Immediate Weight-Bearing Protocol for the Determination of Ankle Stability in Patients With Isolated Distal Fibular Fractures.

Abstract

To evaluate an alternative protocol for allowing immediate weight-bearing (WB) as tolerated in a functional walking boot in patients with a medial clear space (MCS) of less than 4 mm on nonstressed initial radiographs with subsequent WB radiographs at 1-week follow-up to determine if this can differentiate stable from unstable distal fibular fractures. Retrospective case series. Level 1 trauma center. Seventy-nine patients who sustained an isolated distal fibular fracture with an MCS less than 4 mm on initial non-weight-bearing radiographs during a 6-year period. Patients with MCS less than 4 mm on 1-week radiographs were treated nonoperatively. Patients with MCS greater than or equal to 4 mm were treated operatively. Medial clear space measurements on WB ankle radiographs at the time of radiographic bony union. Two of the 79 (2.5%) patients had an MCS greater than 4 mm at 1-week follow-up with WB radiographs and underwent operative fixation. The remaining 77 patients were treated nonoperatively. All 77 patients had an MCS less than 4 mm on WB radiographs at the time of radiographic healing. These results suggest that our immediate weight-bearing protocol may be an effective method for determination of functional ankle stability only in the setting of an isolated distal fibula fracture with MCS less than 4 mm. However, it should be cautioned that careful evaluation of WB radiographs for joint asymmetry and/or MCS widening is mandatory to avoid poor outcomes. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.