Biomechanical comparison of patellar cementing techniques in total knee arthroplasty: a biomechanical study.

OBJECTIVES

The aim of this study was to biomechanically compare three different cementing techniques for patellar component fixation in total knee arthroplasty.  MATERIALS AND METHODS: Synthetic patellar bone model (Selbones© Research Laboratory, Kayseri, Turkey) was implanted with an all-polyethylene universal dome patellar component (Trauson universal dome, Stryker, Changzhou, China) using bone cement (Surgical Simplex P, Stryker, Limerick, Ireland). The test specimens were divided into three groups according to the cementing technique. Group 1 was named as "partial cementing", Group 2 as "full cementing" and Group 3 as "modification" technique. Modification technique was performed with a 50 cc injector. After fixation of the materials, the strength of fixation was tested biomechanically by applying force with isolated scissors produced using a tensile compression testing machine (UVE, Bursa-Turkey). Curves and peak stress pressures were statistically analyzed to determine which cementing technique provided the best fixation strength.

RESULTS

The mean peak stress pressure of a total of 30 test specimens was 1305.86 (± 24.72) N (Newton) and these values were determined as 1013.00 (± 24.72), 1334.60 (± 37.17) and 1570.00 (± 26.56) N for group 1, group 2 and group 3, respectively (p < 0.001). A statistically significant difference was found in the multiple comparisons of all groups with each other and fixation of group 3 was found to be better than group 1 and 2 (p < 0.001).  CONCLUSION: The modified cementing technique demonstrated superior biomechanical fixation strength compared to conventional methods in this in vitro study. This low-cost and easily applicable technique may help reduce patellar component-related complications and warrants further evaluation in clinical settings.