[Biomechanical evaluation of dynamic hip screw with bone cement augmentation in normal bone].
OBJECTIVE
To investigate the effects of augmentation with bone cement on the biomechanics of the dynamic hip screw (DHS) fixation in the intertrochanteric fracture specimen that has a normal bone density.


METHODS
Twenty-four matched pairs of the embalmed male upper femora (48 sides) were used to make the specimens of the intertrochanteric fracture of Type A2. All the specimens were fixed with DHS. The right femur specimen from each pair was fixed by augmentation with DHS (the augmentation group) and the left femur specimen was fixed with the conventional fixation (the control group). The biomechanical tests on the bending stiffness and the torsional stiffness were performed with the servohydraulic testing machine in the two groups.


RESULTS
The maximum load and the maximum torque were 3852.1602 +/- 143.6031 N and 15.5 +/- 2.6 Nm in the augmentation group and 3702.9667 +/- 133. 860 1 N and 14.7 +/- 3.4 Nm in the control group. There was no significant difference in the biomechanical effects between the two groups (P > 0.05).


CONCLUSIONS
The augmenting fixation with bone cement in the intertrochanteric fracture specimen with a normal bone density has no significant effect on the strength of the DHS augmentation or on the overall stability of the fractured bone.
Li
Ning
N
Department of Orthopedics, Third Hospital of Shijiazhuang, Shijiazhuang Hebei, 050011, PR China. eastln@yahoo.com.cn
Peng
Aqin
A
Chai
Yi
Y
D000328:Adult; D001696:Biomechanical Phenomena; D001843:Bone Cements; D015519:Bone Density; D001863:Bone Screws; D002102:Cadaver; D005593:Fracture Fixation, Internal / Q000295:instrumentation / Q000379:methods*; D006620:Hip Fractures / Q000601:surgery*; D006801:Humans; D008297:Male; D013718:Tensile Strength; D016474:Weight-Bearing
D001843:Bone Cements