Background : Cementless total knee arthroplasty (TKA) has become increasingly popular. Some surgeons are concerned about pain, implant stability, and metal-backed patellar component survivorship. This study investigated the outcomes of cementless compared with cemented TKA in bilateral cases.

Methods: We randomized 80 knees in 40 osteoarthritic knee patients who underwent bilateral TKA with patellar resurfacing under one anesthesia. All participants received cementless prostheses in one knee and cemented prostheses in the other. The outcomes were knee function measured by the forgotten joint scores, modified Western Ontario and McMaster Universities Osteoarthritis Index, knee ranges of motion, pain levels, operative times, radiographic outcomes, and complications. All knees were followed for a minimum of 2 years (2 to 3 years).

Results:  Cementless and cemented TKA had similar functional outcomes in forgotten joint score (97 ± 5 versus 98 ± 3 points, P = .52), modified Western Ontario and McMaster Universities Osteoarthritis Index score (3 ± 4 versus 3 ± 2 points, P = .96), and ranges of motion (134 ± 7° versus 134 ± 7°, P = .16). The postoperative pain was also similar (P > .05). There were 4 cementless patellar components had superior migration for an average of 3.5 mm (range, 1.77 to 4.16) without loosening. The mean time of migration was 4 (range, 2 to 6) weeks.

Conclusions: Cementless TKA had similar functional outcomes and recovery patterns compared with cemented TKA. However, there was concern of cementless component migration at patellae.