Effects of hemophilia on articulations of children and adults.

The majority of bleeding episodes in hemophilic patients occur within the joints. Of these hemarthroses, the knees, elbows, and ankles account for almost 80%. Should the bleeding persist, the synovium starts to hypertrophy and a vicious cycle of chronic synovitis develops, leading to joint destruction. In immature articulation, synovitis causes hypertrophy of the epiphyseal growth plates and significant structural deficiencies may rapidly develop. This stimulus to the growth plates results in bone hypertrophy, leg length discrepancy, and angular deformities. In mature articulation, hemophilia has a major detrimental effect on the joint cartilage. As it progressively exacerbates, joint function deteriorates. Loss of joint space is the most important radiographic finding related to range of motion. As the synovium becomes increasingly scarred, there is gradual conversion from friable hyperemic tissue to fibrotic scar tissue. This process is the natural course of hemophilic arthropathy. A phenomenon in adult hemophilic patients is that their joints, which radiographically appear severely destroyed, seem to function reasonably well for many years.