Deep Kamal, Prabhakara Anjan, Mohan Diwakar, Mahajan Vivek, Sameer Mohamed
Department of Orthopaedics, Golden Jubilee National Hospital, Clydebank, Glasgow, UK.
Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
Arthroplast Today. 2020 Dec 21;7:1-6. doi: 10.1016/j.artd.2020.11.018. eCollection 2021 Feb.
Transverse acetabular ligament (TAL) is a 3-dimensional structure which cannot be defined by a single plane. Therefore, we aimed at describing the orientation of different parts of TAL with respect to anterior pelvic plane (APP) and correlate it with gender, body mass index (BMI), and Lewinnek's safe zone.
A total of 109 consecutive patients undergoing imageless navigated THA were prospectively studied. Computer navigation was used as the measurement tool. APP was registered for navigation. After excision of osteophytes, a trial component matching the size of unreamed acetabular cavity was aligned with acetabular rim, outer and inner margins, and middle of TAL to record cup orientation with computer tracker.
Ninety-nine patients (41 males and 58 females, mean BMI of 28.8kg/m) were studied after applying exclusion criteria. Mean acetabular inclination was 55.15°, 53.00°, 47.70°, and 42.60° respectively, for acetabular rim, outer, middle, and inner margins of the TAL. Corresponding mean acetabular anteversion was 6.63°, 7.41°, 11.23° and 14.90°respectively. Overall, 17.17%, 28.28%, 47.47% and 71.71% of cup orientation corresponding to acetabular rim, outer, middle, and inner margin of TAL respectively, were within Lewinnek's safe zone. No association was established between BMI and acetabular orientation. Males had overall lesser anteversion than females.
We describe orientation of outer, middle, and inner margins of TAL, as reference planes for TAL, in relation to APP. The anteversion differs significantly with gender. A knowledge about these will assist surgeon in component placement during THA, with inner margin of TAL providing the best chance of orientation out of the studied landmarks.
髋臼横韧带（TAL）是一种三维结构，无法用单一平面来界定。因此，我们旨在描述TAL不同部分相对于骨盆前平面（APP）的方向，并将其与性别、体重指数（BMI）以及Lewinnek安全区相关联。
对109例连续接受无图像导航全髋关节置换术（THA）的患者进行前瞻性研究。使用计算机导航作为测量工具。注册APP用于导航。切除骨赘后，将与未扩髓髋臼腔大小匹配的试验假体与髋臼边缘、TAL的外缘、内缘和中部对齐，用计算机跟踪器记录髋臼假体的方向。
应用排除标准后，对99例患者（41例男性和58例女性，平均BMI为28.8kg/m）进行了研究。TAL髋臼边缘、外缘、中部和内缘的平均髋臼倾斜度分别为55.15°、53.00°、47.70°和42.60°。相应的平均髋臼前倾角分别为6.63°、7.41°、11.23°和14.90°。总体而言，分别对应TAL髋臼边缘、外缘、中部和内缘的髋臼假体方向在Lewinnek安全区内的比例为17.17%、28.28%、47.47%和71.71%。未发现BMI与髋臼方向之间存在关联。男性的总体前倾角小于女性。
我们描述了TAL外缘、中部和内缘相对于APP的方向，作为TAL的参考平面。前倾角在性别上有显著差异。了解这些知识将有助于外科医生在THA手术中进行假体放置，在所研究的标志点中，TAL的内缘提供了最佳的定向机会。
