AO Research Institute Davos, Davos, Switzerland; University Multiprofile Hospital for Active Treatment and Emergency Medicine 'N. I. Pirogov', Sofia, Bulgaria.
AO Research Institute Davos, Davos, Switzerland; Medical University of Varna, Varna, Bulgaria.
Injury. 2022 Oct;53(10):3543-3552. doi: 10.1016/j.injury.2022.06.036. Epub 2022 Jun 25.
Treatment of comminuted intraarticular calcaneal fractures remains controversial and challenging. The aim of this study was to investigate the biomechanical performance of three different methods for fixation of such fractures. Comminuted calcaneal fractures, including Sanders III AB fracture of the posterior facet and Kinner II B fracture of the calcaneocuboid joint (CCJ) articular calcaneal surface, were created in 18 human cadaveric lower legs by osteotomizing. The ankle joint, medial soft tissues and midtarsal bones along with their ligaments were preserved. The specimens were randomized to three groups for fixation with either (1) 2.7 mm variable-angle locking lateral calcaneal plate (Group 1), (2) 2.7 mm variable-angle locking anterolateral calcaneal plate in combination with one 4.5 mm and one 6.5 mm cannulated screws (Group 2), or (3) interlocking calcaneal nail with 3.5 mm screws in combination with three separate 4.0 mm cannulated screws (Group 3). All specimens were biomechanically tested to failure under axial loading in midstance foot position. Each test commenced with a quasi-static compression ramp from 50 to 200 N, followed by progressively increasing cyclic loading at 2 Hz. Starting from 200 N, the peak load of each cycle increased at a rate of 0.2 N/cycle. Interfragmentary movements were captured by motion tracking. In addition, mediolateral X-rays were taken every 250 cycles with a triggered C-arm. Böhler angle after 5000 cycles (1200 N peak load) increased significantly more in Group 1 compared to both other groups (P ≤ 0.020). Varus deformation of 10° between the calcaneal tuberosity and the lateral calcaneal fragments was reached at significantly lower number of cycles in Group 1 compared the other groups (P ≤ 0.017). Both cycles to 10° plantar gapping between the anterior process and the calcaneal tuberosity fragments, and 2 mm displacement at the CCJ articular calcaneal surface revealed no significant differences among the groups (P ≥ 0.773). From a biomechanical perspective, treatment of comminuted intraarticular calcaneal fractures using anterolateral variable-angle locking plate with additional longitudinal screws or interlocked nail in combination with separate transversal screws provides superior stability as opposed to lateral variable-angle locked plating only.
治疗粉碎性关节内跟骨骨折仍然存在争议和挑战。本研究旨在探讨三种不同方法固定此类骨折的生物力学性能。通过截骨术在 18 具人体下肢尸体标本中造成粉碎性跟骨骨折，包括后关节面 Sanders III AB 型骨折和跟距关节（CCJ）关节面的 Kinner II B 型骨折。保留踝关节、内侧软组织和中跗骨及其韧带。标本随机分为三组，分别采用（1）2.7mm 可角度锁定外侧跟骨板（组 1）、（2）2.7mm 可角度锁定前外侧跟骨板联合 1 枚 4.5mm 和 1 枚 6.5mm 空心螺钉（组 2）或（3）带 3.5mm 螺钉的交锁跟骨钉联合 3 枚单独的 4.0mm 空心螺钉（组 3）固定。所有标本均在中足位轴向加载下进行生物力学失效测试。每次测试均从 50 至 200N 的准静态压缩斜坡开始，然后以 2Hz 的频率进行逐渐增加的循环加载。从 200N 开始，每个循环的峰值负载以 0.2N/循环的速率增加。通过运动跟踪捕获骨折间的运动。此外，每隔 250 个循环用触发式 C 臂拍摄外侧 X 线片。在 5000 个循环（1200N 峰值负载）后，Böhler 角在组 1 中显著高于其他两组（P≤0.020）。在组 1 中，距骨结节和外侧跟骨碎片之间的内翻变形达到 10°所需的循环数明显低于其他两组（P≤0.017）。在前突和距骨结节碎片之间达到 10°的跖侧间隙和 CCJ 关节面的 2mm 位移的循环数在各组之间无显著差异（P≥0.773）。从生物力学角度来看，与仅外侧可角度锁定钢板相比，前外侧可角度锁定钢板联合附加纵向螺钉或交锁钉与单独的横向螺钉治疗粉碎性关节内跟骨骨折提供了更好的稳定性。
