[Metatarsal and toe fractures]

Treatment of two or more metatarsal fractures

INTRODUCTION

Metatarsal fractures are the most common type of foot fracture. When surgical treatment is needed, pinning is typically used, either percutaneous or open. However, this fixation method has been criticized by some authors who lament residual malunion and prefer to use plate and/or screws. The primary objective of our study was to compare the outcomes of K-wire versus plate and/or screw fixation for the surgical treatment of two or more metatarsal fractures. The secondary objective was to evaluate the factors that contribute to poor outcomes and complications. We hypothesized that plate and/or screw fixation will produce better functional outcomes than K-wire fixation.

MATERIALS AND METHODS

This was a prospective and retrospective multicenter study carried out between 1 January 2010 and 1 June 2018 with a minimum follow-up of 12 months. Three functional scores were determined (AOFAS, FAAM and SF12 physical and mental) preoperatively, postoperatively and at the final assessment. We evaluated the outcomes in the entire study population and in four injury type subgroups, including one with isolated metatarsal fractures to control analysis bias.

RESULTS

Our analysis compiled data from 165 patients (123 men, 42 women) who had a mean age of 38 years (16-82). The mean follow-up time was 27.9months (10-120). There were no complications in 130 patients (79%). Skin necrosis occurred in 25 patients (15%). The FAAM score was significantly higher in the plate and/or screw group 70.2 (17-84) versus 60.3 (31-84) in the K-wire group (P=0.033). The 78 (19-100) AOFAS was higher, but not significantly, in the plate and/or screw group versus 70 (12-100) in the K-wire group (P=0.144).

CONCLUSION

Trauma to the foot that causes a fracture in two or more metatarsals often occurs due to a crush injury (39%). The frequency of associated bone lesions means that a preoperative CT scan should be done routinely to analyze the injury pattern and determine the best treatment. The fixation method should be adapted to the local conditions; when possible, it is preferable to use rigid fixation with plates and/or screws as it yields better functional outcomes.

LEVEL OF EVIDENCE

IV; study with retrospective component.

[Fixation of displaced fifth metatarsal shaft and neck fractures]

OBJECTIVE

Open reduction and internal fixation of grossly dislocated fifth metatarsal shaft and neck fractures aims at restoration of the anatomical structure of the forefoot. The goal is to restore length, axis, rotation and joint position, while observing the metatarsal index (Maestro curve).

INDICATIONS

Grossly dislocated and/or open shaft/neck fractures of the fifth metatarsal; combined fractures of the forefoot involving the fifth metatarsal.

CONTRAINDICATIONS

Lack of consent to surgery. Overall critical (life-threatening) general condition preventing surgery to the extremities. Contaminated or infected soft tissues.

SURGICAL TECHNIQUE

Depending on the planned method of fixation, open reduction is usually conducted via a lateral approach centrally above the easily palpable metatarsal V shaft. The incision lies above the glabrous skin of the sole. For markedly shortened and multifragment subcapital and shaft fractures of the fifth metatarsal, open reduction and plate fixation is the method of choice. Interlocking plates with a screw diameter of 2.0-2.4 mm are preferred to avoid later soft tissue irritation. Anatomic reconstruction is carried out under longitudinal traction at the fifth toe using small reduction clamps and, if necessary, temporary K‑wire fixation. If the fragments are large enough, one or more interfragmentary lag screws can be used for fracture compression. A straight or condylar plate is used for internal fixation. Long spiral fifth metatarsal shaft fractures may alternatively be fixed with screws. In the case of transverse or subcapital fractures, percutaneous antegrade or retrograde medullary wiring with two Kirschner wires should be considered.

POSTOPERATIVE MANAGEMENT

Following surgical treatment, rest and elevation of the injured leg, and local cooling are indicated. Subsequently, mobilization with partial weight bearing (20 kg) in foot orthosis or cast shoe for 6 weeks.

RESULTS

Even grossly displaced fractures of the fifth metatarsal shaft have a good to excellent prognosis following surgical treatment with high union rates and rare complications. Undisplaced and mildly displaced fractures can be successfully managed nonoperatively with 6 weeks of weight bearing as tolerated in a stable orthosis or cast shoes.