![]() ![]() The value of any classification system is based on its ability to guide treatment or provide prognostic information. Medial malleolar fractures can also occur in up to 28% of patients. This results dorsomedial talar neck comminution and a predilection of the talar neck to fall into varus and extension malalignment. However, most injuries also involve a rotational component (hindfoot supination) causing the talar neck to impact against the medial malleolus. The classically described mechanism of talar neck fracture is forced ankle dorsiflexion combined with axial loading, resulting in the talar neck impacting the anterior plafond edge. Although the trabecular bone in the talar body is in the same direction as body weight transmission, transferring body weight from the plafond to the foot, there is an abrupt change in direction of the trabeculae at junction of the talar body and neck, making the talar neck susceptible to fracture. The osteology of the talar neck is also unique, as it has less trabecular bone than the head or body, and the trabeculae are in a different orientation than the body. However, more recent gadolinium-enhanced MRI cadaveric studies have demonstrated a more robust antegrade blood supply, which may account for the fact that not every talar neck fracture progresses to osteonecrosis (ON). Classically, the importance of the neck not only lies in that it is the structural connection between the head and body, but that it is also the conduit for the talar body’s retrograde blood supply. The neck is relatively devoid of articular cartilage. The talar neck is angled medially (10–44°) and plantarly (5–50°) with respect to the body. The superior portion of lateral malleolus also articulates with the lateral process of the talus. The medial and lateral extensions of the superior talar articular surface also articulate with their respective ankle malleoli. As a result, the talus serves as the key stone to multiple complex articulations with the tibia superiorly (tibiotalar joint), calcaneus inferiorly (subtalar joint), and the navicular anteriorly (talonavicular joint). The talus has no muscular attachments and more than half of the talus is covered by articular cartilage. The talus is broken up into three regions: head, neck, and body. ![]()
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