Joint Replacement Infection

Joint replacement infections are a very dangerous surgical complication, particularly knee and hip replacement infections.

These infections are difficult to treat because the bacteria strike the prosthetic itself, which is a metal or porcelain object and not human tissue. Infectious bacteria adhere to the implant, making the implant a hospitable location for infections.

What's worse, fighting infections depends on blood flow for an effective immune system response and also to deliver antibiotics to the area. Artificial implants have no blood supply, which makes joint replacements a safe haven for bacteria.

Even with aggressive antibiotic treatment and surgical cleansing, curing an infection on a joint replacement is often impossible. Many times the only way to cure an infection is to remove the entire implant, treat the infection, and redo the joint replacement.

These infections are rare, occurring in 1% to 2% of patients, but given that joint replacement surgery has become one of the world's most common elective procedures, thousands are affected each year.

Surgical staff now have routine procedures in place to prevent infections. Some steps are known to lower the risk of infection, while some are thought to help but whether they actually do hasn't been proven.

The most common measures:

• Antibiotics before and after surgery. Antibiotics are given within one hour of the start of surgery and continued for a short period following the procedure. Different antibiotics may be used depending on the patient's individual history of infection, allergies to specific medications, and other concerns.
• Short operating time and minimal operating room traffic. Surgical efficiency helps to lower infection risk by limiting the time the joint is exposed. Limiting the number of operating room personnel entering and leaving the room is also thought to decrease risk.
• Use of strict sterilization techniques. Care is taken to ensure the operating site is sterile. Reusable instruments are sterilized in an autoclave and not exposed to any contamination. The implants are packaged to ensure their sterility. Disposable items are sterile and discarded after use.

Most patients have no identifiable cause for developing an infection. Still, some known risk factors include:

• Use of general anesthesia versus spinal anesthesia (epidural).
• Immune deficiencies (e.g. HIV, lymphoma), or immune suppressive treatments like chemotherapy
• Diabetes
• Rheumatoid arthritis
• Obesity
• Smoking

Infection after joint replacement surgery is among the most feared complications of this surgical procedure. If you experience any symptoms, contact your doctor immediately for blood tests and a possible x-ray or MRI to diagnose the problem.