Treatment of serious brachymetatarsia by gradual metatarsal elongation combined with bone graft

CHEN Hui-hao; ZHAO Liang-yu; GUO Xing-feng; YIN Gang; LEI De-qiao; HOU Chun-lin

doi:10.3969/j.issn.2095-252X.2014.07.012

Abstract：Objective To investigate the outcomes of gradual metatarsal elongation combined with bone graft in the treatment of serious brachymetatarsia, and to introduce the advantages of this operative method.Methods From 2006 to 2012, 10 patients with brachymetatarsia ( 14 metatarsals ) were treated, including 4 patients with bilateral brachymetatarsia of the 4th ray, 5 patients with unilateral brachymetatarsia of the 4th ray and 1 patient with brachymetatarsia of the 1st ray. There were 9 females and 1 male, whose age ranged from 13 to 30 years old. The inclusion criteria was that the metatarsal bone was shortened for over 20 mm. Based on the preoperative radiographs, the mean shortened length was 2.3 cm ( range: 2.0-2.7 cm ). In the ifrst stage, metatarsal osteotomy was performed with the oscillating micro-saw in the middle part with the dorsal approach, and then the Orthoifx unilateral external fixator was installed. The traction of 5 mm was achieved during the operation. The extension was done from the 2nd day after the surgery at the rate of 0.5 mm twice a day, each morning and evening. The extended length was 0.4 mm in the morning and 0.35 mm in the evening 2 weeks later. In the second stage, the iliac bone graft was taken out and the external ifxator was removed when the metatarsal bone was extended to the expected length. The mini-plate was used in the internal ifxation. The mean follow-up period was 14 months ( range: 12-18 months ).Results The postoperative radiographs showed bony union was achieved in 13 of 14 metatarsals at 12 weeks, and in all 14 metatarsals at 18 weeks after the operation. The mean extended length was 22.5 mm and the mean percentage of extension was 39.5%. Parabolic recovery was realized in the metatarsals. The function was evaluated according to the standard of the American Orthopedic Foot and Ankle Society ( AOFAS ). The paired t-test was used to analyze the scores preoperatively and at 12 weeks after the operation. The sample mean of the difference values was -50.29, and the differences were statistically signiifcant (P<0.01 ). The average postoperative score was 84.71 points, and there were 8 excellent cases and 6 good cases. No obvious complications were found, and all the patients felt basically or completely satisfied with the extension and the appearance and function of the forefoot.Conclusions Gradual metatarsal elongation combined with bone graft is recommended in the treatment of serious brachymetatarsia, and the satisfactory extension could be achieved with the advantages of quick recovery and less complications.