Hip joint cooled radiofrequency ablation is an innovative technique that can provide sustained pain relief in patients with chronic hip pain. This technique provides an alternative treatment option to patients who cannot or do not wish to under go surgical treatments including joint replacement surgery. Radiofrequency neurotomy of articular nerves of the hip joint seems to be a safe, effective, and minimally invasive therapeutic procedure for chronic hip osteoarthritis patients who get a positive response to the initial diagnostic block. Radiofrequency neurotomy can also be repeated if necessary in order to provide further relief. This technique may be a useful treatment for chronic severe osteoarthritic pain refractory to other conservative treatments; although further, large-scale studies and longer follow-up periods are needed to not only demonstrate the efficacy but also track any long-term adverse effects. It is also important to note that in some cases injection treatment may not provide the desired results or the pain relief may not be sustained.
At Pain Spa Dr Krishna is very experienced in performing interventional pain procedures.
Although surgery is generally effective for patients with advanced disease, some older individuals with comorbidities may not be appropriate surgical candidates. Furthermore, hip replacement is major surgery and has significant associated risks. Some patients may not wish to consider surgery and prefer non- surgical options. In these patients, radiofrequency (RF) neurotomy of the articular nerves might be a successful alternative to surgery. This procedure is based on the theory that cutting the nerve supply to a painful structure may alleviate pain and restore function.
The sensory nerve supply to the hip joint includes the gluteal, femoral, obturator and sciatic nerves. The innervation of the joint capsule can be divided into the anteromedial, anterolateral, posteromedial and the posterolateral areas that are innervated by the articular branches of the obturator, femoral, sciatic and the superior gluteal nerves, respectively.
Studies have determined that the articular branches of obturator and femoral nerves are major contributors towards pain in the hip joint. Hence these branches become the targets for cooled radiofrequency ablation of the hip joint.
These injections are performed under fluoroscopy guidance. A small amount of local anaesthetic (2ml) is injected around the articular branches of the femoral and the obturator nerves. A response is considered positive if there is at least 50% reduction in pain in the 24hrs following injection.
Patients with a positive response are offered either cooled or conventional radiofrequency neurotomy for a more sustained response. The procedure is usually done on an outpatient basis. The procedure is performed under fluoroscopic guidance to ensure accuracy of needle placement. Patients need to be aware that the outcome of the procedure is variable and they may not receive the desired benefits. Similarly, they must be aware of the transient nature of the therapeutic benefits and that there may need repeated injections.
Radiofrequency treatment is a two-step procedure. The first step is diagnostic, involving injection of local anaesthetic around the articular branches innervating the hip joint, as described above. Patients who experience good pain relief following diagnostic injections are offered radiofrequency denervation treatment. This involves creating a heat lesion around the articular nerves carrying painful impulses from the hip joint. Successful treatment can result in pain relief lasting several months.
Either conventional radiofrequency treatment (70-80°c) or cooled radiofrequency treatment (60°c) can be used. Cooled radiofrequency allows creation of larger-volume, spherical lesions compared to conventional radiofrequency.
Treatment is performed under local anaesthetic and can take 4 to 6 weeks to work.
Complications are rare, particularly if injections are performed using a precise needle-positioning technique. Septic arthritis can be avoided with appropriate aseptic precautions. Severe allergic reactions to local anaesthetics are uncommon. Post-procedural pain flare-up is not uncommon, and may be treated with painkillers. Neurological complications including paraesthesias and numbness have been described but are extremely rare. Radiofrequency treatment can cause patchy numbness of the over lying skin. Incidence of infection is low as the procedure is performed under strict aseptic conditions and the injections are extra articular.