With few solutions available, treatment of knee osteoarthritis is challenging, but a randomised control trial published in Arthritis and Rheumatology has found that, at least for short-term relief, ultrasound-guided genicular nerve block (GNB) was effective.
The global prevalence of knee osteoarthritis (OA) is ~22.9% of over-40s. Knee OA is a significant cause disability and potentially loss of independence. Treatment remains challenging, with nonsurgical management options such as education, weight loss, exercise therapy, and walking aids. Few recommended pharmacotherapeutic options exist for knee OA, with surgical joint replacement being a definitive treatment strategy for patients with severe disease who are unresponsive to conservative care. For many patients, such as people who are frail or elderly or people with complex comorbidities, surgical intervention may not be suitable.
In a 12-week parallel-group, placebo-controlled randomised trial of GNB, patients in the active arm received 3 injections of 5.7 mg celestone chronodose (1ml) and 0.5% bupivacaine (3ml) to the inferomedial, superomedial, and superolateral genicular nerves. Patients in the placebo arm received saline injections. An experienced radiologist or rheumatologist with the assistance of a senior sonographer used ultrasound to locate the nerves.
At baseline and at weeks 2, 4, 8, and 12, patients recorded their pain and disability on self-report scales. Patients in the active group reported improvements in pain scores at 2, 4, 8, and 12 weeks with a diminution of the effect over time.
These results reflect comparator groups, which also reported an effect reduction at 12 weeks.
“This study demonstrates that genicular nerve block is an effective short-term therapy for pain management in people with knee osteoarthritis,” said corresponding author Ernst M. Shanahan, BMBS, MPH, MHPE, PhD, FAFOEM, FRACP, of Flinders University. “We think it may be a useful treatment option for this group of people, in particular those waiting for, or wishing to defer surgery.”
