A Close Look at Crossovers in Knee RCTs
In a November 16, 2016 JBJS study whose findings have implications for both research and practice, Katz et al. analyzed data from the MeTeOR trial to answer two questions:
- What prompts patients with meniscal tears and knee osteoarthritis who are randomized to physical therapy (PT) in trials comparing PT to arthroscopic partial meniscectomy (APM) to cross over from nonoperative therapy to APM?
- Do those who cross over to APM receive symptom relief that’s comparable to those originally randomized to APM?
After careful multivariate analysis of 48 patients who crossed over in the MeTeOR trial (representing 27% of those originally randomized to PT), the authors identified two factors associated with a higher likelihood of crossover: a baseline WOMAC Pain Score of ≥40 and symptom duration of <1 year. The authors also found that patients who crossed over to APM were just as likely to experience improvement in pain scores as those originally randomized to APM.
From a research standpoint, the authors suggest that future investigators may wish to make “special efforts” to keep patients who present with severe pain and relatively short symptom duration in nonoperative therapy. Clinically, Katz et al. say the findings “underscore the emerging treatment recommendation…to try a PT regimen before opting for APM.”