Department of Orthopaedic Surgery.
University of Pittsburgh Medical Center Children's Hospital of Pittsburgh.
J Pediatr Orthop. 2021 Jan;41(1):40-45. doi: 10.1097/BPO.0000000000001690.
Physeal instability has been shown to be associated with a higher risk of avascular necrosis (AVN) in patients with slipped capital femoral epiphysis (SCFE). The purpose of this study was to identify additional preoperative factors associated with AVN in patients with unstable SCFE.
Basic demographic information, chronicity of symptoms, and estimated duration of nonambulatory status were noted. Preoperative radiographs were used to measure the Southwick slip angle, slip severity by Wilson criteria, and epiphyseal translation. Translation was measured by 3 distinct radiographic parameters in the position demonstrating maximal displacement. Postoperative radiographs at the time of most recent follow-up were assessed for the presence of AVN. Translation measurements were tested for inter-rater reliability. Patients who developed AVN were compared with those that did not by Fisher exact test and Wilcoxon tests. Logistic regression assessed the effect of translation on the odds of developing AVN. Receiver operating characteristic curve was plotted to assess any threshold effect.
Fifty-one patients (55 hips) out of 310 patients (16%) treated for SCFE were considered unstable. Seventeen hips' unstable SCFE (31%) showed radiographic evidence of AVN. Slip severity by Wilson grade (P=0.009) and epiphyseal translation by all measurements (P< 0.05) were statistically significantly greater among patients who developed AVN. Superior translation had the best inter-rater reliability (intraclass correlation coefficient=0.84). Average superior translation in hips that developed AVN was 17.2 mm compared with 12.9 mm in those that did not (P<0.02). Although the receiver operating characteristic curve did not demonstrate a threshold effect for AVN, it did effectively rule out AVN in cases with <1 cm of superior translation. Age, sex, laterality, chronicity of prodromal symptoms or inability to bear weight, Southwick slip angle, and method of treatment did not vary with the occurrence of AVN.
Epiphyseal translation, either by Wilson Grade or measured directly, is associated with AVN in patients with an unstable SCFE.
Level II-development of diagnostic criteria.
已证实骺板不稳定性与股骨颈干骺端滑脱（SCFE）患者发生缺血性坏死（AVN）的风险增加有关。本研究的目的是确定与不稳定 SCFE 患者的 AVN 相关的其他术前因素。
记录基本人口统计学信息、症状的慢性程度和估计的非步行状态持续时间。使用术前 X 线片测量 Southwick 滑脱角、Wilson 标准的滑脱严重程度和骺板移位。在显示最大移位的位置，通过 3 种不同的放射学参数测量移位。在最近随访时的术后 X 线片评估是否存在 AVN。对测量结果进行了组内相关系数检验以评估其可靠性。通过 Fisher 确切检验和 Wilcoxon 检验比较发生 AVN 的患者与未发生 AVN 的患者。Logistic 回归评估了移位对发生 AVN 的几率的影响。绘制受试者工作特征曲线来评估任何阈值效应。
在 310 例 SCFE 患者（16%）中，51 例（55 髋）被认为不稳定。在 17 髋不稳定的 SCFE（31%）中，X 线片显示有 AVN 的证据。Wilson 分级的滑脱严重程度（P=0.009）和所有测量的骺板移位（P<0.05）在发生 AVN 的患者中均有统计学显著差异。上移位的测量结果具有最佳的组内相关系数（0.84）。发生 AVN 的髋部的平均上移位为 17.2mm，而未发生 AVN 的髋部为 12.9mm（P<0.02）。尽管受试者工作特征曲线未显示出 AVN 的阈值效应，但它确实在<1cm 的上移位时有效排除了 AVN。年龄、性别、侧别、前驱症状的慢性程度或不能负重、Southwick 滑脱角以及治疗方法与 AVN 的发生无关。
骺板移位，无论是通过 Wilson 分级还是直接测量，与不稳定的 SCFE 患者的 AVN 相关。
II 级-诊断标准的制定。
