Direct MR arthrography of the hip joint: anterior approach without imaging guidance.

PURPOSE: The purpose of this study is to describe the anterior injection approach, with anatomical landmark guidance, for direct MR arthrography (dMRA) of the hip joint, and to evaluate the effectiveness in joint distension and the security of the technique. MATERIAL AND METHODS: Retrospective review of hip dMRAs was conducted on patients with suspected intra-articular pathology from two MR outpatient centers, performed by two radiologists with 25 and 5 years of experience, respectively. The analysis included assessing the presence of intra-articular contrast material (gadolinium-based solution), the number of injections performed, the degree of joint distension, and the degree of contrast extravasation. A multi-variant analysis was carried out to determine if the procedure success depend on any of the demographic variants or on the radiologist experience. Additionally, the presence of immediate and medium-term post-puncture complications was evaluated. RESULTS: One hundred patients with 104 hip dMRA were included; 60 were men, with mean age of 38 years (16-63 years). Contrast material was successfully introduced intra-articularly in 100% of patients, being necessary a second puncture only in 6% of procedures. The capsular distension was considered optimal for diagnosis in 97% of cases. Different degrees of contrast extravasation were found in 30% of dMRA. There was no statistically significant relationship observed between patient variables and the performance of dMRA, nor did it show any correlation with the experience of the radiologists. No puncture-derived complications were found. CONCLUSION: Hip dMRA through anterior injection guided by anatomical references is an effective and safe alternative for patients with suspected intra-articular pathology.