Prosthetic joint infection

Joint replacement is a safe and effective surgery that improves patients' quality of life by providing symptomatic relief, improving mobility, and restoring joint function.

The most common reason for joint replacement surgery is osteoarthritis, a degenerative condition that affects the cartilage in the joint, leading to pain, stiffness, and decreased mobility.

Other conditions that may require joint replacement surgery include rheumatoid arthritis, joint injury or trauma, and avascular necrosis (loss of blood flow to the bone).

Prosthetic joints are artificial devices that replace a damaged or diseased joint. There are two main types of prosthetic joints: total joint replacements, which replace the entire joint, and partial joint replacements, which replace only the damaged or diseased parts of the joint.

Prosthetic joints are typically made from metal, plastic, or ceramic materials and are designed to mimic the function of a natural joint. They are attached to the bones with cement or other fixation devices and are usually expected to last for many years, although the lifespan of a prosthetic joint can vary depending on factors such as the patient's age, activity level, and overall health.

A small percentage of people with replacement joints are at risk of developing an infection. A prosthetic joint infection is an infection that occurs in a joint replacement, such as a hip or knee replacement. This type of infection can occur within the first few months after surgery or even years late.

Causes of prosthetic joint infection

1. Bacterial contamination during surgery: This can be caused by improper sterilization of equipment or poor surgical technique.
2. Pre-existing infection: If a patient has a pre-existing infection, such as a urinary tract infection, it can spread to the prosthetic joint through the bloodstream.
3. Poor wound healing: Poor wound healing can create an environment that is more susceptible to bacterial infection.
4. Immunocompromised: Patients with weakened immune systems, such as those with diabetes or human immunodeficiency virus (HIV), are at a higher risk of developing prosthetic joint infections.
5. Poor oral hygiene: Poor oral hygiene can lead to the growth of bacteria in the mouth, which can travel to the prosthetic joint through the bloodstream.
6. Foreign body reaction: Some patients may have an allergic or hypersensitivity reaction to the implant material, leading to inflammation and infection.
7. Prosthetic loosening: Loosening of the prosthetic joint can create space for bacteria to grow and cause an infection.

Symptoms of prosthetic joint infection

• Warmth, tenderness, and redness at the incision site
• Wound drainage
• Joint effusion
• Fever
• Persistent joint pain
• Fatigue

If you experience any of these symptoms after joint replacement surgery, it is important to contact your doctor right away.

Diagnosis of prosthetic joint infection

Diagnosing prosthetic joint infections can be challenging, as the symptoms may be nonspecific and can mimic other conditions. Patients with relevant signs and symptoms of infection and a joint prosthesis should be suspected of prosthetic joint infection.

Your doctor would first question your general health and symptoms before conducting a thorough physical examination. Diagnosis is made based on your reported symptoms, physical examination, and investigations.

1. Blood tests: Blood tests can help determine if there is an infection present in the body. Your doctor may order tests such as a complete blood count (CBC), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) levels.
2. Imaging tests: Imaging tests such as X-rays, magnetic resonance imaging (MRI), and computed tomography (CT) scans can help detect any changes in the bone or soft tissue around the joint.
3. Aspiration and culture: Your doctor may use a needle to extract fluid from the joint for testing. This fluid is then cultured to determine if there is any bacterial growth. A positive culture indicates the presence of an infection.
4. Biopsy: In some cases, a biopsy may be necessary to confirm the diagnosis of prosthetic joint infection. Your doctor may take a small sample of tissue from around the joint and send it to the lab for testing.

Treatment options for prosthetic joint infection

Prosthetic joint infection can be hard to treat due to the development of biofilm within the joint. When bacteria adhere to the solid surface of an artificial joint, a biofilm forms. The biofilm can function as a shield for some bacteria, making it difficult to detect and destroy them with the body's natural defences or antibiotics.

The treatment of prosthetic joint infection typically involves a combination of surgical intervention and antibiotic therapy.

Surgical intervention

The surgical treatment of prosthetic joint infection may involve one or more of the following procedures:

1. Debridement and retention of prosthesis: This involves the removal of infected tissues around the joint and retention of the original joint implant.
2. Resection arthroplasty with reimplantation: This involves removing the infected implant and replacement with a new implant.
3. Fusion or amputation: In some cases where the infection is severe and cannot be treated with other methods, joint fusion or amputation may be necessary.

Antibiotic therapy

The type of antibiotic and duration of treatment may vary depending on the severity of the infection, the type of bacteria involved, and other factors. Intravenous antibiotics may be given initially, followed by oral antibiotics.

Prevention of prosthetic joint infection

Preventing prosthetic joint infections involves a combination of measures before, during, and after surgery. Here are some steps you can take to help reduce the risk of infection:

1. Antibiotic prophylaxis: Your doctor may prescribe antibiotics before and after surgery to help prevent infection. It is important to take the antibiotics exactly as prescribed and finish the entire treatment course.
2. Post-operative care: After surgery, following your doctor's instructions for caring for your incision site, such as keeping it clean and dry, is essential. Maintaining good personal hygiene is vital to reduce the risk of infection. Avoid activities that may strain the joint.
3. Regular follow-up: Regular follow-up appointments with your doctor to monitor the healing process and identify any signs of infection early.

Make an appointment at Gleneagles Hospitals

If you are experiencing any of the symptoms of prosthetic joint infection, get in touch with us to find out more about our Orthopaedic Services at your nearest Gleneagles Hospital.

Gleneagles Hospital works with orthopaedic specialists to assist patients through diagnosis and treatment. The caring and multidisciplinary team of healthcare professionals are available for consultation and to provide the best care.