Radiofrequencies for painful total knee Arthroplasty: rationale and applications. A review

Abstract

Total knee arthroplasty ensures patients a safe recover of function and pain relief. It is performed on millions of patients worldwide. Nevertheless, in a certain percentage of case there is an unexplainable persistence of pain in presence of a well-performed surgery. This is called mystery knee or persistent postsurgical pain (PPSP) and the surgical treatment is difficult since the factors to correct are unknown. Radiofrequencies are used for the treatment of chronic nervous pain and also in some cases of osteoarthritis. They function with well-demonstrated and safe physical and microbiological processes. Therefore, the idea to apply radiofrequencies on one or several nervous braches of the knee (superolateral, superomedia, middle, inferolateral (recurrent), inferomedial and lateral retinacular) is quite interesting and can provide pain relief for this particular group of patients. The procedure is safe and not permanent and can be repeated if necessary. There are not many studies on this topic, but the first results report good outcomes. Costs may be an issue, but once the patient has no pain, the rehabilitation is more effective and the surgery con is postponed or deleted. This review discusses the basis of PPSP after knee surgery, the biological mechanism of action of the radiofrequencies and the clinical application after total knee arthroplasty.