Acupuncture for OsteoarthritisBY GIL BARZILAY, PhD, Dipl CM
EVIDENCE SUMMARY: OSTEOARTHRITIS
Strength of evidence
ACUPUNCTURE FOR OSTEOARTHRITIS
Osteoarthritis is a chronic disease characterised by the deterioration of cartilage in joints that results in bones rubbing together, creating stiffness, pain, and impaired movement. Although osteoarthritis may affect any joint, the knee, hip, and hand are most commonly affected.1 Knee osteoarthritis accounts for more than 80% of the disease’s total burden and affects at least 19% of American adults aged 45 years and older.2
Osteoarthritis (OA) is a major contributor to functional and social impairment, physical disability and poorer quality of life in older adults and increases the risk of further health issues. While OA is related to ageing, it is also associated with a variety of risk factors, including obesity, lack of exercise, genetic predisposition, poor bone density, occupational injury, trauma, and gender, with a predominance in females compared to males. The prevalence of OA is increasing due to a rise in contributing factors such as obesity and an ageing population.1
CLINICAL EVIDENCE FOR PAIN RELIEF & IMPROVED JOINT FUNCTION
The effects of manual acupuncture in reducing pain and improving physical functioning can further be enhanced using electroacupuncture, as shown by Chen et al.6 in their meta-analysis reporting that electroacupuncture was superior to manual acupuncture with a 12% greater chance of reducing pain and improving physical functioning.
HOW ACUPUNCTURE TREATS OSTEOARTHRITIS – BIOLOGICAL MECHANISMS
Typical options in the treatment of OA include pain medications, hyaluronate injections to lubricate the joint, corticosteroid injections and joint replacement surgery while protective measures include exercise and dietary advice. Some of these interventions are risky with a poor benefit to harm profile, especially for the elderly, and many people are reluctant to have them.11
A review by Birch et al.12 in 2017 compared the effect size (ES) of common treatments for knee osteoarthritis, where an effect size of 0.3 or less is considered small; 0.5 is moderate yet clinically meaningful (as defined by the UK NICE) and 0.8 is large.
Commonly prescribed analgesics such as acetaminophen have a small ES (0.14–0.21), whereas stronger analgesics such as non-steroidal anti-inflammatory drugs (NSAIDs) and cyclooxygenase-2 (COX-2) inhibitors have a larger ES (0.29–0.44), but their adverse effects are substantial with ~2000 deaths in the UK alone as a result of using normal doses of NSAIDs 12,13 and up to a 60% increase in the risk of heart attack.14 Topical NSAIDs have shown a moderate effect size (0.40), but their effect usually last for the first 1–2 weeks.12
Opioids have shown the largest treatment effect with effect size of 0.78, but are not recommended due to their serious adverse effects and addiction. Since first approved by the FDA in 1996, it is estimated that 650,000 Americans have died due to opioid overdose, with more than half of those deaths occurring since 2016.15
Acupuncture had a small effect size (0.16–0.35) when compared with sham acupuncture needling, which is in line with current understanding that sham acupuncture is not physiologically inert and has some level of beneficial effect, artificially reducing the magnitude of the ES in comparison with sham.16 However, when acupuncture was compared to standard therapy, including painkillers, it was second only to opioids with a meaningful moderate effect size of 0.57, and with a favourable safety profile and minimal side effects.17
Acupuncture has also been shown to be cost-effective for the management of pain such as lower back pain, headaches and OA.18 A study by Woods et al. 19 published in 2017 compared the cost and benefits of acupuncture, supports such as braces or insoles, manual therapy, electrotherapy (laser/ light therapy, electrical and magnetic stimulation, transcutaneous electrical nerve stimulation), heat treatment, and usual care. Only transcutaneous electrical nerve stimulation (TENS) and acupuncture were considered cost-effective.