El polietileno de alto entrecruzamiento no reduce el desgaste en la artroplastia total de rodilla / Cross-linked polyethylene does not reduce wear in total knee arthroplasty

Objetivo: Comparar dos pares de fricción (metal/polietileno de ultra alto peso molecular [UHMWPE], metal/polietileno de alto entrecruzamiento) mediante análisis cuantitativo y cualitativo de partículas de polietileno en líquido sinovial a los 3 años postintervención en pacientes portadores de prótesis total de rodilla (PTR). Material y métodos: Se llevó a cabo un estudio de cohortes prospectivo, aleatorizado, con evaluación ciega incluyendo 25 pacientes a quienes se intervino de PTR de manera bilateral, con 6 meses de diferencia. A los 3 años postintervención, se realizaron artrocentesis de rodilla a 12 pacientes y se analizaron las partículas de polietileno. Resultados: No se hallaron diferencias significativas en el número de partículas generadas por los diferentes insertos de polietileno a los 3 años tras la implantación de una artroplastia total de rodilla (3.000×: x¯ entrecruzado=849,7; x¯ UHMWPE=796,9; p=0,63; 20.000×: x¯ entrecruzado=66,3; x¯ UHMWPE=73,1; p=0,76). Tampoco existen diferencias significativas entre los 2 tipos de inserto, entre la posibilidad de encontrar partículas de forma elongada (χ2=0,19; p=0,66) ni redonda (χ2=1,44; p=0,23). Sin embargo, la probabilidad de encontrar partículas de forma fibrilar es 3,08 veces mayor en el UHMWPE. Conclusiones: El polietileno altamente entrecruzado no reduce significativamente la generación de partículas de polietileno en aquellos pacientes intervenidos mediante una artroplastia total de rodilla, con muestras a 3 años postintervención

Aim: To compare two different types of inserts: Ultra-high molecular weight polyethylene (UHMWPE) and cross-linked polyethylene with a quantitative and qualitative study of polyethylene wear particles in synovial fluid 3 years after total knee arthroplasty. Material and methods: A prospective, randomized, controlled cohort study with blinded evaluation was carried out on 25 patients undergoing staged bilateral total knee replacement, 6 months apart. Knee arthrocentesis was performed on 12 patients 3 years after surgery, and the polyethylene particles were analyzed. Results: No significant differences were found in the number of particles generated by the two different types of inserts at 3 years from total knee arthroplasty (3,000×: x¯ cross-linked=849.7; x¯ UHMWPE=796.9; P=.63; 20,000×: x¯ cross-linked=66.3; x¯ UHMWPE=73.1; P=.76). Likewise, no differences in the probability of finding elongated (χ2=0.19; P=.66) or rounded (χ2=1.44; P=.23) particles in both types of inserts were observed. However, the probability of finding fibrillar particles is 3.08 times greater in UHMWPE. Conclusions: Cross-linked polyethylene does not significantly reduce the generation of polyethylene particles in patients with total knee arthroplasty, 3 years after the surgical procedure

Cross-linked polyethylene does not reduce wear in total knee arthroplasty. / El polietileno de alto entrecruzamiento no reduce el desgaste en la artroplastia total de rodilla.

AIM: To compare two different types of inserts: Ultra-high molecular weight polyethylene (UHMWPE) and cross-linked polyethylene with a quantitative and qualitative study of polyethylene wear particles in synovial fluid 3 years after total knee arthroplasty. MATERIAL AND METHODS: A prospective, randomized, controlled cohort study with blinded evaluation was carried out on 25 patients undergoing staged bilateral total knee replacement, 6 months apart. Knee arthrocentesis was performed on 12 patients 3 years after surgery, and the polyethylene particles were analyzed. RESULTS: No significant differences were found in the number of particles generated by the two different types of inserts at 3 years from total knee arthroplasty (3,000×: x¯ cross-linked=849.7; x¯ UHMWPE=796.9; P=.63; 20,000×: x¯ cross-linked=66.3; x¯ UHMWPE=73.1; P=.76). Likewise, no differences in the probability of finding elongated (χ2=0.19; P=.66) or rounded (χ2=1.44; P=.23) particles in both types of inserts were observed. However, the probability of finding fibrillar particles is 3.08 times greater in UHMWPE. CONCLUSIONS: Cross-linked polyethylene does not significantly reduce the generation of polyethylene particles in patients with total knee arthroplasty, 3 years after the surgical procedure.