Contribution of helical computed tomography to the evaluation of early hip osteoarthritis: a study in 18 patients

Objectives. - To show that helical computed tomography arthrograms (HCTA) with multiplanar reformations can document cartilage lesions and their characteristics in patients with suspected hip osteoarthritis and normal or inconclusive hip radiographs. Methods. - We retrospectively reviewed abnormal HCTAs from patients with mechanical hip pain and normal findings on anteroposterior and oblique ("faux profil") radiographs of the pelvis. HCTA in all patients consisted in acquiring 1 mm transverse slices and obtaining coronal and sagittal reformations. Radiographs and HCTAs were read separately by two experienced radiologists, who then worked together to reach a consensus. Results. - We identified 18 patients with abnormal HCTA findings and a full set of imaging studies. Mean age was 47.8 years, and there were 14 women and four men. Acetabular cartilage lesions were found consistently; they were often deep and predominated in the anterosuperior region. A labral fissure was noted in 12 patients. The sagittal and coronal reformations proved more informative than the acquired transverse slices. Interobserver reproducibility was excellent for the HCTA diagnosis of cartilage lesions. Conclusions. - In patients with hip pain and normal radiographs, HCTA can provide a diagnosis of hip osteoarthritis by showing cartilage lesions, which are usually located in the anterosuperior part of the acetabulum. (C) 2005 Elsevier SAS. All rights reserved.