Use of an Acrylic Mold for Mortise View Improvement in Ankle Fractures: A Feasibility Study

We investigated an acrylic mold for use in obtaining ankle radiographs in 31 consecutive patients with ankle fracture. The radiologic examination consisted of routine lateral and mortise views, with the same views procured with the use of the acrylic mold to position the ankle. Radiographic evidence of ankle displacement was ascertained using both sets of radiographs, and 3 radiographic spaces (lateral talofibular, central talotibial, and medial talotibial) were considered identifiable on the mortise view. The routine radiographs identified 58 joint spaces (62.37%) and the use of the acrylic mold showed 74 (79.57%; p < .0001). On the basis of the medial clear space, surgical repair was indicated in 6 patients (19.36%) using the routine radiographs and in 8 (25.81%) using the radiographs procured with the acrylic mold (p = .317). On the basis of fibular dislocation alone, surgical repair was indicated in 12 patients (38.71%) using the routine radiographs and in 15 (48.39%) using the radiographs procured with the acrylic mold (p = .083). On the basis of medial clear space and fibular dislocation, surgery was indicated in 12 patients (38.71%) using the routine radiographs and in 16 (51.61%) using the radiographs procured with the acrylic mold (p = .046). The sensitivity and specificity of the radiographs obtained with the acrylic mold was 75% and 100%, respectively. We concluded that the use of the acrylic mold improved the radiographic diagnostic accuracy compared with routine radiographs for the treatment of ankle fractures.