The acetabular transverse ligament bridges the acetabular notch at the inferior acetabular rim, converting the notch into a foramen through which the acetabular branch of the medial femoral circumflex artery and the ligamentum teres pass to reach the femoral head. It is a continuation of the acetabular labrum that spans the non-articular notch region, completing the ring of the labrum.
Converts the acetabular notch into a foramen for the passage of the ligamentum teres and acetabular vessels, stabilises the inferior labral ring, and provides a rigid arch preventing inferior labral deformation under load.
The acetabular transverse ligament is the reference landmark in hip arthroscopy for ligamentum teres identification, cotyloid fossa assessment, and labral tear classification (tears extending to the transverse ligament are circumferential). In hip arthroplasty, the transverse ligament is used to judge acetabular component position: the component inferior edge should be flush with the transverse ligament to achieve the correct inferior placement. Transverse ligament injury in hip dislocation contributes to the pattern of acetabular labral tear associated with the dislocation force.
The acetabular transverse ligament at the inferior acetabular notch provides an intraoperative bony and soft tissue landmark for acetabular cup inferior placement in total hip arthroplasty; placing the inferior cup edge at the transverse ligament level reduces the risk of superior overmedialisation and achieves the intended anatomical leg length without requiring intraoperative radiograph.
