Cemented Total Knee Arthroplasty Shows Less Blood Loss but a Higher Rate of Aseptic Loosening Compared With Cementless Fixation: An Updated Meta-Analysis of Comparative Studies.

BACKGROUND: The aim of this study was to update the current evidence on functional outcomes, complications, and reoperation rates between cemented and cementless total knee arthroplasty (TKA) by evaluating comparative studies published over the past 15 years.

METHODS: The PubMed, MEDLINE, Scopus, and the Cochrane Central databases were used to search keywords and a total of 18 studies were included. Random and fixed effect models were used for the meta-analysis of pooled mean differences (MDs) and odds ratios (ORs).

RESULTS: A total of 5,222 patients were identified with a mean age of 64.4 ± 9.4 and 63 ± 8.6 years for the cemented and cementless TKA groups, respectively. The mean follow-up was 107.9 ± 30 and 104.3 ± 10 months for the cemented and cementless TKA groups, respectively. Cemented TKA showed a significantly greater postoperative Knee Society Score (MD = -0.95, 95% CI [-1.57, 0.33], P = .003) and range of motion (MD = -1.09, 95% CI [-1.88, -0.29], P = .0007), but no differences in other outcome scores were found. The incidence of periprosthetic joint infection, radiolucent lines, instability, and polyethylene wear was also comparable. Cemented TKA showed less perioperative blood loss (SMD = -438.41, 95% CI [-541.69, -35.14], P < .0001) but a higher rate of manipulation under anesthesia (OR = 3.39, 95% CI [1.64, 6.99], P = .001) and aseptic loosening (OR = 1.62, 95% CI [1.09, 2.41], P = .02) than cementless TKA. No differences were found in terms of the reoperation rate.

CONCLUSION: When cemented and cementless fixations are compared in primary TKA, comparable functional outcomes and reoperation rates can be achieved. Cemented TKA showed less blood loss but a higher rate of manipulation under anesthesia and aseptic loosening.