We stumbled upon three recent studies of knee osteoarthritis (OA) that shed interesting new light on a condition that all orthopaedists deal with.
–A “network” meta-analysis in the Annals of Internal Medicine looked at 137 randomized trials of OA treatments comprising more than 33,000 participants. Treatments analyzed included acetaminophen, diclofenac, ibuprofen, naproxen, celecoxib, intra-articular (IA) steroids, IA hyaluronic acid, oral placebo, and IA placebo. For pain, all active treatments except acetaminophen yielded clinically significant improvement. IA hyaluronic acid came out on top for pain relief, although the authors postulated that an “integrated” placebo effect may explain that finding.
–A cost-modeling study in Arthritis Care & Research, co-authored by JBJS Deputy Editors for Methodology and Biostatistics Jeffrey Katz, MD and Elena Losina, PhD, revealed that the per-patient cost attributable to symptomatic knee OA over 28 years is $12,400. Any expanded indications for total knee arthroplasty (TKA) and a trend toward increased willingness among patients to undergo knee surgery will increase that cost. The researchers found that patients tried nonsurgical regimens for a mean of 13.3 years before opting for TKA, and they stress the need for more effective nonoperative therapies for knee OA.
–Wine drinkers, rejoice! A retrospective case-control study in Arthritis Research & Therapy found that people who drank four to six glasses of wine per week were less likely to develop knee OA than nondrinkers. Meanwhile, beer drinkers may want to switch to wine. The same study found that people who drank 8 to 19 half-pints of suds per week had an increased risk of developing knee OA. Researchers found no link between total alcohol consumption and risk of knee OA. The authors postulate that the resveratrol found in wine may be chondroprotective, and that the linkage between beer and increased blood levels of uric acid may explain the opposite finding. It’s wise to remember that studies investigating one or two dietary items can be less-than-definitive because they are usually retrospective, subject to recall bias, and do not account for complex interactions among many nutrients.
Two recent studies revealed that valgus bracing may be more effective than acupuncture for treating knee osteoarthritis.
A JAMA study of nearly 300 people 50 and older with chronic knee pain and morning stiffness found that 12 weeks of acupuncture, delivered via both needles and laser, provided no substantial pain or function benefits at 12 weeks or one year, relative to no acupuncture or a sham laser procedure. One interesting aspect of this study was its so-called Zelen design; participants were consented after randomization, and those randomized to receive no acupuncture were unaware that they were in an acupuncture trial. According to the authors, “Zelen designs can reduce the risk of bias in a treatment trial in which knowledge of the intervention may influence recruitment…and outcomes.”
Conversely, a meta-analysis of six randomized studies totaling more than 400 patients in Arthritis Care and Research found that a valgus knee brace can improve pain and function in people with medial knee osteoarthritis. The analysis examined trials that compared valgus bracing with no orthosis and with other types of orthoses, such as neoprene sleeves. In the former comparison, the valgus brace yielded improvements in both pain and function; in the latter comparison, valgus bracing improved pain but not function. An editorialist commenting on the findings opined that the clinical goal going forward should be to identify those patients who are most likely to benefit from this type of bracing and who will comply with instructions for use.