Atrium Health Navicent Infectious Disease

Surgical and Orthopedic Infections

Surgical infections are more common than many people realize. This is why surgical consent forms mention the possibility of postoperative infection.

The Centers for Disease Control and Prevention (CDC) estimate that within 30 days, as many as three out of every 100 surgical patients will develop an infection near the part of their body where their operation took place. In most instances, these infections occur at the site of the surgical wound and respond readily to antibiotics.

When pathogenic bacteria, viruses or fungi affect the site of an orthopedic procedure such as a joint replacement, the results can be devastating, however. For some individuals, successful treatment can require months of hospitalization.

Surgical Site Infections

The most common microorganisms involved in post-surgical infections are the bacteria Staphylococcus, Streptococcus, and Pseudomonas. Infection can take place in a variety of different ways, including airborne transmission, contamination from other parts of the patient's own body and lapses in sterile technique on the part of healthcare providers.

The signs of a surgical site infection are identical to the symptoms associated with any type of wound infection and include redness, induration, localized tenderness and pain, and fever. If the infection is caused by bacteria, the wound may also produce a pus, which is an exudate composed of dead white blood cells and bacteria. Pus from a wound site can be cultured to determine the causative microorganisms.

The CDC recognizes three types of surgical infection:

Superficial

• Superficial infections occur along the line of the surgical incision.

Deep

• With deep surgical infections, the infection occurs in the connective tissues and muscles that underlie the incision. If pus forms, the surgeon may need to lance the wound in order to drain it.

Abscess

• An abscess is a collection of pus that may be caused by bacteria introduced into your body during a surgical procedure but that can occur anywhere in your body, particularly in body organs or the body cavities around organs. The surgeon may need to place a drain to rid your body of this pus.

Risk Factors for Surgical Site Infections

Conditions and behaviors that undermine your body's immune system may increase the likelihood that you will develop a surgical infection. People with diabetes, cancer, HIV, and chronic rheumatoid disorders like lupus and rheumatoid arthritis have a greater risk of infection as do smokers and alcoholics. Additionally, any surgery that lasts longer than two hours has an increased possibility of causing infection.

Preventing Surgical Site Infections

Hospitals, clinics and other locations that provide health care services take surgical infections seriously. Physicians and ancillary health care staff wash their hands thoroughly before delivering any type of patient care. Surgeons and surgical staff wear masks, gowns, gloves, and hair coverings and clean their hands and arms up to the elbow with antiseptic soaps before beginning any kind of surgical procedure. Patients may be dosed with antibiotics both before and after a surgical procedure to decrease the risk of spreading any systemic infection they might be harboring without knowing it.

Orthopedic Infections

Orthopedic infections affect the bones (osteomyelitis) and joints (septic arthritis). Sometimes these infections occur spontaneously, but often they occur as a complication of surgery, particularly joint replacement surgeries.

Every year, approximately 800,000 knee and hip operations are performed in the United States, and that number is likely to increase as the baby boomer population ages. According to research published in "The New England Journal of Medicine" in 2009, approximately two percent of these procedures involve postoperative infection.

Another four percent of these patients will suffer an infection at the site of the prosthetic joint within the 10 years following surgery. Fifteen percent of all hip revisions and 25 percent of all knee revisions are necessitated by infections that affect the prosthetic site. Revision surgery is typically costlier, more complicated, and less successful than the original joint replacement.

Osteomyelitis and septic arthritis symptoms can include tenderness and pain in the area of the affected bone or joint, redness, swelling and other deformities, and changes in the range of motion. If the infection has persisted for a period of time, you may feel chronically fatigued.

Osteomyelitis may require debridement of the bone, which is a complex surgical procedure. A variety of interventions can be used to deliver antibiotics to the site of the infection, and once that is complete, you will likely be put on oral or intravenous antibiotics for at least another six weeks.

Septic arthritis also calls for large doses of antibiotics delivered both topically and systemically. Pus and excess fluid will need to be aspirated from the joint regularly until the antibiotics kick in, and the joint stops producing a discharge.

Bone grafts may be needed to build up bones that can no longer bear weight. In cases where the infection was secondary to a hip or knee replacement, revision surgery may be necessary.

Risk Factors for Orthopedic Infections

Chronic diseases like diabetes that affect blood circulation to bones can increase the likelihood of orthopedic infections as can trauma to the soft tissues around the affected bone or joint. Smoking is a big risk factor because nicotine is a vasoconstrictor, and narrower arteries mean less efficient blood perfusion. Certain prosthetic joint models are also associated with higher rates of infection.

Preventing Orthopedic Infections

If you have had a hip or knee replacement, it is important to seek medical attention if you notice the signs of an infection. Bacteria travel through your bloodstream, and if they colonize the site of your joint replacement, you could develop an infection there that could be very difficult to treat.