Cemented and uncemented (press-fit) fixation in distal femur replacement (DFR): A systematic review and meta-analysis

Distal femur replacement (DFR) is an important salvage procedure in the treatment of revision arthroplasty with severe bone loss, supracondylar femur fractures in the elderly, periprosthetic distal femur fractures, and tumor reconstruction. DFR can be implanted using cement or with a press-fit technique. This systematic review aims to evaluate the outcomes of distal femur replacement with cemented and uncemented fixation. A search was conducted across MEDLINE/Pubmed, Wiley, Cochrane Central, Google Scholar, Web of Science, Clinicaltrials.gov and Embase databases. The search used a combination of keywords and Medical Subject Heading (MeSH) terms. Titles and abstracts were screened for eligibility for inclusion criteria. Full texts were screened and included if they met eligibility criteria. Demographics and results of the studies were extracted from the articles that met inclusion criteria. Pooled meta-analysis was completed to compare results across the studies. Thirty-nine studies were included in this systematic review, with thirty studies meeting criteria for meta-analysis. DFR was completed for tumor reconstruction, distal femur fractures, and revision arthroplasty. Studies reported functional outcome measures, complications, rates of loosening, and survivorship data. Meta-analysis revealed that the press-fit DFR had decreased rates of loosening (OR: 0.58, CI: 0.40-0.85, p=0.005), decreased overall complications (OR: 0.72, CI: 0.58-0.88, p=0.001), and less chance of failure (OR: 0.34, CI: 0.27-0.43, p<0.001) when compared with cemented DFR. Uncemented (press-fit) DFR showed decreased rates of loosening, rates of failure, and overall complications when compared with cemented DFR in this pooled analyses. MSTS scores were higher in the cemented group. Comparative studies currently remain scarce, and additional comparative literature should be completed to further investigate these possible findings.