 The objectives in this study are to evaluate: 1 efficacy of buprenorphine transdermal system BTDS, ButransTM on postoperative pain following total knee replacement surgery; 2 the impact of BTDS on functional rehabilitative measures after total knee replacement surgery; and 3 the safety of BTDS after total knee replacement surgery. The double-blind treatment period is for 28 days during which time supplemental analgesic medication will be provided to all subjects in addition to study drug. 