Surgical Results of Zones I and II Fifth Metatarsal Base Fractures Using Hook Plates

SLR- January 2014- Marc Jones

Reference: Choi JH, Lee KT, Lee YK, Lee JY, Kim HR, Orthopedics 2013. Jan; 36(1):e71-4.

Reviewed By: Marc Jones, DPM
Residency Program: Madigan Army Medical Center

Podiatric Relevance: Fifth metatarsal base fractures are one of the most common forefoot fractures and guidelines for treatment of these fractures are controversial. Zone I and II fractures are generally treated conservatively but with significant displacement or comminution may require open reduction internal fixation. Many techniques have been described for fixation of Zone I and II fifth metatarsal base fractures with varying success.

Methods: Seventeen patients with Zone I and II fifth metatarsal fractures with comminution or displacement of less than 2 mm were fixated with a hook plate, one compression screw and three cortical screws. Non-displaced fractures, Zone III fractures and any fracture with other combined foot and ankle fractures were excluded. AOFAS midfoot scores were reported preoperatively and one-year postoperatively. All fractures had CT scans performed postoperatively for monitoring of healing progress. 

Results: Eleven Zone II fractures and six Zone I fractures were treated. Mean patient agewas 46 years (19-77), mean time to fixation from injury was five days (1-9). Mean follow up was 17 months (12-28). Mean preoperative AOFAS scores were 48 points (35-60) and one year post-operative AOFAS scores were 91 points (85-100). Mean time to boney union was 54 days (38-74) and a return to all prior activities of 74 days (63-98). One complication consisting of symptomatic hardware occurred, which was treated with hardware removal. All fractures achieved full union. Patients were non-weight bearing for three weeks after surgery and then transitioned to weight bearing as tolerated in a cast boot for another three weeks.

Conclusions: The authors concluded that surgical treatment of displaced and comminuted fifth metatarsal fractures allows an early return to weight bearing and a predictable union rate when compared to conservative treatment. Although this is a small sample size this study gives an effective alternative fixation method for displaced and comminuted Zone I and II fifth metatarsal fractures. This fixation method could be used when intramedullary screw fixation may be challenging due to the fracture pattern or degree of comminution present.