What is bone edema of the knee?
Bone edema is the accumulation of fluid within the bone that can occur, for example, as a result of injury or bone disease. The bones of the knee joint are among the most common areas where bone edema can occur. However, it is not a uniform clinical picture, but rather a description of conspicuous accumulations of water in the bone, if these are detected by means of an imaging procedure. Possible complaints that can occur with bone edema in the knee are pain and a restriction of joint movement. There may also be no symptoms at all and the bone edema is only detected by chance during an examination.
Causes
Bone edema in the knee is not a defined disease, but a pathological change in the bone due to water retention, which can have a variety of causes. A common group of causes are injuries to the knee, for example, while playing soccer or other sports. The destruction of small elements of the bone architecture results in cavities that fill with water and thus cause bone edema in the knee.
Likewise, inadequate blood circulation in the bone can be the cause of bone damage and the resulting bone edema. In addition to these most common triggers, side effects of drugs or metabolic diseases are other possible causes of bone edema in the knee. In general, the knee as the largest movable joint in the body is more frequently affected by bone edema than most other parts of the body due to the high stress to which it is exposed.
An accident is one of the most common causes of bone edema in the knee. If the bones are injured, for example in sports or a traffic accident, small damage to the bone structure often occurs. As a result, small cavities can form.
This is where tissue water or blood usually collects. In an otherwise healthy person with normal blood circulation in the knee, the body will repair the damage to the bone in the following days and weeks. The destroyed bone substance is rebuilt and the fluid storage responsible for the bone edema is reabsorbed.
Special treatment is therefore usually not necessary in cases of bone edema in the knee as a result of an accident. Only if a bone fracture occurs or the symptoms do not subside is specific treatment necessary. In the case of knee arthrosis, i.e. wear and tear of the knee joint, fluid may be stored in the bone due to damage to the joint cartilage.
This is then also known as reactive bone edema of the knee, as it develops as a result of a pre-existing disease of the joint. In contrast to many other causes of bone edema, the pathological changes due to knee osteoarthritis can already be detected by a normal X-ray of the joint. The treatment of bone edema in knee osteoarthritis is usually a combination of drug treatment and exercise, for example through physiotherapy. If the osteoarthritis is severe, surgical joint replacement should be considered.
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