Fat emboli in total knee arthroplasty: a prospective randomized study of computer-assisted navigation vs standard surgical technique.

A prospective exploratory study of fat emboli in patients undergoing total knee arthroplasty was performed in patients randomly assigned to surgery with computer-assisted navigation or standard technique. Transesophageal echocardiography of the right atrium was recorded for 5 consecutive 1-minute intervals after tourniquet deflation. Emboli were graded on a scale of 0 to 3 based on embolism size, amount of atrium filled, and duration of embolic shower, creating an overall score of 0 to 9. The mean (SD, range) of the 5 overall scores for each total knee arthroplasty was 6.00 (0.76, 4.6-7.4) for computer-assisted navigation (22 patients) and 6.42 (0.97, 4.6-7.9) for standard technique (22 patients) (P=.14), with a 95% confidence interval for the difference of -0.11 to 0.95. We conclude that any difference in extent of emboli between the 2 surgical techniques is unlikely to be of clinical significance.