What imaging confirms the diagnosis of Hip osteoarthritis?

• A. Ultrasound showing joint effusion
• B. X-rays showing degenerative changes.
• C. MRI showing meniscal tear
• D. CT showing femoral head necrosis

Answer: (B)

Plain X-ray of the hip is the imaging test that best confirms hip osteoarthritis because it shows the characteristic degenerative changes in the joint. On radiographs, you look for joint space narrowing from cartilage loss, osteophyte formation at the joint margins, subchondral sclerosis (increased density under the cartilage), and subchondral cysts. These findings together establish the diagnosis and help grade severity (often with Kellgren-Lawrence).

Ultrasound can detect effusion or synovitis but does not reliably confirm OA. MRI can reveal cartilage loss and early bone changes, but it’s not routinely needed to confirm OA and is used when there’s diagnostic doubt or to assess surrounding structures. CT provides detailed bone anatomy but involves more radiation and is not the standard confirmatory test for OA. If imaging suggested something like avascular necrosis or another hip pathology, that would point away from OA.