The effect of screws and pegs on the initial fixation stability of an uncemented unicondylar knee replacement

The components were implanted into the medial condyles of 12 preserved human tibiae, and a cyclic load was first applied anteromedially and then posteromedially. The screwed implants failed at significantly higher loads (1634.8±121.6 N, mean±standard error of the mean) than the pegged implants (1103.3±152.0 N). On application of a 19.6-N preload, the screwed implants moved significantly less than the pegged implants