Treatment of displaced proximal fifth metatarsal fractures using a new one-step fixation technique.

Background: Fractures of the tuberosity of the fifth metatarsal are common after foot twisting injuries, and operative treatment is recommended in cases of displacement. The purpose of this study was to report the radiologic outcome and clinical results of displaced fractures of the tuberosity of the fifth metatarsal treated using fine-threaded K-wires (FFS).

Methods: In 3 years' time, in a total of 35 cases, patients had an initial fracture displacement of more than 2 mm for isolated extraarticular fractures and an involvement of the cuboidal joint surface of more than 30%. After 15 months to 60 months (mean, 30.6), 32 of these patients participated in a clinical follow-up examination and questionnaire according to a clinical rating system for midfoot fractures. Radiologic outcome measurements were the remaining postoperative intraarticular step off and the healing time.

Results: The mean midfoot scale score was 96.5 points. All the patients returned to prior activities after operative treatment. Seven patients reported minor pain during longer periods of walking. One patient with secondary wound healing experienced frequent pain. Radiologically, in 32 of 35 patients, there was a remaining step off of less than 1 mm and in three patients less than 3 mm. All fractures except one healed within the first 3 months to 6 months.

Conclusion: Operative treatment of displaced proximal fifth metatarsal fractures using the FFS system leads to a good clinical and radiologic outcome. The FFS system provides a new treatment option for this fracture type.