Association between US and MRI scores and correlations with urinary C-terminal telopeptide Type II collagen levels for early detection of hemophilic arthropathy of the knee

Assessment of knee hemophilic arthropathy (HA) requires objective measures. There is no consensus on a preferable ultrasonography (US) scoring system, whereas a reliable scoring system for magnetic resonance imaging (MRI) was developed by the International Prophylaxis Study Group of the World Federation of Hemophilia (IPSG-WFH). In this crosssectional study, a new US scoring system for early detection of knee HA was developed based on 25 peer-reviewed articles published between 1999 and 2015; furthermore, its associations with the MRI scoring system and urinary C-terminal telopeptide type II collagen (CTX-II) levels were investigated. In total, 27 children with severe hemophilia A were recruited. Early HA was confirmed using radiography as Arnold-Hilgartner stages 0-II. Knee MRI and US were scored using the MRI IPSG-WFH and new US scoring systems; urinary CTX-II levels were measured using enzyme-linked immunosorbent assay. Correlations were identified using Spearman test. The US scoring system included joint effusion, synovial hypertrophy and hypervascularization on power Doppler US, hemosiderin deposition, and cartilage damage. The US and MRI scores showed a moderate correlation; the US score and urinary CTX-II levels showed no correlation. The new US score can be used as an alternative to MRI for assessing early-stage kne HA.