Kim Jung-Min, Yoon Hyung-Ku, Moon Gi-Ho, Ahn Joo-Suk, Yang Kyu-Hyun
Department of Orthopedic Surgery, Armed Forces Capital Hospital, Seongnam, Korea.
Department of Orthopedic Surgery, St. Peter's General Hospital, Seoul, Korea.
Clin Orthop Surg. 2025 Feb;17(1):71-79. doi: 10.4055/cios24061. Epub 2024 Dec 9.
Decreased acetabular version and posterior acetabular coverage of the femoral head have been regarded as the leading causes of sport-related posterior hip dislocation or subluxation. This study aimed to examine the posterior acetabular coverage of the femoral head in 21 patients who sustained posterior hip dislocation or subluxation during sport activities.
The anterior and posterior acetabular rims on 3-dimensional computed tomography (3D-CT) images were delineated on the normal side in these patients. Radiologic signs, including crossover and posterior wall signs, were examined. The fracture center level (FCL) of the posterior acetabular wall was identified on axial CT images of the injured hip and the level was marked on the normal side. The difference in the femoral head coverage by posterior and anterior acetabular rims was measured by measuring the horizontal distance between anterior and posterior acetabular rims at the FCL (posterior-anterior [P-A] index). The acetabular version was measured at the femoral head and FCL using axial CT images of the normal side. Femoral head coverage by the posterior acetabular wall on the normal side was measured using 3D-CT (areal coverage).
The crossover and posterior wall signs were positive in 14 and 10 patients, respectively, in 3D-CT images. The FCL was evenly distributed in the proximal half of the posterior acetabular wall. Seven patients had a P-A index of ≤ 0, and all were positive for the crossover sign. The anterior acetabular rim was relatively prominent in these patients. The acetabular version was lower at the FCL than at the femoral head center ( < 0.001). The proximal half areal coverage of the posterior acetabular wall was significantly smaller than the whole areal coverage ( = 0.003).
Superior-posterior coverage of the femoral head by the posterior acetabular wall was insufficient in patients who sustained hip posterior dislocation or subluxation during sports activities.
髋臼前倾角减小以及股骨头后髋臼覆盖不足被认为是与运动相关的后髋关节脱位或半脱位的主要原因。本研究旨在检查21例在体育活动中发生后髋关节脱位或半脱位患者的股骨头后髋臼覆盖情况。
在这些患者的正常侧，在三维计算机断层扫描（3D-CT）图像上描绘髋臼的前后缘。检查包括交叉征和后壁征在内的放射学征象。在受伤髋关节的轴向CT图像上确定髋臼后壁的骨折中心水平（FCL），并在正常侧标记该水平。通过测量FCL处髋臼前后缘之间的水平距离（后-前[P-A]指数）来测量股骨头被髋臼前后缘覆盖的差异。使用正常侧的轴向CT图像在股骨头和FCL处测量髋臼前倾角。使用3D-CT测量正常侧髋臼后壁对股骨头的覆盖面积（面积覆盖率）。
在3D-CT图像中，交叉征和后壁征分别在14例和10例患者中呈阳性。FCL均匀分布在髋臼后壁的近端一半。7例患者的P-A指数≤0，且交叉征均为阳性。这些患者的髋臼前缘相对突出。髋臼前倾角在FCL处低于股骨头中心处（<0.001）。髋臼后壁近端一半区域的覆盖率明显小于整个区域的覆盖率（=0.003）。
在体育活动中发生髋关节后脱位或半脱位的患者中，髋臼后壁对股骨头的上后覆盖不足。
