Magnetic resonance imaging and ultrasound evaluation of “healthy” joints in young subjects with severe haemophilia A

Summary Magnetic resonance imaging ( MRI ) and ultrasonography ( US ) are increasingly used in haemophilia A ( HA ) to detect early joint changes. A total of 40 clinically asymptomatic joints, never involved by bleeding events [“healthy joints” ( HJ )], were evaluated by MRI and, in parallel, by US in 20 young subjects with severe HA (22.45 ± 2.72 years old; no history of arthritides, of viral infections or of inhibitors against factor VIII ). The same joints were evaluated in 20 matched non‐haemophilic (no‐ HA ) subjects (mean age 23.90 ± 2.31 years, P  = 0.078 vs. HA subjects). US images were obtained with specific probe positions according to validated procedures. A validated US score and progressive (P‐ MRI ) and additive (A‐ MRI ) MRI scores were employed for data collection and analysis. The US score was higher in HA than in no‐ HA subjects (3.40 ± 1.72 vs. 0.80 ± 1.10, P  < 0.001). Taking into account only moderate/severe alterations, joint effusion was found in 55% of HA and in 5% of no‐ HA joints ( P  < 0.001); synovial hypertrophy was found in 20% of HA and in none of the no‐ HA joints; cartilage erosion was found in 30% of HA and in none of no‐ HA joints. MRI examinations confirmed these findings and the US score correlated with the A‐ MRI ( r  = 0.732, P  < 0.001) and with the P‐ MRI ( r  = 0.598, P  < 0.001) scores. MRI and US data significantly correlated as to effusion ( r  = 0.819, P  = 0.002), synovial hypertrophy ( r  = 0.633, P  = 0.036) and cartilage erosion ( r  = 0.734, P  = 0.010). Despite inherent limitations, joint US examination identified subclinical abnormalities of HJ in young subjects with severe HA .