In healthy bone, up and down are in balance. This is disturbed in the Paget's disease. Many patients are symptom free, others have different symptoms. Paget's disease is named after its first describer, the British physician Sir James Paget. It is also referred to as "Paget's Disease of the Bone" (to distinguish it from Paget's carcinoma, "Paget's Disease of the Breast").
The term osteodystrophia deformans provides a suitable description of the disease: Osteodystrophy refers to a pathological bone remodeling that results in a diminished bone quality, deformans stands for "defacing" as a possible consequence of the disorder.
How is this disease and who is affected?
The cause is still unclear. However, there is evidence that it could be caused by viruses (especially measles viruses) disorder that only becomes noticeable years or decades after the infection (slow virus infection). Since the disease occurs familial and geographically frequent, there is probably also a hereditary tendency.
The bone-graft cells (osteoclasts) necessary for the transformation of the bone are more active than in healthy ones, whereby increased bone tissue is degraded. The body tries to compensate for this accelerated degradation by a precipitous build-up (by means of osteoblasts), which, however, leads to the newly formed bone being of inferior quality.
The result of this increased build-up and build-up are bone thickening and irregularities, bending and reduced load capacity of the skeleton. Most affected are men over 40-50 years, the incidence is 50 to 300 cases per 100, 000 inhabitants. Although Paget's disease is rare, it is still the second most common bone disease after osteoporosis.
How is the disease expressed?
Many sufferers have no or hardly any complaints, so that the diagnosis is often coincidentally made on an X-ray taken for a different reason. If symptoms do occur, they mainly affect areas in which the bones are heavily loaded: lumbar spine, pelvis and legs, possibly also skulls, collarbones and upper arms.
- The increasing deformations may be visible from the outside (for example, saber-shaped bending of the tibia, crooked posture, facial changes (the hat suddenly becomes too small).
- It can - mostly diffuse, pulling - pain in the places of reconstruction (especially at night) occur - especially common are back pain. As a result of the changes, the adjacent joints are increasingly stressed, which increasingly leads to discomfort there as well.
- Spontaneous fractures, severe headaches, deafness and attacks of vertigo (due to deformation of the bone in the inner ear) and nerve paralysis (for example, because deformed vertebrae press the nerve canal) are other possible consequences.
- Due to the increased bone loss calcium is increasingly excreted, which can lead to kidney stones.
- Rare late complication (about 1% of cases) is a malignant bone tumor (osteosarcoma).