Department of Orthopaedic Surgery, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, 90 Bergen Street, Suite 7300, Newark, NJ 07103, USA.
J Bone Joint Surg Am. 2013 Jun 5;95(11):995-1000. doi: 10.2106/JBJS.L.01498.
The sustentacular fragment in displaced intra-articular calcaneal fractures has historically been portrayed as a "constant fragment," bound to the talus by the interosseous and deltoid ligament complex. Operative treatment typically occurs through a lateral approach, with the remaining calcaneus being reconstructed back to the sustentaculum. We hypothesized that the sustentacular fragment in displaced intra-articular calcaneal fractures does not maintain its relationship to the talus. The purpose of this study was to characterize the frequency, magnitude, and mode of displacement of the sustentacular fragment.
Computed tomographic (CT) scans of eighty-eight patients with 100 displaced intra-articular calcaneal fractures admitted to our level-I trauma center over a five-year period were retrospectively reviewed. Basic patient demographics and mechanisms of injury were recorded. CT scans were graded according to the Sanders classification, and associated injuries were noted. Angulation and translation of the sustentacular fragment as well as gapping and intra-articular fractures of the middle facet were examined. Angulation exceeding 10° and translation of more than 3 mm were considered diagnostic of displacement.
Overall, the sustentacular fragment was displaced in forty-two of the 100 fractures. Twenty-five of one hundred calcanei had sustentacular fragment angulation of >10°, twenty-four had sustentacular translation >3 mm, twenty had fracture diastasis of the middle facet, and twenty-one had a displaced intra-articular fracture of the calcaneal middle facet. Fractures involving greater than 50% of the posterior facet (consistent with Sanders Type-B and Type-C fracture lines) demonstrated a significant increase in relative risk of angulation and translation of the sustentacular fragment as well as gapping and intra-articular fractures of the middle facet. Three-part or four-part fractures also showed a significant association with overall displacement of the sustentaculum.
This study is the first to our knowledge to quantify in a detailed manner the displacement of the sustentacular fragment as occurring with calcaneal fractures. This displacement disproves the "constant" theory of the sustentacular fragment, and it may alter the quality of the fracture reduction and affect patient outcome. An alternative surgical approach may be indicated for the treatment of certain calcaneal fracture patterns with sustentacular displacement.
Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.
在移位的关节内跟骨骨折中，支持带碎片历来被描述为“恒定碎片”，通过骨间和三角韧带复合体与距骨相连。手术治疗通常通过外侧入路进行，将剩余的跟骨重建回支持带。我们假设移位的关节内跟骨骨折中的支持带碎片不会保持与距骨的关系。本研究的目的是描述支持带碎片的移位频率、程度和方式。
回顾性分析了我院五年间收治的 88 例 100 例移位的关节内跟骨骨折患者的计算机断层扫描（CT）。记录了基本的患者人口统计学和损伤机制。根据 Sanders 分类对 CT 进行分级，并注意相关损伤。检查支持带碎片的角度和移位以及中间面的间隙和关节内骨折。角度超过 10°且移位超过 3mm 被认为是移位的诊断标准。
总体而言，在 100 例骨折中有 42 例支持带碎片发生了移位。100 个跟骨中有 25 个有大于 10°的支持带碎片角度，24 个有大于 3mm 的支持带碎片移位，20 个有中间面的骨间隙，21 个有中间面的关节内骨折。涉及后关节面大于 50%的骨折（与 Sanders 型 B 和 C 骨折线一致）显示出支持带碎片角度和移位以及中间面间隙和关节内骨折的相对风险显著增加。三部分或四部分骨折也与支持带的整体移位有显著相关性。
本研究是首次详细量化跟骨骨折中支持带碎片移位的研究。这种移位否定了支持带碎片的“恒定”理论，可能改变骨折复位的质量，并影响患者的预后。对于某些伴有支持带移位的跟骨骨折，可能需要采用替代的手术方法进行治疗。
诊断 II 级。有关证据水平的完整描述，请参阅作者说明。
