The comparison of blood from wound drainage after total knee arthroplasty between postoperative cast immobilization and non splint A. randomized controlled trial

Objectives :This study compared the blood from wound drainage in milliliter after total knee arthoplasty between postoperative cast immobilization and non splint Design:A randomized controlled trial Setting :King Chulalongkorn Memorial Hospital, Bangkok Participants :142 patients, inpatient who had knee osteoarthritis that required total knee arthroplasty Methodology : A consecutive series of 142 knees in 142 patients were divided in cast group and non-cast group by sealed envelopes. The volume of blood from wound drained in both groups were statistically compared by unpaired t-test Results :There were 69 knees in cast group and 73 knees in non-cast group, There was no difference in age, sex , body mass index between both groups. The mean (SD) of blood loss in cast group was 324.7 (129.31 ml) and non-cast groups was 546.8 (122.2) ml The mean difference in blood lost between cast and non-cast groups was 222.14 ml (95% C1:-263.8-180.39). Using unpaired t-test, there was a significant difference of wound drained between cast group and non-cast group ( P< .05). Conclusion :The immobilized knee with cast after total knee arthroplasty can cause blood loss from drained wound less than patient who do not use. Therefore, we recommend to use cast after total knee arthroplasty in patient with rare blood group.