Departments of Diagnostic, Interventional and Pediatric Radiology.
Department of Orthopedic surgery, Child and Young Adult Hip Preservation Program at Boston Children's Hospital, Boston, MA.
J Pediatr Orthop. 2022;42(10):e963-e970. doi: 10.1097/BPO.0000000000002249. Epub 2022 Sep 13.
Slipped capital femoral epiphysis (SCFE) is the most common hip disorder in adolescent patients that can result in complex 3 dimensional (3D)-deformity and hip preservation surgery (eg, in situ pinning or proximal femoral osteotomy) is often performed. But there is little information about location of impingement.Purpose/Questions: The purpose of this study was to evaluate (1) impingement-free hip flexion and internal rotation (IR), (2) frequency of impingement in early flexion (30 to 60 degrees), and (3) location of acetabular and femoral impingement in IR in 90 degrees of flexion (IRF-90 degrees) and in maximal flexion for patients with untreated severe SCFE using preoperative 3D-computed tomography (CT) for impingement simulation.
A retrospective study involving 3D-CT scans of 18 patients (21 hips) with untreated severe SCFE (slip angle>60 degrees) was performed. Preoperative CT scans were used for bone segmentation of preoperative patient-specific 3D models. Three patients (15%) had bilateral SCFE. Mean age was 13±2 (10 to 16) years and 67% were male patients (86% unstable slip, 81% chronic slip). The contralateral hips of 15 patients with unilateral SCFE were evaluated (control group). Validated software was used for 3D impingement simulation (equidistant method).
(1) Impingement-free flexion (46±32 degrees) and IRF-90 degrees (-17±18 degrees) were significantly ( P <0.001) decreased in untreated severe SCFE patients compared with contralateral side (122±9 and 36±11 degrees).(2) Frequency of impingement was significantly ( P <0.001) higher in 30 and 60 degrees flexion (48% and 71%) of patients with severe SCFE compared with control group (0%).(3) Acetabular impingement conflict was located anterior-superior (SCFE patients), mostly 12 o'clock (50%) in IRF-90 degrees (70% on 2 o'clock for maximal flexion). Femoral impingement was located on anterior-superior to anterior-inferior femoral metaphysis (between 2 and 6 o'clock, 40% on 3 o'clock and 40% on 5 o'clock) in IRF-90 degrees and on anterior metaphysis (40% on 3 o'clock) in maximal flexion and frequency was significantly ( P <0.001) different compared with control group.
Severe SCFE patients have limited hip flexion and IR due to early hip impingement using patient-specific preoperative 3D models. Because of the large variety of hip motion, individual evaluation is recommended to plan the osseous correction for severe SCFE patients.
Level III.
slipped capital femoral epiphysis (SCFE) 是青少年患者中最常见的髋关节疾病，可导致复杂的三维 (3D) 畸形和髋关节保存手术（例如原位钉固定或股骨近端截骨术）。但关于撞击的位置知之甚少。目的/问题：本研究的目的是评估 (1) 无撞击的髋关节屈曲和内旋 (IR)，(2) 在早期屈曲（30 至 60 度）时的撞击频率，以及 (3) 在未治疗的严重 SCFE 患者中，使用术前 3D 计算机断层扫描 (CT) 进行撞击模拟的 90 度屈曲时的髋臼和股骨撞击的位置IRF-90 度（IRF-90 度）和最大屈曲时的髋臼和股骨撞击的位置。
对 18 例（21 髋）未经治疗的严重 SCFE（滑动角>60 度）患者的 3D-CT 扫描进行回顾性研究。使用术前 CT 扫描对术前患者特定的 3D 模型进行骨骼分割。三名患者（15%）患有双侧 SCFE。平均年龄为 13±2（10 至 16）岁，67%为男性患者（86%不稳定滑脱，81%慢性滑脱）。对 15 例单侧 SCFE 患者的对侧髋关节进行评估（对照组）。使用经过验证的软件进行 3D 撞击模拟（等距法）。
（1）与对侧相比，未经治疗的严重 SCFE 患者的无撞击屈曲（46±32 度）和 IRF-90 度（-17±18 度）（ P <0.001）明显降低。（2）严重 SCFE 患者在 30 和 60 度屈曲时（48%和 71%）撞击的发生率明显（ P <0.001）高于对照组（0%）。（3）髋臼撞击冲突位于前上（SCFE 患者），在 IRF-90 度时大部分位于 12 点钟（70%在 2 点钟时最大屈曲）。股骨撞击位于前上至前下股骨干骺端（2 至 6 点钟之间），在 IRF-90 度时 40%在 3 点钟，40%在 5 点钟，在最大屈曲时位于前干骺端（40%在 3 点钟），与对照组相比，撞击的频率明显（ P <0.001）不同。
使用术前特定患者的 3D 模型，严重 SCFE 患者的髋关节屈曲和内旋受限，原因是髋关节早期撞击。由于髋关节运动的种类繁多，建议对严重 SCFE 患者进行个体化评估，以计划进行骨骼矫正。
III 级。
