Coral A
Skeletal Radiol. 1987;16(4):298-303. doi: 10.1007/BF00361472.
The os subtibiale is a rare, genuine accessory bone and normal variant related to the posterior colliculus of the medial malleolus. Only one example was found in the radiographs of the ankles of 700 patients examined. It can be differentiated from other ossicles in this region by its relatively large size, its rounded and well-defined shape, and its posterior position. Ossicles related to the anterior colliculus, which forms the tip of the malleolus, are smaller and were present in 15 ankles (2.1%). These may represent unfused secondary ossification centres. Post-traumatic ossification is the probable explanation for the small, angular and less well-defined ossified elements encountered. The overall incidence of ossification in the subtibial region in the 700 ankles studied was 4.6%.
胫下骨是一种罕见的真性副骨，是与内踝后丘相关的正常变异。在700例接受检查的踝关节X线片中仅发现1例。它可通过相对较大的尺寸、圆形且边界清晰的形状以及后方位置与该区域的其他小骨相鉴别。与构成踝尖的前丘相关的小骨较小，在15个踝关节中出现（2.1%）。这些可能代表未融合的次级骨化中心。创伤后骨化可能是所遇到的小的、有角且边界欠清晰的骨化成分的原因。在研究的700个踝关节中，胫下区域骨化的总体发生率为4.6%。
