Any infection in and around a replaced joint is called Periprosthetic Joint Infection (PJI). Just like any other infection in the body, PJI occurs when body immunity is low. It is extremely uncommon to have a joint infection. The lifetime incidence of infection is less than 1 to 2%. 

Infections anywhere in the body can be prevented by maintaining good general health. Thus, one should always maintain good hygiene in the operating area, and a good control of diabetes also helps. People with dental or urological infections are more prone to PJI. If you are undergoing a dental or urological procedure, then kindly inform your treating doctor about the replaced joint in your body. If you are planning a joint replacement, then you should at least wait for 3 to 4 weeks after the dental/urological procedure. If you suspect PJI, consult an experienced joint replacement expert at the earliest. 

What is Periprosthetic Joint Infection?

Unlike infections in any other body part, PJIs are usually local infections. They are almost always never life-threatening, and they are usually not accompanied by fever. Usually, patients come with the complaint that the joint, which was working well for years, has started to hurt. There will also be stiffness of the joint.  However, the pain and stiffness of the replaced joint do not always mean it is infected. It would be worthwhile to seek an opinion from a joint replacement expert who would be able to rule out infection for you based on clinical, radiological, and lab parameters. 

Types of Knee Infection

Different types of knee infections involve:

• Septic Joint: This type of infection occurs when the septic enters the knee joint area where immune defence fluid is present.
• After-Surgery Infection: An infection can be developed during the surgical procedure. These are troublesome and usually occur after knee reconstructive surgery.
• Bursal Infection: This particular infection causes swelling over the top of the knee, which causes swelling, redness, and pain in the kneecap.
• Cellulitis: In this case, the infection enters several layers of skin, causing abnormal swelling and pain in the leg.

Symptoms of Infection in Knee Joint

Do not neglect even the smallest of pain or irritation in any part of your body; it can become excessive if not treated in time. The knee is a sensitive area, and replacement surgery can lead to infections.  Infection in knee joint symptoms include:

• Pain in different locations
• Redness
• Excessive Swelling of the knee
• Knee stiffness 

The infection can occur for different reasons, a prominent one being knee replacement surgery. Depending on the severity of the infection, there are numerous ways to cure it, including surgical cleaning, removal of implants, antibiotics, and more.

Treatment for Knee Infection

Knee replacement surgery is the best method for treating severe knee problems. It relieves pain and enables patients to resume various activities. However, it includes certain risks of knee replacement infection, which can be pretty serious. Early infections are curable with a surgical cleaning followed by antibiotic treatment. When the infection exceeds six weeks from the time of surgery, it requires more aggressive treatment, including the removal of replacement implants.

• If diagnosed early, PJI can be treated without removing the existing implants. These patients undergo DIAR (debridement, antibiotics, and implant retention). The key to the success of DIAR is that you reach your joint replacement specialist in time. The earlier that DIAR is done, the better the results and patients can expect normal joint function.
• For patients with chronic infections or those not responding to other treatment measures, two-stage revision is the gold standard treatment. This procedure is done in two stages, as the name indicates, and it gives almost 100 Percent cure with almost no risk of re-infection. In the first stage, we first remove all of the infection from the knee and place a Mobile Antibiotic Spacer in the knee joint. Patients are able to walk and do all their personal activities on the mobile spacer. When we are sure that the infection is cured, we place a revision implant in the knee.
• One-stage revision for PJI is suitable for a carefully selected group of patients only. In this procedure, we remove the infection from the knee and perform revision with the actual knee implant in one sitting. This cures the patient in one sitting and avoids additional surgery.
• Knee stiffness is a common problem, especially among the elderly. It requires a dedicated exercise routine, rest to reduce repetitive strain, ice or heat compressing (as suggested by a professional), and elevation. If you are still unable to cure the stiffness, it’s better to consult the doctor for knee stiffness treatment.

Conclusion

Knee health is a critical aspect of overall well-being, and understanding the different conditions that can affect your knees is essential for seeking the right treatment. These infections require specialised care and prompt treatment to ensure the best outcomes. For those facing severe knee problems or complications following surgery, infection may be a possible reason. Thus, understanding the types of infections, their symptoms, and the available treatment can be crucial. With the right medical guidance and a personalised treatment plan, you can manage your knee health effectively and regain your mobility and comfort.

Whether you are dealing with knee pain, stiffness, or infections, consulting an experienced orthopaedic specialist can help you find relief and improve your quality of life.