Management and classification of the fracture of lateral process of talus: An overview and literature update

Figure 4 Boack's classification of the fracture of talar process. A: Boack's type 1a, extra-articular fracture of lateral process; B: Boack's type 1b, isolated fracture of the medial tubercle of the posterior talar process; C: Boack's type 1c, intra-articular fracture of the lateral process; D: Boack's type 2a, fracture of the lateral process of talus involving only the subtalar joint but not the talofibular joint; E: Boack's type 2b, fracture of the lateral tuberosity of the posterior talar process; F: Boack's type 3a, a simple fracture of the lateral talar process with involvement of both the talofibular and posterior subtalar articular surfaces; G: Boack's type 3b, comminuted fracture of the lateral talar process; H: Boack's type 3c, comminuted fracture of the posterior talar process with involvement of both lateral and medial tuberosity; I: Boack's type 4, comminuted fracture of the lateral talar process combined with luxation of the subtalar joint; J: Boack's type 4, comminuted fracture of the posterior talar process with luxation of the subtalar joint.