Definition
Joint swelling can occur in various joints. The knee is very often affected. A swelling of the knee joint means that the knee is thicker.
If it occurs unilaterally, one has a good comparison. A swelling can indicate an injury or an inflammatory process in the joint space. Frequently, other complaints such as redness, overheating and also pain occur.
A joint swelling can occur for various reasons. It can be unilateral or symmetrical on both knees. The knee joint is often subjected to a great deal of stress.
This is one of the most common causes of swelling. Prolonged standing or even sporting activities that place enormous strain on the knee joint, such as running, jumping and heavy lifting, can lead to overloading of the bony structures but also of the surrounding soft tissues such as tendons and ligaments. Too much stress can cause small lesions and tears in the cartilage, but also in the soft tissue structures, especially the tendons.
This results in an inflammatory reaction. As a result, more synovial fluid accumulates in the joint space, which can be so large that a swelling of the knee is even visible from the outside. Similar processes are also caused by different diseases.
These include particularly chronic inflammatory diseases such as rheumatoid arthritis. In this disease, the inflammation of the joint is autoimmune. This means that the immune system attacks the body’s own structures, triggering various processes, including inflammation.
In addition to autoimmune diseases, various injuries such as torn ligaments, an inflammation of the bursa (bursitis), bone fractures or even wear and tear in the context of osteoporosis can cause swelling in the knee. Another cause can be reactive arthritis. Here, inflammation occurs in various joints after various bacterial infections.
The trigger may have been a previous gastrointestinal disease, a venereal disease or a urinary tract infection. Furthermore, bacteria or viruses that have been carried over can also be responsible for swelling in the knee. The metabolic disease gout also leads to swelling in joints, including the knee.
This is an increased accumulation of uric acid crystals in the joint spaces. In addition to inflammatory reactions, they also lead to unpleasant pain. Borrelia are certain bacteria that can cause various diseases in humans.
They are often found in ticks. Through a tick bite they are transmitted to humans and in some cases can cause an infectious disease called Lyme disease. This infectious disease initially manifests itself with a palm-sized redness around the original tick bite.
Typically, this redness then migrates to other areas of the skin. For this reason, it is also called migratory redness (erythema chronicum migrans). The reddening of the skin usually allows a reliable diagnosis of the infection, as this sign is so typical for Lyme disease.
The disease has a slow progression. Those affected also suffer from headaches, muscle aches, fever appears in the later course and general exhaustion and tiredness. In the further course and if Lyme disease remains untreated for a longer period of time, the bacteria also spread to other organs such as nerves, meninges, heart, eyes, skin and joints. In the joints the bacteria lead to an inflammation, also known as Lyme Arthritis. According to this, a swelling in the knee can also occur in connection with a Borrelia infection.
