ARTHROSCOPIC PARTIAL MENISCECTOMY IN INDIVIDUALS WITH SYMPTOMATIC OSTEOARTHRITIS: WHO BENEFITS?

Purpose: Meniscal tears and osteoarthritis (OA) frequently coexist; there are limited data to guide the use of arthroscopic partial meniscectomy (APM) among those with both problems. Our objective was to evaluate the capability of readily available information to predict APM outcomes.

Methods: In a hypothetical population of individuals with knee pain, meniscal tear and OA, we examined the ability of four clinical findings to distinguish the primary source of pain (i.e., due to tear versus OA). The four clinical findings were tear type, presence of mechanical symptoms, pain pattern, and bone marrow edema. In the base scenario, we assumed 50% of individuals had pain primarily due to meniscal tear. We computed likelihood ratios for each of 36 possible combinations (i.e., the ratio of probabilities that a given combination occurs in tear-related -- as opposed to OA-related -- pain). We ranked these 36 combinations from most to least likely to represent pain due to a tear.  Combining Bayesian theory and decision analysis, we evaluated disease-specific health related quality of life and costs of patients managed with and without APM.

Results: Figure 1 displays the distribution of individuals with tear- vs. OA-related pain. Rank 1 represents individuals with the highest likelihood of tear-related pain; rank 36, those with the highest likelihood of OA-related pain. The ranking effectively separates individuals who likely have tear- vs. OA-related pain: 78% of individuals with tear-related pain are in ranks 1-16; 81% of those with OA-related pain are in ranks 24-36. The indeterminate middle ranks, where individuals are as likely to have tear- as OA-related pain, include <8% of the total population. In the base analysis, the greatest increase in ten-year disease-specific health related quality of life is achieved at APM threshold rank 19 and lowest ten-year total costs at rank 14. These findings are robust across broad ranges of assumptions, including eliminating tear type and pain pattern from the predictive model.

Conclusions: Our analysis indicates that a substantial proportion of individuals with meniscal tear and OA are unlikely to benefit from APM. Despite the lack of randomized clinical trial data to guide decision making in patients with concomitant meniscal tears and OA, easily obtainable clinical information can differentiate those who are likely to benefit from APM from those who are not.