To evaluate the clinical results of lengthening in first brachymetatarsia using a distraction osteogensis with an external fixator.

Fifteen cases in nine patients, who had received firstmetatarsal distraction osteogenesis from January 1996 to December 2002, were enrolled in this study. At the final follow-up, the application time of the external fixator was measured and the percentage of lengthening, healing index, complication rate, and the patients satisfaction was analyzed. The patients satisfaction was evaluated using the American Orthopedic Foot and Ankle Society (AOFAS) scores, which were scored according to the level of stiffness, pain, function, and alignment.

The score according to the AOFAS-Hallux Metatarsophalangeal joint and Inter-Phalangeal joint scale was excellent in 13 patients and good in 2. All patients were satisfied with the procedure. The average percentage of lengthening was 48.7%. The average healing index was 72.8 days/cm. The major complication was a cavus foot, which was noticed in four feet. All the first toes showed some decrease in motion at the metatarsophalangeal joint. The other complications were hallux valgus, angulation of the metatarsals, and a pin tract infection each in two feet.

Distraction osteogenesis is an effective method for first brachymetatarsia. However, excessive lengthening can cause potential complications.