Hybrid fixation versus full-cemented or full-cementless fixation in total knee arthroplasty: Systematic review and meta-analysis of comparative studies.

Objective: Hybrid fixation is one alternative to full-cemented fixation in total knee arthroplasty (TKA) with theoretical advantages. Hybrid fixation may offer the advantages of cementless femoral fixation, while also avoiding the problem of tibial loosening in full-cementless TKA. The purpose of the study is to determine whether hybrid TKA may perform comparably to or better than full-cemented and full-cementless TKA.

Methods: We searched the MEDLINE, EMBASE and Cochrane Library databases through September 2018 for randomized controlled trials and observational studies comparing outcomes of hybrid versus full-cemented or full-cementless fixation techniques. Outcomes of interest included aseptic loosening, overall reoperation rate, infection, radiolucent lines and operating time. Data were pooled with the Mantel-Haenszel random effects model.

Results: We included 14 studies with follow-up ranging from 2.7 to 9.6 years in our quantitative analysis, of which 7 studies compared hybrid fixation with full-cemented TKA and another 7 compared hybrid fixation with full-cementless TKA. Combined data revealed that the hybrid fixation group had a similar rate of aseptic loosening compared with cemented (P = 0.19) and cementless (P = 0.49) groups. There was no difference with respect to other outcomes, including overall reoperation rate, infection, radiolucent lines and operating time between groups.

Conclusion: Hybrid, cementless and cemented TKAs have comparable mid-term results as it pertains to aseptic loosening, overall reoperation, infection, radiolucent lines and operating time. Further comparative studies are needed to investigate these potential effects over the long-term.