%0 Journal Article
%T Biomechanical testing of a computationally optimized far cortical locking plate versus traditional implants for distal femur fracture repair.
%A Brzozowski P
%A Inculet C
%A Schemitsch EH
%A Zdero R
%J Clin Biomech (Bristol, Avon)
%V 117
%N 0
%D 2024 Jul 21
%M 38936291
%F 2.034
%R 10.1016/j.clinbiomech.2024.106296
%X <B>BACKGROUND: </B>This study experimentally validated a computationally optimized screw number and screw distribution far cortical locking distal femur fracture plate and compared the results to traditional implants.<BR><B>METHODS: </B>24 artificial femurs were osteotomized with a 10 mm fracture gap 60 mm proximal to the intercondylar notch. Three fixation constructs were used. (i) Standard locking plates secured with three far cortical locking screws inserted according to a previously optimized distribution in the femur shaft (n = 8). (ii) Standard locking plates secured with four standard locking screws inserted in alternating plate holes in the femur shaft (n = 8). (iii) Retrograde intramedullary nail secured proximally with one anterior-posterior screw and distally with two oblique screws (n = 8). Axial hip forces (700 and 2800 N) were applied while measuring axial interfragmentary motion, shear interfragmentary motion, and overall stiffness.<BR><B>RESULTS: </B>Experimental far cortical locking plate results compared well to published computational findings. Far cortical locking femurs contained the highest axial motion within the potential ideal range of 0.2-1 mm and a sheer-to-axial motion ratio < 1.6 at toe-touch weight-bearing (700 N). At full weight-bearing (2800 N), Standard locking-plated femurs had the only axial motion within 0.2-1 mm but had an excess shear-to-axial motion ratio. Nail-implanted femurs underperformed at both forces.<BR><B>CONCLUSIONS: </B>For toe-touch weight-bearing, the far cortical locking construct provided optimal biomechanics to allow moderate motion, which has been suggested to encourage early callus formation. Conversely, at full weight-bearing, the standard locking construct offered the biomechanical advantage on fracture motion.