative X-ray of the affected foot at 12 months showed bone healing was achieved between metatarsal bone and bone graft in 7 patients, and the parabolic shape of the distal metatarsal bone recovered after operation. AOFAS scores improved from 40 to 70 before operation to 88 to 95 points at 12 months after operation, and 6 patients were excellent and 1 good.

Conclusion: Immediate extension of metatarsal bone for congenital brachymetatarsia, the transplanted bone grew well during the process of bone grafting healing, the occurrence of bone nonunion was reduced, the short metatarsal bone was restored to a satisfactory length, and the toe function restored well.