Lateral Talar Dome Access Utilizing Temporary Invasive Distraction

Background: Autogenous osteochondral grafting is an operative option for the treatment of osteochondral lesions of the talus (OLT). Graft implantation often requires an osteotomy to gain perpendicular access to the recipient site. The purpose of this study was to determine the relative contributions of soft tissue releases, osteotomies, and invasive distraction on perpendicular access to the lateral talar dome. We hypothesized that temporary invasive distraction (TID) would provide greater perpendicular access than anterolateral arthrotomy alone and similar access compared to an anterolateral tibial osteotomy. Materials and Methods: Eight fresh frozen cadaveric limb specimens were utilized. An anterolateral arthrotomy was performed and an osteochondral plug was harvested as far posterior as allowed. An additional two Kirschner wires were placed to mark the borders of the area of access. This process was then repeated utilizing: 1) an external fixator for distraction alone, 2) an anterolateral tibial osteotomy alone (with distraction released), and 3) an anterolateral tibial osteotomy (with distraction reapplied). The area accessible as well as the anterior to posterior (AP) access was measured and recorded for each approach. Results: The approach utilizing TID provided greater access than arthrotomy with regard to AP access ( p = 0.0007) as well as area ( p = 0.003). The approach utilizing TID alone was equivalent to the anterolateral tibial osteotomy with regard to AP access as well as area. TID combined with osteotomy provided greater access than the TID or osteotomy approaches alone with regard to AP access ( p = 0.01 and p = 0.02, respectively) and greater access than the external fixator alone with regard to area ( p = 0.02). Conclusion: Temporary distraction utilizing external fixation provides greater perpendicular access than anterolateral arthrotomy and access equivalent to anterolateral osteotomy alone. Clinical Relevance: Utilizing TID may obviate the morbidity and possible complications associated with osteotomy and may prove to be a valuable tool in the treatment of osteochondral lesions of the talus.