Ara Kassarjian MD, Presenter: Consultant, Arthrosurface, Inc Consultant, Johnson & Johnson

Jenny Teresa Bencardino MD, Abstract Co-Author: Nothing to Disclose

Eva Llopis MD, Abstract Co-Author: Nothing to Disclose

Richard B. Schwartz MD, Abstract Co-Author: Nothing to Disclose

To demonstrate the prevalence of communication between the hip joint and the obturator externus bursa at hip MR arthrography.

Following institutional review board approval, 110 hip MR arthrograms were retrospectively reviewed by 2 musculoskeletal radiologists. The presence or absence of communication between the hip joint and the obturator externus bursa was recorded. Communication between the hip joint and the obturator externus bursa was defined as gadolinium entering the obturator externus bursa. The status of the acetabular labrum, articular cartilage, and presence or absence of hip plicae were recorded.

110 hip arthrograms in 108 subjects were independently reviewed by 2 musculoskeletal radiologists. Discrepancies were resolved by consensus. The obturator externus bursa was seen to communicate with the hip joint in 7 of 110 hip MR arthrograms. Of these, 3 were men and 4 were women. The age range was 16-54 years old with a mean age of 33 years. All seven patients had labral tears. Five of the seven had mild degenerative changes including cartilage thinning/defects and subchondral marrow changes. In all seven patients, labral plica, ligamentous plica, and femoral neck plica were visible.

The obturator externus bursa can be seen to communicate with the hip joint in 6% of hip MR arthrograms. Associated intra-articular lesions are common.

This study shows that the obturator externus bursa communicates with the hip joint in 6% of hip MR arthrograms.

Kassarjian, A, Bencardino, J, Llopis, E, Schwartz, R, Obturator Externus Bursa: Prevalence of Communication with the Hip Joint in 110 Consecutive Hip MR Arthrograms.  Radiological Society of North America 2008 Scientific Assembly and Annual Meeting, February 18 - February 20, 2008 ,Chicago IL. http://archive.rsna.org/2008/6016041.html