Infection Prevention
updated 10/8/2023 tpg
Infection in joint replacement is a major problem. The infection rate varies widely among surgeons, hospitals and types of major surgeries. The national deep infection rate for joint replacement is 1-2%. Numerous factors affect this rate. Revision surgeries carry a higher rate of infection. Transfusion increases the infection rate. Patient factors such as obesity, diabetes, smoking and various immune suppression conditions or medications increase the rate of infection. Long hospital stays and rehab facility stays increase risk.
The factors influencing the rate of infection are really too numerous to elaborate on here. You can check databases to get estimates of infection rates at various hospitals, but you cannot discover the infection rate of individual surgeons. Medicare keeps data on the 3-month infection rate for hspitals. Generally smaller hospitals with less severely ill patients and outpatient surgery centers have fewer resistant bacteria floating around.
If common minor wound problems are not managed correctly deep infection can result. In the past, most surgeons believed that deep infections around implants could only be cured by removing the implant and later reimplanting another implant after the infection was cured. I have been curing many of these for years successfully without implant removal. Now there is mounting evidence from many sources that this can be successful in a high percentage of cases. If aggressive treatment fails, or if a chronic well-established infection is present, implants still need to be removed.
It is very difficult to study infection because the diagnosis and time of onset is not always clear. Therefore we arbitrarily declare that any deep infection diagnosed before 3 months is an acute perioperative infection. It is thought to be directly related to the operation, but we never know for sure. Bacteria can fall into the wound (there is actually no such thing as a truly "sterile" operation) or they can crawl into the wound that has not yet sealed postoperatively. Also, I would consider any infection that is diagnosed after 3 months in a patient who has had ongoing minor wound problems prior to 3 months as an acute perioperative type. However, these are not typically captured in the data reported to medicare. Medicare rates are therefore falsely low. Therefore when this is studied, we also sometimes consider any infection diagnosed by 1 year postoperative as acute perioperative. But these would be falsely high because some later infections after the wound has sealed uneventfully could have spread through the bloodstream from another site in the body.
The benchmark mean 3-month infection rate for hospitals is approximately 1%. There is no official surgeon specific data. The estimated (not oficially reported to medicare) 1-year infection rate in independent studies is 2.5%. My personal 3-month infection rate in the last 10 years is 0. My 1 year rate is 0.06% (Patienteducation/latest data). These fare far below the benchmarks listed. I would argue that an individual surgeons infection rate is much more important to know than the rate in a given hospital. But most surgeons don’t even keep such data, much less publish it. In addition, the few infections that I do see are usually cured without loss of implant (Patient education/ scientific publications). Perioperative infection is a serious complication that is under the surgeons control. I have managed to drive this problem far below the reported benchmark reates, but not to zero.
There is also another category of infection that lies completely out of the control of the surgeon. These are late hematogenous infection (after 1 year). Infection can travel from distant sites to the artificial joint and set up shop. Fortunately these are very rare, I would estimate far less than a 1% lifetime risk. But good data is missing. Less frequently these can be cured without implant removal if the patient is diagnosed in a timely fashion and has not developed a chronic established infection. It is still a challenge.
In my opinion, deep infection of an implant is the single worst complication that a patient can suffer after joint replacement. Fortunately, in my hands, this problem has been nearly eliminated. But the rare cases where this still happens are still an immense challenge to treat.