Department of Orthopedic Surgery, Shanghai Sixth People's Hospital, Shanghai Jiao Tong University, No. 600, Yishan Road, Shanghai, 200233, People's Republic of China.
Arch Orthop Trauma Surg. 2014 Mar;134(3):389-94. doi: 10.1007/s00402-013-1844-0. Epub 2013 Dec 24.
The objective of this study was to evaluate the morphological characteristics of the posterior malleolus fragment (PMF) based on 3-D computed tomography scans, and evaluated the variability in different types of injuries (ankle fracture, spiral tibial shaft fracture and pilon fracture).
A retrospective analysis of 3-D computed tomography data of PMF from June 2011 to February 2012 was conducted in a level 1 trauma centre. The cross angle (α), fragment length ratio (FLR), fragment area ratio (FAR), sagittal angle (θ), and fragment height (FH) were measured as morphologic assessments in the Picture Archiving and Communication System (PACS).
Based on the definition of the PMF, 144 cases were brought into this study. And the PMF was described with a mean α of 25.0°, a mean FAR of 17.66 %, a mean θ of 16.1° and a mean FH of 23.06 mm. Besides, this study showed a significant difference on FAR amongst the three injuries with the FAR was 30.31 % (P < 0.05) in pilon fracture group. Respectively, although the mean θ (16.1°) indicated a vertical fracture pattern, yet no significant difference was shown amongst the three groups.
Although the PMFs appear to be highly variable, most of the PMFs were located on the posterolateral of the distal tibia, and showed features with vertical nature. The information obtained from this study will be helpful for fracture models in a future biomechanical study and for determining appropriate surgical approaches.
本研究旨在通过三维 CT 扫描评估后踝骨块（PMF）的形态特征，并评估不同类型损伤（踝关节骨折、胫骨螺旋骨折和 Pilon 骨折）中的变异性。
在一家 1 级创伤中心对 2011 年 6 月至 2012 年 2 月 PMF 的三维 CT 数据进行回顾性分析。在 PACS 中测量横角（α）、骨块长度比（FLR）、骨块面积比（FAR）、矢状角（θ）和骨块高度（FH）作为形态学评估。
根据 PMF 的定义，本研究纳入了 144 例病例。PMF 的平均α为 25.0°，平均 FAR 为 17.66%，平均θ为 16.1°，平均 FH 为 23.06mm。此外，本研究还显示，在 Pilon 骨折组中，FAR 存在显著差异（P<0.05），其 FAR 为 30.31%。分别，尽管平均θ（16.1°）表明为垂直骨折模式，但三组之间没有显示出显著差异。
尽管 PMF 似乎变化很大，但大多数 PMF 位于胫骨远端的后外侧，具有垂直性质的特征。本研究获得的信息将有助于未来生物力学研究中的骨折模型，并确定合适的手术入路。
