Christian W. A. Pfirrmann MD, Presenter: Nothing to Disclose

Bernard Mengiardi MD, Abstract Co-Author: Nothing to Disclose

Claudio Dora MD, Abstract Co-Author: Nothing to Disclose

Marco Zanetti MD, Abstract Co-Author: Nothing to Disclose

Juerg Hodler MD, Abstract Co-Author: Nothing to Disclose

To assess characteristic MR arthrography findings in patients with femoroacetabular impingement syndrome.

MR arthrography of 50 consecutive patients with surgically proven femoroacetabular impingement were analyzed by two musculoskeletal radiologists for labral abnormalities, cartilage lesions, femoral waist deficiency and osseous abnormalities. The femoral waist as well as the acetabular depth were quantitatively assessed.

In 70% of patients the main cause of femoroacetabular impingement was femoral, in 30% of patients the main cause was acetabular. Anterior labral lesions were seen in almost all (98%) patients (tears 58%, degeneration 40%). Superior labral lesions were found in 96% (tear 54%, degeneration 41%). Posterior labral lesions were seen in 38% (10% tear, 28% degeneration) posterior inferior lesion were rare: 10% (tear 2%, degeneration 8 %) 82% of patients had an anterior waist deficiency, 34 % a lateral femoral waist deficiency. Os acetabuli (22%) and herniation pit (26%) were quite frequently seen. In 16% an acetabular retroversion and in 18% a deep acetabulum was seen. Anterior acetabular cartilage lesions were seen in 68%/18% (labral-acetabular junction/ medial articular cartilage). Superior cartilage lesions were seen in 82%/42%, posterior lesion in 34%/12%, and postero-inferior lesions in 24%/24%.

Characteristic MR arthrography findings of femoroacetabular impingement are anterior femoral waist deficiency, anterior and superior labral lesions and cartilage lesions at the labral-acetabular junction. Herniation pits and Os acetabuli are common findings in patients with femoroacetabular impingement.

Pfirrmann, C, Mengiardi, B, Dora, C, Zanetti, M, Hodler, J, MR Arthrography in Femoroacetabular Impingement Syndrome: Characteristic Findings in 50 Patients with Surgical Correlation.  Radiological Society of North America 2004 Scientific Assembly and Annual Meeting, November 28 - December 3, 2004 ,Chicago IL. http://archive.rsna.org/2004/4412810.html