The transverse acetabular ligament may be used to align the acetabular cup in total hip arthroplasty

Accurate positioning of the acetabular component in total hip arthroplasty is essential to minimise the risk of dislocation and preserve the range of movement of the hip. It also affects polyethylene wear and the rate of osteolysis. Although there are many tools available to the surgeon to aid placement of the acetabular component, errors still occur, especially in version. We conducted a study of 14 cadaveric hips to investigate whether the transverse acetabular ligament can be used to align implanted cups with the correct degree of anteversion. Radiographic measurement revealed that all of the implanted cups were found to lie within the ‘safe zone’ for anteversion, when aligned with the ligament.