This study is a single-center, double-blind, 15-week, 3-period crossover clinical trial. Subjects will complete each of the following 5-week long periods (unless they withdraw from the trial): 1) placebo pills and topical lidocaine patches, 2)extended-release oxycodone pills and placebo(vehicle) patches, and 3)placebo pills and placebo patches. Sixty subjects will be randomized to one of 6 treatment sequences. It is expected that this trial will take approximately 2 years to complete.