Answer
In 1868, the physician Volkmann defined the role of hemorrhage in the pathogenesis of the articular findings in hemophilia. [18] People with one of these bleeding disorders are prone to have recurrent episodes of hemorrhage into the joints. [3] Acute bleeding increases the pressure in the synovial cavity and bone marrow, which possibly leads osteonecrosis or a pseudotumoral mass. Intra-articular bleeding produces a direct chemical effect on the synovium, cartilage, and bone. Over time, the blood becomes deposited in the form of hemosiderin in these tissues. Recurrent hyperemia of the joint in the growing child causes juxta-articular osteoporosis and overgrowth of the epiphysis.
Roosendaal and Lafeber found that the articular cartilage is sensitive to the presence of blood and that damage may occur to the cartilage independent of the synovial changes caused by bleeding. [4] However, practically speaking, the imaging changes that appear first are effusion and synovial proliferation. Damage to the bone and articular cartilage appears later.
Bleeding into target joints (the joints that are most commonly affected with repetitive bleeding in an individual patient) starts before the age of 2 years and persists into adolescence. In some patients, bleeding continues into adulthood, even affecting new target joints after age 30 years; however, this occurrence is unusual. The late sequelae of joint hemorrhage appear in adolescence or adulthood as a joint deformity, contracture, and/or degenerative arthritis.
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Knee radiograph in a 37-year-old man with moderate factor IX hemophilia. This image shows bony excrescence on the lateral side of the femur is a hemophilic pseudotumor.
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Radiograph of the lower extremity of the 3-year-old daughter of the patient in the previous image. This image shows talar tilt. The girl not only inherited 1 diseased X chromosome with mild factor IX hemophilia from her father, but she also has Turner (XO) syndrome. The child's only X chromosome had the hemophilia gene.
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Magnetic resonance image from a patient with hemophilia. This image shows dark, synovial masses that erode the cartilage and produce subchondral cysts (arrows).
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Anteroposterior radiograph from a patient with hemophilia. This image demonstrates hemarthrosis with hemosiderin deposition. Note the irregularity of the articular surfaces and the presence of subchondral sclerosis with cysts. Image courtesy of Javier Beltran, MD.
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Lateral radiograph from the same patient as in the previous image. This image shows a large hemarthrosis that is distending the suprapatellar recess. Image courtesy of Javier Beltran, MD.
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Axial gradient-echo magnetic resonance image from a patient with hemophilia. This image demonstrates hemosiderin deposition in the synovium as hypointense material that outlines the joint capsule. Image courtesy of Javier Beltran, MD.
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Radiograph in a patient with hemophilia. This image depicts a pseudotumor that is deforming the cortex of the femur (arrow). Other ossified masses in the soft tissues (arrowheads) are probably soft-tissue pseudotumors.
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Sagittal magnetic resonance image of the ankle joint in a patient with hemophilia. This image shows extension of abnormal joint fluid from the ankle joint into the subtalar joint. Note the dark hemosiderin posterior to the subtalar fluid (arrow).
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Computed tomography scan of the pelvis in a patient with hemophilia. This image demonstrates a giant pseudotumor (a large expansile lytic lesion that involves the right iliac bone and extends into the sacrum, with inhomogeneous internal attenuation). Image courtesy of Javier Beltran, MD.
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Axial T2-weighted magnetic resonance image of the pelvis. This image demonstrates a large pseudotumor of the pelvis with sacral extension. Image courtesy of Javier Beltran, MD.
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Lateral elbow radiograph in a patient with hemophilia. This image shows an opaque joint effusion due to the presence of iron in the synovium (arrows).
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Radiograph of the ankle in a 20-year-old patient with hemophilia. This image shows the development of osteonecrosis (arrow) in the talar dome.
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Sagittal T2-weighted magnetic resonance image of the lower extremity in a patient with hemophilia. This image demonstrates hemosiderin-laden synovium with low signal intensity that outlines the capsule of the tibiotalar joint. Image courtesy of Javier Beltran, MD.
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Radiograph of the shoulder of a 35-year-old man with hemophilia. This image shows advanced degenerative joint disease. The infiltrate in the lung is due to a fungal infection as a complication of the patient's positive human immunodeficiency virus (HIV) status.
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Radiograph of the leg in a patient with hemophilia. This image depicts stage III joint disease, as determined by the Arnold-Hilgartner classification.
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Radiograph of the leg in a patient with hemophilia. This image depicts stage IV joint disease, as determined by the Arnold-Hilgartner classification.
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Coronal T2-weighted magnetic resonance image of the knee in a patient with hemophilia. This image demonstrates pseudotumor of the knee, a lytic lesion in the lateral femoral condyle, as well as the characteristic manifestations of hemosiderin deposition in the knee joint and the subchondral cystic changes in the medial femoral condyle. Image courtesy of Javier Beltran, MD.
