Callahan Ryan, Juliano Paul, Aydogan Umur, Clayton Justin
Penn State Milton S. Hershey Medical Center, Hershey, Pennsylvania.
Foot Ankle Spec. 2018 Dec;11(6):543-547. doi: 10.1177/1938640018770255. Epub 2018 Apr 16.
. Tibiotalocalcaneal (TTC) nails are often used for complex hind foot arthrodesis and deformity correction. The natural valgus alignment of the hindfoot creates a challenge to optimum placement of the guidewire and eventual nail with a straight or valgus-curved nail. . Five fresh frozen cadavers were used for placement of a TTC guidewire with standard anterior-posterior (AP), lateral, and Harris axial heel views as a reference for proper placement. The limb was then rotated 15°, 30°, and 45° both internally and externally to evaluate the perceived amount of osseous purchase within the calcaneus. The TTC nail was then inserted and dissection was performed to demonstrate proximity of the nail to the sustentaculum tali and neurovascular structures. . A 30° internal rotation Harris axial heel view demonstrated the most accurate representation of osseous purchase within the calcaneus with the guidewire and nail placement. When the guidewire was placed with standard imaging the nail was often ultimately placed in close proximity to the sustentaculum tali and neurovascular structures. . Careful placement of the guidewire prior to reaming and nail placement should be undertaken to avoid neurovascular injury and to increase osseous purchase. For optimal guidewire placement, the authors suggest using appropriate anatomic landmarks and using a 30° internally rotated Harris axial heel view to verify correct placement. Level V: Expert opinion.
胫距跟(TTC)钉常用于复杂的后足关节融合术和畸形矫正。后足的自然外翻对线给导丝和最终使用直钉或外翻弯曲钉的最佳放置带来了挑战。使用五具新鲜冷冻尸体,在标准的前后位(AP)、侧位和哈里斯跟骨轴位视图下放置TTC导丝,作为正确放置的参考。然后将肢体分别向内和向外旋转15°、30°和45°,以评估在跟骨内的骨抓持量。接着插入TTC钉并进行解剖,以显示钉子与载距突和神经血管结构的接近程度。30°内旋哈里斯跟骨轴位视图显示了导丝和钉子放置时跟骨内骨抓持的最准确表现。当使用标准成像放置导丝时,钉子最终往往放置在靠近载距突和神经血管结构的位置。在扩孔和放置钉子之前,应仔细放置导丝,以避免神经血管损伤并增加骨抓持。为了实现最佳的导丝放置,作者建议使用适当的解剖标志,并使用30°内旋哈里斯跟骨轴位视图来验证正确放置。V级:专家意见。