Most people know bacteria like streptococcus (“strep”) and staphylococcus (“staph”) can cause all kinds of infections — strep throat, inflamed nailbeds, skin infections, and so on. These same agents can also cause joint infections referred to as septic arthritis. Any puncture, wound, bite, surgical procedure, or body infection (e.g., urinary tract or upper respiratory) can result in an infectious joint. The bacteria move along through the blood system to the joint.
Recognizing and diagnosing septic joint arthritis isn’t always easy. The patient may not have a known history, trauma, or other event they can link with the new symptoms of joint pain, redness, and swelling. It’s not until the physician draws some of the fluid from the joint and sends it to the lab that a diagnosis can be made.
In this article, hand surgeons from Columbia University Medical Center in New York City review the evidence for diagnosing and treating a septic wrist. They try to pinpoint the best way to diagnose this problem but research results are limited. Many surgeons rely on their own clinical expertise for this one. Lab tests (blood work, joint fluid analysis) give some idea of what’s going on but are not accurate enough to be used as the only means of diagnosis.
For example, some bacteria don’t show up in the joint fluid culture at all. In fact, in the case of gonococcal bacteria, the culture is negative 50 per cent of the time when the patient really does have an infectious process going on. Elevated white blood cells and sed rate (erythrocyte sedimentation rate) suggest an inflammatory response but aren’t specific enough to say what for sure.
With aspiration (removal) of joint fluid, lab analysis will eventually be positive — but sometimes, not until significant damage has been done to the joint. The bacteria can spread beyond the joint and cause further systemic problems. It’s far better to find out quickly that there is a bacterial infection and nip it in the bud, so-to-speak.
So, what do the experts recommend? Start with an X-ray of the joint followed by needle aspiration and lab analysis. Put the patient on a broad spectrum intravenous antibiotic. Broad spectrum means that until the specific “bug” (bacteria) is identified, choose an antibiotic that will kill them all (or as many as possible). As soon as the lab culture comes back with the exact bacteria present, switch the patient to an oral antibiotic that will specifically target those bacteria.
Is there any scientific evidence to support these guidelines? Not really. Whether or not this approach is what works best has never really been studied. Likewise, the use of intravenous (IV) versus oral antibiotics for a septic wrist is based on “conventional” wisdom (i.e., it makes sense and that’s the way it’s been done for a long time).
What other treatment or management techniques are used for a septic wrist? The fluid can be aspirated (removed) as many times as needed. In some cases, one time is all that’s required. With the antibiotics, aspiration is followed by pain relief, decreased swelling, and improved joint motion.
Surgery may be needed to irrigate and debride (clean out) the joint. This procedure helps remove bacteria and infection (pus) and give the joint a chance to heal. Just like with the aspiration procedure, surgical drainage may be done more than once.
Surgical drainage is almost always needed when the bacterial infection occurs as a result of a joint replacement. The implant may actually have to be removed, the wrist cleared of infection, and a new implant (or wrist fusion) procedure performed. In all cases, surgery is recommended if the infection has progressed to the point of erupting through the joint or when needle aspiration doesn’t yield the expected results (i.e., the patient doesn’t get better quickly).
The authors conclude what surgeons really need is an evidence-based Clinical Practice Guideline. Such a document would offer guidelines for evaluating, diagnosing, and treating a septic wrist joint. But much more research is going to have to be done before such a set of clinical guidelines can be written.
Studies are needed to compare types and timing of antibiotics, number of aspirations to do before considering surgery, and most effective lab tests for diagnosis. Patients will have to be followed for several years to see what kind of outcomes are possible with different treatment protocols. Of course, the goal is to find the fastest, most effective treatment with the lowest cost and fewest complications or problems.