Associated symptoms

Pain and swelling after knee joint surgery is not uncommon and can occur even in a normal course. However, suddenly occurring swelling, redness or warming of the knee joint should be seen as a warning sign. Caution is also required if wound secretion suddenly emerges in the area of the operation.

If a fever occurs, an examination should be carried out without fail, as this can be a serious inflammation. In the course of the inflammation, flu-like symptoms such as chills, fatigue, headaches and muscle aches can also occur. If dull pain, swelling and a blue-livid coloration of the leg occur, a vascular occlusion of the leg (thrombosis) may be present.

This complication usually occurs shortly after the operation if the leg was immobilized and no adequate preventive measures, such as the administration of blood-thinning medication, were taken. A restriction of movement of the knee joint may also occur. This can be caused by severe swelling or by malpositioning or loosening of the joint.

Diagnosis

To determine the cause of the knee pain, the knee joint is examined. During the inspection, malpositioning, redness and swelling may be noticed. In addition, the passive range of motion of the knee is examined during an inspection, which can also be limited if the knee prosthesis is defective.

An X-ray, CT and scintigraphy can show the joint and possible loosening. A blood test should also be performed, which may indicate an inflammation. Furthermore, if there is a suspected infection of the joint, a puncture of the inflammatory infiltrate should be performed. The obtained puncture can then be examined for bacteria.

Therapy

The treatment depends on the cause of the complaints. Pain that occurs immediately after the operation is treated with painkillers. This should make the patient pain-free so that he or she can perform light exercises.

The pain therapy can be carried out with so-called NSAIDs such as ibuprofen, diclofenac or naproxen. For severe pain, opioids such as fentanyl or morphine can be used. However, the pain should have disappeared as far as possible after the hospital stay.

If the pain persists, a prolonged therapy with medication can be carried out.It is also important for healing after knee surgery to follow a post-operative treatment plan with physiotherapy and training, and to adhere to it consistently. On the one hand, this avoids overloading and on the other hand, a training program is determined that is tailored to the new joint and the patient. If the new knee joint is malaligned or loosened, painkillers can only help to a limited extent, as they do not eliminate the cause.

Therefore, in these cases, the prosthesis must be replaced and thus a new operation must be performed. If there has been an infection in the knee joint, the therapy goal is to eliminate the bacteria causing the inflammation. Antibiotic therapy is important here.

In addition, the joint should be cooled and protected. If a serious infection occurs, the joint must be removed. If a vascular occlusion is the cause of the pain, a therapy with blood thinners must be carried out to make the vessel permeable again.