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

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.

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.