Since the 1970s, some doctors have treated arthritic knees by injecting them with hyaluronic acid, a substance originally derived from the combs of roosters. Specialists have zealously promoted this therapy, costing patients a few hundred dollars a pop and repeated so widely that Medicare alone pays $300 million annually for it. Doctors argue it reduces pain and increases joint mobility.
It hardly lives up to this billing, though, offering patients scant more relief than a placebo (saline, or salt water), researchers found after scrutinizing a half century’s worth of data from 169 clinical trials involving more than 20,000 patients.
The highly popular viscosupplementation procedure, as reported by Stat, a medical and scientific news site, showed an average effect “about 2 points beyond placebo effect on a pain scale that runs from 1 to 100.” The researchers from Canada, Britain, and China concluded this from their study, as published in BMJ, a respected medical journal of the British Medical Association:
“Strong conclusive evidence indicates that, among patients with knee osteoarthritis, viscosupplementation is associated with a clinically irrelevant reduction in pain intensity and with an increased risk of serious adverse events compared with placebo. Our findings do not support the broad use of viscosupplementation for the treatment of knee osteoarthritis.”
Stat reported that the researchers said doctors should not ignore the risks posed by this therapy (as shown above):
“Some studies [they examined] reported gastrointestinal inflammation and infections, cardiovascular problems, blurred vision, and dizziness, among other issues, in patients receiving hyaluronic acid, though the authors dismissed those as unrelated to the injections. In 2018, more than a quarter of Medicare expenditures for viscosupplementation were incurred for treating subsequent joint infections, the paper says. Since people who participate in trials tend to be healthier than the general population, those risks could be even more pronounced in real-life settings.”
To be sure, as the Stat article reports, patients are seeking relief from pain and discomfort when they consider injections, which they hope will be preferrable to surgery:
“Osteoarthritis is an incurable, chronic condition that occurs as cartilage breaks down in the knees, hips, hands, or other joints, resulting in pain, limited range of motion, and swelling. More than 32 million adults in the United States have osteoarthritis, according to estimates from the Centers for Disease Control and Prevention. Since there is no cure, people with osteoarthritis often manage their condition with exercise, physical therapy, medications, and injected therapies …Chronic illness can be a voyage of desperation … When faced with gradually worsening osteoarthritis, patients and physicians alike often go searching for tools that might help avoid surgery. Along the way, many encounter by word-of-mouth, seemingly legitimate health websites, or heavy marketing, a slew of supplements and therapies backed by little-to-no unbiased scientific evidence.”
The researchers, whose experiences in dealing with patients who had undergone this therapy had made them skeptical of it, raised issues about the willingness of doctors to inject patients with a substance with so little evidence for its benefits for so long. Indeed, they noted that shortly after doctors started injecting patients, researchers launched a bevy of clinical trials — so many that their results “far outpaced the field’s capacity to find, appraise, and distil the evidence.”
Companies that provided the injections, in the next phase, conducted their own trials. The researchers said these trials appeared to be started with sufficient rigor — except their results, as too often occur, were not “fully published,” though they “reported similar or worse treatment effects [from injections] on osteoarthritis pain than [the] placebo.”
Further trials then ensured, still at robust levels, and the researchers expressed objections to this, writing:
“[B]etween 2009 and 2021 alone, more than 12 000 patients were subjected to intra-articular injections in viscosupplementation trials, which raises ethical concerns. Based on our trial sequential analysis, a sufficient number of patients have been accrued to confidently conclude that viscosupplementation is not only ineffective compared with placebo but might also be seriously harmful and therefore should be used cautiously in any ongoing trial.”
In my practice, I see not only the harms that patients suffer while seeking medical services, but also their struggles to access and afford safe, effective, and excellent medical care. This has become an ordeal due to the soaring cost, complexity, and uncertainty of treatments and prescription medications, too many of which turn out to be dangerous drugs.
Before they undergo progressively more costly, complex, and risky interventions for knee and joint issues, patients should discuss with their doctors the benefits they may experience from rest, exercise, physical therapy, and drugs. All medical procedures carry risks, and this includes injections, and it is worth noting, as Stat reported, that the American Academy of Orthopedic Surgeons issued clinical guidelines in 2013 and doubled down in 2016, advising against the use of hyaluronic acid injections for patients with knee osteoarthritis.
As for the “next step,” more invasive surgeries — even operations like knee, shoulder, and hip replacements that doctors and hospitals insist have become almost routine — should never be undertaken without extensive discussion, preparation, investigation, and care.
Too many patients have found that knee surgeries, for example, have their “risks and limitations,” and “doctors are increasingly concerned that the procedure is overused and that its benefits have been oversold,” the independent Kaiser Health News (KHN) service reported not that long ago.
Patients, correctly, consider personal mobility a fundamental part of the quality of their lives, and this capacity — along with freedom from discomfort and pain — may argue for the growing business of bone and joint procedures. But we have much work to do to ensure that rigorous evidence exists for treatments before they become widespread, expensive, and of little or no benefit to patients.