A Five-Year Retrospective Comparative Study of Clinical and Radiographic Outcomes in Total Knee Arthroplasty Using Biomet vs. Palacos Cement Fixation

Background: Cemented fixation remains the standard for total knee arthroplasty (TKA), with Palacos® R considered the gold standard bone cement. However, more cost-efficient alternatives, like Biomet Bone Cement® (BBC), require evaluation to confirm comparable outcomes. This retrospective 5-year study compares the clinical safety, performance, and radiographic outcomes of BBC versus Palacos-R in primary TKA, highlighting BBC’s potential as a comparable, cost-effective option amid the increasing cost of outpatient surgeries. Methods: This is a single-center, retrospective study of 128 consecutive patients undergoing primary TKA, evaluated over 5 years. The first 64 patients received Palacos-R, and the subsequent 64 patients received BBC. Radiographic outcomes, including cement gaps, radiolucency, periprosthetic osteolysis, and subsidence, were assessed using the Knee Society Radiographic scheme at immediate post-operative, 6-month, 1-year, 3-year, and 5-year intervals. Clinical outcomes were measured using the Knee Society Score (KSS) and the University of California Los Angeles Activity (UCLA) score. Statistical analyses included chi-square, Fisher’s exact tests, and t-tests (p < 0.05). Results: Cement gaps were significantly higher in the Palacos-R cohort at immediate postop (p = 0.0002) and 1-year (p = 0.0003), with no significant difference at 3 and 5 years. Radiolucency was non-progressive (<2 mm) in both cohorts. KSS was significantly higher in the Palacos-R group at 6 months, 1 year, and 3 years (p < 0.001), but equivalent at 5 years (p = 0.42). UCLA scores showed no differences. No revisions were required in either cohort. Conclusions: While BBC demonstrated comparable radiographic stability and clinical outcomes to Palacos at 5 years with no revisions in either cohort, the absence of preoperative KSS and UCLA scores is a major limitation that prevents adjustment for baseline function and limits interpretation of the early postoperative KSS differences.