Fracture prevention by prophylactic femoroplasty of the proximal femur - metallic compared to cemented augmentation

OBJECTIVES:: To compare two different femoral neck augmentation techniques at improving the mechanical strength of the femoral neck.

METHODS:: 20 pairs of human cadaveric femora were randomly divided into two groups. In one group the femora were augmented with a steel spiral; the other group with the cemented technique. The untreated contralateral side served as an intra-individual control. Fracture strength was evaluated using an established biomechanical testing scenario mimicking a fall on the greater trochanter (Hayes fall).

RESULTS:: The peak load to failure was significantly higher in the steel spiral group (p=0.0024) as well as in the cemented group (p=0.001) compared to the intra-individual controls. The peak load to failure showed a median of 3167 N (1825 N-5230N) in the spiral group and 2485 N (1066 N-4395 N) in the spiral control group. The peak load to failure in the cemented group was 3698N (SD ± 1249 N) compared to 2763 N (SD ±1335 N) in the cement control group. Furthermore, fracture displacement was clearly reduced in the steel spiral group.

CONCLUSION:: Femoral augmentations using steel spirals or cement-based femoroplasty are technically feasible procedures. Our results demonstrate that a prophylactic reinforced proximal femur has higher strength when compared to the untreated contralateral limb. Prophylactic augmentation has potential to become an auxiliary treatment option to protect the osteoporotic proximal femur against fracture.