Value of magnetic resonance imaging for the diagnosis and follow-up of haemophilic arthropathy.

An orthopaedic assessment of the joint status of seven severe haemophiliacs (mean age 12.5 y - range 8.9-15.5) on prophylactic treatment (PT) by magnetic resonance imaging (MRI) and physical examination was carried out. Median duration of PT of these patients was 84 months (range 32-107). A locally designed MRI joint score considering seven parameters (1 - joint effusion, 2 - synovial membrane thickening, 3 - haemosiderin deposits, 4 - joint cartilage injury, 5 - subchondral bone erosion, 6 - subchondral bone cysts, 7 - osteonecrosis) was used (maximum score = 13 points). MRI scans were performed in 17 joints (nine ankles, seven knees and one elbow): mean MRI scores for the affected joints was 5.1. A poor consistency between physical examination and MRI findings or the real extent of joint damage was found (Cohen kappa index 0.320). MRI is a precise non-invasive tool for the assessment of early joint cartilage and synovium pathological changes still undetectable by physical examination or conventional X-rays in the haemophilic setting.