Treatment for Osteoarthritis of the knee (OA knee) can remain as basic as physical and medical therapy alone, or can cross into the more serious surgical sector with arthroscopy, a minimally invasive procedure in which cartilage fragments and calcium crystals are removed from the knee joint. Though arthroscopic surgery has long been a popular means of treating OA knee, particular evidence on its benefits over exclusive therapy is lacking. A randomized, controlled trial was conducted to distinguish between the effectiveness of just physical and medical therapy versus arthroscopy and therapy.
In order for patients to participate in the study, they had to be 18 years or older with idiopathic (arising spontaneously or from an unknown or obscure cause) or secondary OA knee with a grade of 2, 3 or 4 radiographic severity (as rated by the Kellgren-Lawrence classification scale.) Exclusion criteria included patients with large meniscal tears, inflammatory or post-infectious arthritis, previous knee trauma, serious medical illness and pregnancy. After conducing the number of participating patients according to the criteria, they were each sent to seven orthopedic surgeons to be assessed for eligibility. Surgeons performed a detailed examination of the knee and documented the range of motion, presence of effusion and the results of meniscal and stability tests.
A group of 277 patients was assessed for eligibility, which was reduced to 188 after those deemed ineligible were dismissed and 31 others withdrew. Once patient eligibility was determined, the 188 were split into two groups of 94 and randomly assigned to either the control group, which received only optimal physical and medical therapy, and the surgery group, which received arthroscopic surgery and optimalphysical and medical therapy. Surgery was performed within six weeks of group assignments. The physical and medical therapy programs, which were identical for both groups, began seven days after surgery and consisted of a one-hour session, once a week, for 12 consecutive weeks. Participants of both groups were also given information on a home exercise program and instructed on how to go about daily tasks such as walking, using stairs and dealing with cold and heat. An unsupervised exercise program was assigned at home after the 12 weeks of therapy until its conclusion at 2 years. Both groups also reviewed personalized medical treatment plans with an orthopedic surgeon, which additionally recommended the use of acetaminophen, non-steroidal anti-inflammatory drugs, glucosamine and intra-articular injections of hyaluronic acid. Patients were seen at a clinic for evaluation 3, 6, 12, 18 and 24 months after the initiation of treatment, where a nurse unaware of the study scored them on a number of questionnaires regarding their progress.
Improvement scores were based on the WOMAC, a measurement system for both knee and hip OA. Overall, at the end of the 2-year trial, patients assigned to arthroscopic surgery did not show any greater improvement in WOMAC scores than those who received therapy exclusively. At 3 months, there was a slight improvement in the surgery group compared to the control group, but the differences between the two did not appear at any future dates. This is purportedly attributed to a short-term placebo effect of the surgery. Secondary measures, which assessed physical function, pain and health-related quality of life also did not present any significant difference between the control and surgery groups. A small number of limitations may have further contributed to the results reached in the trial, such as the fact that only 68% of participants evaluated were deemed eligible for the study, but all inclusion and exclusion criteria were designed to create an ideal setting for comparing the two groups. Therefore, going by this study, there is no additional benefit of arthroscopic surgery over optimal physical and medical therapy.
-As reported in the Sept. ’08 edition of The New England Journal of Medicine