A total of 6698 primary knee arthroplasties were included, and a thin bearing was used in 96.5% of these cases. Preoperatively, patients with a thick bearing had significantly lower Knee Society clinical scores (P < .01), a trend toward lower functional scores (P = .06), and more significant coronal plane deformity. Postoperatively, patients with thick bearings exhibited better Knee Society clinical and pain scores as well as similar functional scores and University of California at Los Angeles activity scores. The overall reoperation rate and 10-year survivorship free of revision were similar between thick and thin bearings (1.7% vs 2.3%; 98.2% vs 96.1%). Patients with thin bearings were twice as likely to require a manipulation under anesthesia postoperatively (P = .02), while there were no failures in the thick bearing group due to aseptic loosening or instability.