Radiographic Diagnosis of Hip Osteoarthritis
Initial Imaging Approach
- Plain radiographs remain the first-line imaging modality for suspected hip osteoarthritis, providing excellent screening for OA features including joint space narrowing, osteophytes, subchondral sclerosis, and cysts, as recommended by the European League Against Rheumatism 2, 3
- The standard radiographic series should include an AP pelvis view and a lateral view of the symptomatic hip, such as a frog-leg lateral or false profile view, according to the American College of Radiology 1, 4
Diagnostic Criteria on Radiographs
- Additional features supporting OA diagnosis include osteophytes, subchondral sclerosis, and subchondral cysts, as stated by the European League Against Rheumatism 2
When Imaging May Not Be Required
- In patients over age 40 with typical OA presentation, clinical diagnosis without imaging is acceptable, as suggested by the European League Against Rheumatism 2, 3, 5
Advanced Imaging Considerations
- MRI without contrast or MR arthrography should be reserved for cases where radiographs are negative or equivocal but clinical suspicion remains high, or when intra-articular pathology beyond OA is suspected, as recommended by the American College of Radiology 1
Optimal Radiographic Technique
- For the AP pelvis view, the hip should be positioned with 15 degrees of internal rotation to optimize visualization, as stated by the American College of Radiology 4