This study was conducted to evaluated the effects adding continuous passive motion(CPM) each day to the entire postoperative program of patients who received a total knee replacement(TKR). A retrospective chart review was completed for 31 patients(12 with bilateral involvement, totaling 44 knees)who received a TKR between 1996 and 1998. The data analysis compared the following variables for 28 patients who received CPM and 16 patients who received no CPM: the length of hospital stay(LOS), the frequency of postoperative complications, the number of post-operative days(PODs) range of motion (ROM). The CPM Group showed significant decreases in the frequency of complication(p<0.05), the LOS(p < 0.05), and No difference was demonstrated in the ROM of the two groups. We concluded that CPM was an effective adjunct to physical therapy care of patients undergoing total knee replacement.