The prevention of hip fractures is a desirable goal to reduce morbidity, mortality, and socio-economic burden. We evaluated the influence on femoral strength of different clinically applicable cementing techniques as ''femoroplasty.'' Twenty-eight human cadaveric femora were augmented by means of four clinically applicable percutaneous cementing techniques and then tested biomechanically against their native contralateral control to determine fracture strength in an established biomechanical model mimicking a fall on the greater trochanter. The energy applied until fracture could be significantly increased by two of the methods by 160% (53.1 Nm vs. 20.4 Nm, p < 0.001) and 164% (47.1 Nm vs. 17.8 Nm, p ¼ 0.008), respectively. The peak load to failure was significantly increased by three of the methods by 23% (3818.3 N vs. 3095.7 N, p ¼ 0.003), 35% (3698.4 N vs. 2737.5 N, p ¼ 0.007), and 12% (3056.8 N vs. 2742.8 N, p ¼ 0.005), respectively. The femora augmented with cemented double drill holes had a lower fracture strength than the single drilled ones. Experimental femoroplasty is a technically feasible procedure for the prophylactic reinforcement of the osteoporotic proximal femur and, hence, could be an auxiliary treatment option to protect the proximal femur against osteoporotic fractures. ß

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 with the untreated contralateral limb. Prophylactic augmentation has potential to become an auxiliary treatment option to protect the osteoporotic proximal femur against fracture.

The validity of dual energy X-ray absorptiometry (DXA) and peripheral quantitative computed tomography (pQCT) measurements as predictors of pertrochanteric and femoral neck fracture loads was compared in an experimental simulation of a fall on the greater trochanter. 65 proximal femora were harvested from patients at autopsy. All specimens were scanned with use of DXA for areal bone mineral density and pQCT for volumetric densities at selected sites of the proximal femur. A three-point bending test simulating a side-impact was performed to determine fracture load and resulted in 16 femoral neck and 49 pertrochanteric fractures. Regression analysis revealed that DXA BMD trochanter was the best variable at predicting fracture load of pertrochanteric fractures with an adjusted R 2 of 0.824 (p < 0.0001). There was no correlation between densitometric parameters and the fracture load of femoral neck fractures. A significant correlation further was found between body weight, height, femoral head diameter, and neck length on the one side and fracture load on the other side, irrespective of the fracture type. Clinically, the DXA BMD trochanter should be favored and integrated routinely as well as biometric and geometric parameters, particularly in elderly people with known osteoporosis at risk for falls. Keywords: osteoporosis; femur fracture; BMD; pQCT; DXA Hip fractures are a cause of significant morbidity and mortality worldwide and are a substantial economic burden.1,2 About 54% of women aged 50 years or older will have an osteoporotic fracture during their lifetime. Furthermore, approximately 4% of the patients older than 50 years with a hip fracture die in the hospital and 24% die within 1-year after the hip fracture. 4 Thus, the prevention of osteoporotic femur fractures is of increased significance to reduce morbidity and mortality on the one hand and socio-economic burden on the other hand.At present, areal bone mineral density (aBMD) as obtained from dual energy X-ray absorptiometry (DXA) is the best established clinical parameter for diagnosis and follow-up of osteoporosis. 5,6 It is widely used as a predictor of fracture risk of the hip although there is considerable overlap in the densitometry measurements of individuals who have fractured and those who have not. 7 In addition, over the past years the measurement of volumetric bone mineral density (vBMD) by peripheral quantitative computed tomography (pQCT) gained more and more interest in the field of basic research. Several ex vivo studies indicate that vBMD measured by pQCT has the highest predictive value for mechanical strength of cancellous bone of the proximal and diaphyseal femur. [8][9][10] In this context, there is little data available comparing the predictive value of areal and volumetric BMD measuring techniques on the mechanical strength of the proximal human femur. Moreover, recent publications comparing the predictive value of different bone density measuring techniques on the femoral fracture strength significantly vary for the me...