Antibiotic Prophylaxis for Total Joint Replacements

ABSTRACT & COMMENTARY

Synopsis: Antibiotic prophylaxis for dental work is indicated for many patients who have had total joint replacements, although its value remains uncertain.

Source: Fitzgerald RH, et al. Advisory report: 20 antibiotic prophylaxis for dental patients with total joint replacements. JADA 1997;128:1004-1008.

The american dental association and the american Academy of Orthopedic Surgeons, plus an infectious diseases specialist have come up with some reasonable recommendations for antibiotic prophylaxis for dental work in patients who have total joint replacements (TJR).

The situation is a difficult one because of the complexity of the variables to consider and the lack of information about the rare event of a TJR infection due to dental work. The recommendations are not simple, but they do delineate some significant risks. The first consideration is to identify patients who appear to be at increased risk for hematogenous joint infections. Risk factors include the inflammatory arthropathies, immunosuppression, insulin-dependent diabetes, malnourishment, hemophilia, joint replacement within the last two years, and a history of a prior TJR infection. There appears to be no increased risk of infection for patients with pins, plates, or screws.

The article also reviews the incidence of bacteremia from dental procedures, which is highest with dental extractions, periodontal procedures, implant placement, root canal instrumentation, placement of orthodontic bands, intraligamental local anesthetic injections, and prophylactic cleaning of teeth or implants when bleeding is anticipated. A low incidence of bacteremia is associated with restorative dentistry, routine local anesthetic injections, intracanal endodontic treatment, placing a bridge or a rubber dam, suture removal, removal of orthodontic appliances, taking oral impressions, fluoride treatments, and orthodontic appliance adjustments.

The panel did make clear recommendations on selection and dosing of antibiotics for prophylaxis—one dose of 2 g of amoxicillin one hour before the procedure. Cephalexin and cephradine are considered reasonable alternatives—again at a dose of 2 g prior to surgery. These drugs can be given in comparable amounts parenterally if need be. Only a single dose of antibiotic is considered effective. If patients are allergic to penicillin, clindamycin 600 mg by mouth or intravenously is suggested one hour before surgery.

COMMENT BY ALAN D. TICE, MD

It’s nice to see associations getting together on a thorny issue—especially in these times of increasing antibiotic resistance and excessive use. The panel points out that there is a greater likelihood of bacteremia from common daily events (including toothbrushing, mastication, defecation, etc.) than there is from usual dental procedures.

There is, nevertheless, concern about the nearly half a million patients who receive total joint arthroplasties each year in the United States. Some are bound to get infected, and hence there is a risk not only to the patient but to the doctor or dentist responsible for preventing the infections as well. There are some who have been overzealous in their recommendations for antibiotic prophylaxis for joint replacement—with few data to base this on. The risks of adverse effects from unnecessary antibiotics are significant.

Antibiotic prophylaxis is a typical dilemma with which physicians and dentists are faced. They may be aware that the chances of joint infection arising from dental work may be extremely low, but, if it occurs without antibiotic prophylaxis, the risk of a malpractice suit is high. The likelihood of an adverse effect from an antibiotic is about 5% but can be easily justified in court. Decisions in antibiotic prophylaxis may be made more with the attorney in mind than the patient. This advisory statement is quite helpful from a legal standpoint and should be useful in discouraging antibiotic prophylaxis unless clearly indicated. The article also mentions the potential conflict between the patient’s usual physician and their dentist—which can hopefully be resolved with easy communication.

The bottom line is that antibiotic prophylaxis for dental work in orthopedic patients is indicated only for those who have had total joint replacements and that, even then, the need is not clear without risk factors or a high likelihood of bacteremia. The antibiotic of choice is a single dose of amoxicillin, with clindamycin as an alternative.