Infected knee replacement- Is it the end of the road?

Jul 25

Knee replacement, which is also known as knee arthroplasty, is an orthopedic surgical procedure to salvage a damaged knee. Some reasons why you may need knee replacement include Osteoarthritis, Rheumatoid arthritis, Traumatic arthritis, Osteonecrosis, and other inflammatory diseases that affect the knee joint.

Infected Knee Replacement

Postoperative knee infection is one of the complications of orthopedic surgery. A small number (about 1%) of people with TKR may have joint infections. Infection can occur immediately after surgery (even while in the hospital) or weeks or months later.

Bacteria can invade through the wound and colonize the implant. Because implants are non-organic, there is no blood supply and thus infections are difficult to eradicate.

What makes it more likely to develop an infection after my knee replacement

Malnutrition
Diabetes mellitus
Use of steroids
Obesity
Excess use of alcohol
Smoking
Peripheral Vascular Disease
HIV and other immunity-affecting diseases
Lymphoma

Types of Infection to Knee Replacement

1. Early Infection

2. Late infection

Early infections occur within days and weeks post-surgical procedures while Late infections occur after months and are difficult to salvage compared to the early infections.

Signs and Symptoms of Infected Knee Replacement

Pain
Fever
Weakness
Redness
Stiffness
Chills
Drainage from the wound site

See your doctor right away if you experience any of these symptoms. Prompt action in the event of an infection can save joints and sometimes even legs.

Ways to prevent infection

Screening of the infection before surgery

Identifying who is at risk and trying to mitigate the cause

Quit smoking, control of blood sugar, healthy weight

Preparing the patient for surgery using infection control measures (CDC guidelines)

Using strict sterile techniques and instruments

Special ( Ultraclean) operating room design with laminar airflow

Short operating time and adherence to the operating room protocols

Clean ward (cohorting, prevention of contact) and a sterile dressing

Use of Antibiotic before and after surgery

What Next After an Infected Knee Replacement?

An infected knee replacement is not the end of the road as it can be salvaged regardless of either early or late infection. The treatment for an infected total or partial knee replacement depends on the type of infection and its severity.

1. Antibiotics

Antibiotics are best used in the management of superficial infections (infections affecting the skin and surrounding soft tissues) and early infections. Doctors usually employ the use of oral antibiotics as well as intravenous antibiotics.

2. Surgery

Surgical options are employed when a knee replacement infection is late or deep (infection affecting the replaced knee). These surgical procedures include:

A. Debridement: Debridement also known as surgical wash out is used when the deep infection occurs early and, in such cases, all knee prostheses will not be removed. The surgeon removes the infected tissues around the implant and cleans up the implant or changes only the plastic insert. Thereafter, the patient will be placed on intravenous antibiotics for a long period.

B. Staged Surgery ( Revision knee replacement):

This involves surgical procedures to remove the artificial implants and replace them. This is usually done for deep and late infections that go beyond the skin and soft tissues. The procedure involves the removal of the implants, debridement or surgical washout, placement of a spacer soaked in antibiotics to help in maintaining the joint space, intravenous antibiotics use, and new joint replacement surgery.

Further, read:

1. Overview | Joint replacement (primary): hip, knee, and shoulder | Guidance | NICE

2. Guidelines Library | Infection Control | CDC