Level 2: Mid-level evidence
Meniscal tears are common in patients with osteoarthritis of the knee, and symptomatic tears are frequently treated with arthroscopic surgery. Existing data from randomized trials show arthroscopic debridement is not effective for treating knee osteoarthritis,1,2 but these trials have not specifically addressed meniscal tears. A new trial compared initial physical therapy vs. initial arthroscopic surgery for symptomatic meniscal tears in this population.3
A total of 351 patients with mild-to-moderate osteoarthritis and symptomatic meniscal tear were randomized to one of two treatments and followed for one year. The first group began treatment with a standardized physical therapy regimen but had the option for surgery at the discretion of patient and surgeon.
The second group had immediate arthroscopic partial meniscectomy followed by the same standardized physical therapy. The physical therapy regimen for both groups included interventions to address inflammation, range of motion, muscle strength, aerobic conditioning, functional mobility and balance. There were one or two weekly sessions plus home exercises for approximately six weeks, depending on patient progress.
All patients could have acetaminophen or NSAIDs as needed, and intra-articular glucocorticoid injections were permitted. The primary outcome was change in physical function as measured by the Western Ontario and McMaster Universities Osteoarthritis Index scale (WOMAC score, 0-100 scale with higher scores indicating more severe symptoms). The mean WOMAC scores at baseline were 37.5 in the physical therapy group and 37.1 in the surgery group. A change in WOMAC score of eight points was considered clinically meaningful.
Patients who did not complete follow-up (6% at six months and 9% at one year) were excluded from the analyses. Both groups showed significant improvement in physical function by WOMAC score at six months (decrease in score 18.5 vs. 20.9) and one year (decrease in score 22.8 vs. 23.5).
There were no significant differences in improvement between groups at either time point. Nearly one-third of the physical therapy group crossed over to surgical treatment in the first six months. In the physical therapy group, 44% had clinically relevant improvement at six months without crossing over, compared with 67% in the surgery group (P <0.001). There were no significant differences in adverse events or pain at six or 12 months.
Most of the patients in the physical therapy group who had surgery in the first six months had little functional improvement prior to crossover. However, their one-year outcomes were similar to those seen in the immediate-surgery group, suggesting that delaying surgery did not have a detrimental effect.
It should be noted that the WOMAC questionnaire is a valid measure of physical function during basic activities of daily living, but it does not assess high-level function as may be required for work or sports. Nevertheless, these results suggest that physical therapy may be an appropriate first option for many patients with osteoarthritis and meniscal tears and that it may be possible to reserve surgery for those who do not benefit from physical therapy alone.
Alan Ehrlich, MD, is a deputy editor for DynaMed, in Ipswich, Mass., and assistant clinical professor in Family Medicine, University of Massachusetts Medical School in Worcester.
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