The best treatment for infection associated with a total joint is prevention. For this reason, every effort is made to prevent a total joint from getting infected. If infection occurs, the only way to treat it is with surgery. Antibiotics alone will not cure an infection.
If the infection is acute, that is, it occurs in the first several weeks after surgery and the bacteria that is infecting the prosthetic joint is sensitive to antibiotics, then we typically re-open the hip, thoroughly and meticulously debride and irrigate the area while removing and then replacing the modular ball and plastic liner. The patient is treated with IV antibiotics during and then after surgery (typically for 6 weeks) and then take antibiotics by mouth (PO). This may salvage the artificial joint and clear up the infection. It may also fail.
If the infection is chronic , that is, has been present for more than several weeks or the infection is caused by several organisms (bacteria), a fungus, or an organism that is particularly resistant to common or easily administered antibiotics, then patients typically must undergo a two stage re-operation to treat and hopefully cure the infection. The first re-operation involves removing the total hip prosthesis, extensively and meticulously debriding the infected area and irrigating the area. The next step is to implant a temporary total hip (much like a temporary dental implant prior to the definitive one) to function as a “dynamic spacer.” The temporary THR is provisionally anchored to the bone using bone cement. Large quantities of antibiotics are added to the bone cement which leach out into the local tissue to treat the infection. IV antibiotics are also given (typically for 6 weeks) followed by PO antibiotics.
We perform the second operation after the antibiotic courses are complete and further studies indicate that the infection has been cured. In the second-stage surgery, we remove the temporary total hip, again irrigate and debride the joint and implant the definitive revision components. We continue antibiotics until intraoperative cultures are negative and many times longer.
Sometimes it is not possible to place a temporary total hip (“dynamic spacer”). In this case, antibiotic impregnated bone cement are formed into beads to maximizes exposed surface area and placed on a wire and then implanted (“static spacer”) until a definitive THR can be reimplanted after the infection is fully treated.
While the two-stage operation is optimal for addressing chronic infection, it is not always practical or appropriate. Some patients, for example, are too frail or sick to undergo two major surgeries. For patients who have already undergone one or more revision surgeries (in which the incidence of infection is much higher than in primary THR), removing the prosthesis could preclude or compromise the ability to re-implant another. In these cases, the joint is surgically debrided and irrigated, the modular head and liner are replaced with new ones, the patient is treated with IV antibiotics and then remains on a suppressive PO antibiotic most likely for life. Our goal in these cases is not to eradicate the infection but rather to suppress the infection so it is not expressed.