Causes | Patellar Tendon Inflammation

Causes

Basically, an inflammation of the patellar tendon can occur by infectious or non-infectious means. Inflammation due to invading pathogens is relatively rare compared to other causes and usually requires an entry port for the pathogens, for example in the form of a wound. The non-infectious development of patellar tendon inflammation usually has several causes or is based on an interaction of several factors.

The main component, however, is in most cases repeated overuse and/or incorrect loading. In individual cases, however, even short-term overloading, especially in an unheated training state, can lead to patellar tendonitis. In addition, drugs such as some antibiotics (e.g. from the group of so-called fluoroquinolones) can also cause patellar tendon inflammation.

Symptoms

As with any tendon inflammation (tendinitis), patellar tendon inflammation almost always shows some, but rarely all of the classic five signs of inflammation. In addition to pain (dolor), which usually increases significantly under stress, a functional impairment (functio laesa) is to be expected, but swelling (tumor), redness (rubor) or overheating (calor) of the affected area are also possible. In many cases (unless the cause is not a sudden overload or an accident), these signs (symptoms) are insidious, i.e. they are weak at the beginning and then gradually increase in strength.

Often the onset of patellar tendon inflammation is not consciously perceived, since in the early stages of the disease, complete freedom from symptoms can prevail. In addition, there is usually some time between noticing the first signs of the disease and drawing conclusions. If the patient is not immediately spared at the onset of symptoms, a significant increase in pain can be expected.

This pain, which is also the main symptom of the disease, is located below the kneecap (patella) and increases significantly with movement in the knee joint or even heavy strain on the tendon (active leg extension).This is the case, for example, when running up and down stairs, walking downhill or a general exercise of the large thigh muscle (Musculus Quadriceps femoris), but it can also occur at rest and without any stressful influences. In addition, the inflamed region may react more sensitively to external pressure, touch or heat. In the case of a chronic inflammation of the patellar tendon, calcium deposits can also develop, which, when moved, lead to increased friction in the corresponding tendon.

These calcium deposits can also cause crunching noises when the knee is moved. In addition, the affected patient can sometimes feel this crunch himself. In the course of chronification, nodular thickening of the tendon cannot be ruled out.

Furthermore, the tendon may lose tensile strength due to the permanent inflammatory process. In the worst case, a tear (rupture) of the tendon is also possible. Although this is extremely rare, it is favored by the pre-damage of the tendon during its inflammation.