According to the World Health Organization, osteoarthritis affects approximately 528 million people globally, with the knee being the most commonly affected joint. Over 10 per cent of knee osteoarthritis patients are treated with injectable corticosteroids or hyaluronic acid. Two recent studies have tried to address this question.
The first study, published in Radiology, compared the effectiveness of these two common knee injections. US researchers analysed data from 210 participants, with an average age of 64; 60 per cent were women. Among them, 70 individuals received a single injection—either corticosteroid or hyaluronic acid—while 140 matched controls received no injections.
All participants underwent knee MRI scans two years before their injection, at the time of injection and again two years afterwards. Corticosteroid injections were associated with faster progression of knee osteoarthritis and greater knee joint damage, particularly to the cartilage, compared with both the hyaluronic acid group and the control group. In contrast, hyaluronic acid injections appeared to slow the progression of osteoarthritis and resulted in less joint deterioration.
While both treatments offered pain relief, only hyaluronic acid did so without contributing to further joint damage. “Our study directly challenges a common clinical practice: the use of corticosteroid injections for knee osteoarthritis symptom relief,” said the study. “It presents robust evidence that corticosteroids accelerate structural knee degeneration, even after a single injection.”
A second study, published in PLOS One, compared the effectiveness of 12 non-drug treatments for knee osteoarthritis by analysing data from 139 clinical trials involving 9,644 patients. The interventions included low-level laser therapy, high-intensity laser therapy, electrical nerve stimulation, ultrasound therapy, wedged shoe insoles, knee braces, exercise programmes, water-based therapy, kinesio taping and shockwave therapy.
Among these, knee braces performed best in reducing pain, improving function and relieving stiffness. Hydrotherapy (water-based exercise) and structured exercise programmes such as aerobic or mind-body exercises were also found to be effective in reducing pain and improving mobility. In contrast, ultrasound therapy consistently ranked lowest in effectiveness for treating knee pain.
Researchers concluded that knee braces may be the most recommended non-drug therapy for managing knee osteoarthritis, followed by hydrotherapy and exercise.