Is the transverse acetabular ligament a reliable cup orientation guide?

Abstract

Background and purpose It is controversial whether the transverse acetabular ligament (TAL) is a reliable guide for determining the cup orientation during total hip arthroplasty (THA). We investigated the variations in TAL anatomy and the TAL-guided cup orientation.Methods 80 hips with osteoarthritis secondary to hip dysplasia (OA) and 80 hips with osteonecrosis of the femoral head (ON) were examined. We compared the anatomical anteversion of TAL and the TAL-guided cup orientation in relation to both disease and gender using 3D reconstruction of computed tomography (CT) images.Results Mean TAL anteversion was 11° (SD 10, range –12 to 35). The OA group (least-square mean 16°, 95% confidence interval (CI): 14–18) had larger anteversion than the ON group (least-square mean 6.2°, CI: 3.8 – 7.5). Females (least-square mean 20°, CI: 17–23) had larger anteversion than males (least-square mean 7.0°, CI: 4.6–9.3) in the OA group, while there were no differences between the sexes in the ON group. When TAL was used for anteversion guidance with the radiographic cup inclination fixed at 40°, 39% of OA hips and 9% of ON hips had more than 10° variance from the target anteversion, which was 15°.Interpretation In ON hips, TAL is a good guide for determining cup orientation during THA, although it is not a reliable guide in hips with OA secondary to dysplasia. This is because TAL orientation has large individual variation and is influenced by disease and gender.

Accuracy of an adjustable patient-specific guide for acetabular alignment in hip replacement surgery (Optihip)

“…[23][24][25][26] Our mechanical device was designed so that it can focus on guiding the inclination angle only, if desired, which simplifies both the planning and the execution. For these cases, only a standard AP radiograph is required.…”

Total hip arthroplasty in patients of post polio residual paralysis: A retrospective case series

“…The transverse acetabular ligament (TAL) was only used as a landmark during cup positioning in the two cases whose acetabula were less distorted. It has been reported that although TAL may be a good guide in hips with normal anatomy, TAL is not a reliable guide in hips with osteoarthritis secondary to dysplasia for determining optimal cup orientation during THA 20. Anterior and posterior stability were evaluated routinely with the trial components.…”

Preoperative Evaluation of Transverse Acetabular Ligament Orientation using CT for Total Hip Arthroplasty

“…Images were rotated to align with the anterior pelvic plane [18]. The line of the superior TAL was established between the posteroinferior and anteroinferior edges of the acetabular rim, as previously reported [11]. The first angle of the TAL for three-dimensional (3D-CT) was measured between the line of the superior edge of the lowest visible vertebra and that of the TAL.…”

“…Archbold et al reported that the transverse acetabular ligament (TAL) and acetabular labrum were useful for determining the anteversion of the acetabular component [7]. TAL has been evaluated as an anatomic landmark for acetabular component orientation [7][8][9][10][11][12][13][14][15][16][17]. The usefulness of TAL as a landmark is still controversial.…”