CT Reveals a High Incidence of Osseous Abnormalities in Hips with Labral Tears

Abstract

Background Acetabular labral tears are being diagnosed with increasing frequency and there is a growing consensus that these tears rarely occur in the absence of osseous abnormalities. Questions/purposes We therefore determined the presence of structural abnormalities in patients with acetabular labral tears using a standardized CT protocol. Methods We evaluated 135 consecutive patients with labral tears diagnosed by MRI with CT scans of the symptomatic hip. The CT scans were evaluated in a standardized fashion to determine acetabular and femoral pathomorphologic features. Acetabular evaluation included version measurements and anterior and lateral center-edge angles. Femoral parameters evaluated included version, alpha angle, and neck-shaft angle. Results One hundred twenty-two (90%) of the 135 hips had structural abnormalities. One hundred two (76%) had an alpha angle greater than 50°, 18 (13%) had femoral version less than 5°, 22 (16%) had femoral version greater than 258, and five (4%) had coxa valga. Fifty-eight (43%) patients had acetabular retroversion and five (4%) had a lateral center-edge angle less than 208. Of the 58 patients with acetabular retroversion, 23 had isolated cranial retroversion, 12 had isolated central retroversion, and 23 had combined cranial and central retroversion. Sixty-seven of the 121 hips (55%) with bony abnormalities had a combination of abnormalities. Conclusions Ninety percent of patients with labral tears had structural abnormalities seen on CT scans. These structural abnormalities frequently occur in combination, and understanding these underlying morphologic features of the hip can help guide treatment.

Reliability of Overcoverage Parameters With Varying Morphologic Pincer Features: Comparison of EOS® and Radiography

“…femoral side, with resultant loss of head-neck offset (cam morphologic features), and/or overcoverage on the acetabular side (pincer morphologic features), leading to subsequent cartilage and labral degeneration [7,9,10,13,27]. Despite advances in three-dimensional (3-D) imaging (CT and MRI), quantification of pincer severity (acetabular overcoverage) continues to be based on biplanar radiographic imaging [16,23,29].…”

Case Reports: Anteroinferior Acetabular Rim Damage Due to Femoroacetabular Impingement

“…structural factors. In up to 1 . 3 of patients with FAI, the pathoanatomy causing the impingement can only be visualized on radial MRI sequences or three-dimensional (3-D) CT reconstructions [6,7,29]. For some patients, 3-D simulations of hip motion are also helpful for elucidating the probable cause of the labral damage [3,4,16].…”

CORR Insights®: Can Femoral Rotation Be Localized and Quantified Using Standard CT Measures?

“…Speakers at conferences state that there is less anterior coverage in the presence of increased femoral anteversion. Additionally, increased femoral anteversion angles have been associated with bigger labral tears observed at hip arthroscopy [4,15].…”