Very Distal Femoral Periprosthetic Fractures: Replacement Versus Fixation: A Systematic Review

Objectives: To synthesize all-cause reoperations and complications data as well as secondary clinical and functional outcomes, after the management of very distal femur periprosthetic fractures (vDFPFs) in a geriatric patient population with either a distal femoral locking plate (DFLP) or distal femoral replacement (DFR). Data Sources: MEDLINE, Embase, and Web of Science were searched for English language articles from inception to March 16, 2020, in accordance to the PRISMA guidelines. Study Selection: Studies reporting the management of vDFPFs in adults older than 65 years with either a DFLP or DFR were included. To ensure this review solely focused on very distal femoral periprosthetic fractures, only fractures of the following classifications were included: (1) Lewis and Rorabeck type II or III, (2) Su and Associates' Classification of Supracondylar Fractures of the Distal Femur type III, (3) Backstein et al type F2, and/or (4) Kim et al type II or III. Data Extraction: Three reviewers independently extracted data from the included studies. Study validity was assessed using the methodological index for nonrandomized studies (MINORS), a quality assessment tool for nonrandomized controlled studies in surgery. Data Synthesis: Twenty-five studies with 649 vDFPFs were included for analysis. There were 440 knees in the DFLP group (mean age range: 65.9-88.3 years) and 209 knees in the DFR group (mean age range: 71.0-84.8 years). Because of the literature's heterogeneity, the data were qualitatively synthesized. Conclusions: vDFPFs in the elderly treated with DFR underwent fewer reoperations relative to DFLP (0%-45% vs. 0%-77%, respectively). Time to weight-bearing was observably shorter in DFR studies relative to DFLP studies. Functional outcomes and postoperative range of motion indicated a trend for DFLP knees to outperform DFR knees. Future research should include prospective studies and cost-effectiveness evaluations to better understand the utility of DFR for these fractures.