Objectives: To quantify the radiographic tibia and fibula shaft fracture characteristics that are associated with a concomitant ipsilateral ankle injury. Design: Retrospective case-control study. Setting: Academic level I trauma center. Patients: Seventy-one adult patients with an operatively treated tibial shaft fracture met the inclusion/exclusion criteria. Intervention: Preoperative radiographs were categorized according to tibia and fibula fracture pattern, location and spatial relationship to each other. Preoperative computed tomographic scans were then evaluated to assess for the presence of an articular ankle injury. Main Outcome Measurements: (1) incidence of concomitant tibial shaft fracture and ipsilateral ankle injury; and (2) statistical association between tibia and fibula fracture characteristics in patients with and without an ipsilateral ankle fracture. Results: Thirty-five of 71 (49.3%) tibial shaft fracture patients had a concomitant ipsilateral ankle injury. Of these, 31 (88.6%) ankle injuries occurred in patients with a spiral pattern tibia fracture of the distal third diaphysis (P < 0.001). A spiral pattern tibia fracture, a distal one-third tibial shaft fracture location, or a spiral pattern fibula fracture all were significantly associated with the presence of an ipsilateral ankle injury (P ≤ 0.001; P = 0.001; and P = 0.002, respectively). Patients with either a transverse pattern or absent fibula fracture, a nonspiral pattern tibia fracture, or a midshaft diaphyseal tibia fracture location were significantly less likely to have an associated ankle injury (P ≤ 0.001; P ≤ 0.001; and P = 0.012, respectively). Conclusions: Ipsilateral ankle fractures are commonly associated with tibial shaft fractures, specifically distal one-third spiral type injuries. Recognition of an associated ankle injury is important as it can alter operative and postoperative management. Clinical studies are needed to examine patient outcomes with or without ipsilateral ankle injury to determine the clinical significance of this entity.
- concomitant ankle injury
- predictive radiographic patterns
- tibial shaft fracture