Bone lengthening with external mini-fixator as treatment for brachymetatarsals.

Abstract

Introduction: Brachymetatarsia is a shortening of any metatarsal bone, mainly due to premature growth arrest of the growth plate. It is more frequent in women, the fourth and the first metatarsal being the most affected bones. The aim of this study was to evaluate the outcomes of progressive bone lengthening with external mini-fixator.
Methods: This was a retrospective, descriptive, case series study in which we analyzed the outcomes of all patients operated on with this technique in our Center. Six cases were evaluated, two of which presented bilateral brachymetatarsia. All patients were women and had brachymetatarsia of the 4th metatarsal. The average age was 14 years. The following aspects were evaluated: lengthening in millimeters and presence of complications, such as delayed consolidation, infection, metatarsophalangeal joint dislocation, metatarsophalangeal joint flexion, and patient satisfaction.
Results: On average, an increase of 15 mm was achieved. Two cases presented superficial infection at the needle insertion site. One patient progressed to metatarsophalangeal joint dislocation, and another one to metatarsophalangeal joint flexion. No neurovascular complications were observed.
Conclusions: Bone lengthening with external fixator is a safe and effective treatment. A greater length in millimeters can be achieved in comparison to one-stage lengthening, as well as an improved soft-tissue and neurovascular stretching. All complications resolved smoothly and did not affect final treatment results. Complications are similar to those described in the international literature.