Effect on deep venous thrombosis with flexion during total knee arthroplasty.

This study investigates the relationship between intraoperative extreme flexion and tibia-femoral dislocation during total knee arthroplasty on the prevalence of postoperative deep venous thrombosis. Knees were randomized into two groups. The control group underwent the procedure according to normal protocol, which kept the knee in extreme flexion and maintained dislocation for the duration of the exposure, whereas the variable group underwent the procedure modified to minimize the total amount of time the knee was hyperflexed and dislocated. Venograms were positive in 42% (39/92) of the control knees and 38% (30/79) of the modified group (p = 0.6). Proximal deep venous thrombosis were found in 12% (11/92) of the control knees and in 16% (13/79) of the modified knees (p = 0.4). No statistical difference could be detected between the two techniques in regards to the incidence of deep venous thrombosis.