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Background Elastomer femoroplasty is a novel and experimental approach in the prevention of hip fracture surgery. Previously, we published the results of an in vitro cadaveric experiment in which we showed a significant reduction of fracture displacement in treated femurs. The aim of the present study was to establish the failure loads and inter‐fragmentary movement of fractured, elastomer femoroplasty treated femurs during cyclic loading. Methods 16 cadaveric femurs were treated with elastomer femoroplasty and fractured in a simulated fall configuration. Each specimen underwent 10 cycles with a preload of 50 N, starting with a peak load of 250 N followed by 10 cycles of 500 N and continued with 500 N increments. The crosshead speed was 2 mm/s. The failure load, the number of completed cycles, and crosshead extensions were recorded. Findings The mean failure load was 2709 N (SD 1094). The number of completed cycles until failure was 60 (SD 22). The mean translation during maximum loading was 5.25 mm (SD 0.9). At 1500 N (two times the bodyweight of a 75 kg individual) the extension was 3.16 mm. Interpretation Preventive elastomer femoroplasty leads to the stabilization of the proximal femur after fracture. In a single leg stance configuration, cyclic loading with mean failure loads that well exceed the peak loads during normal gait is feasible.

The purpose of this study was to test femur strength and the ability to prevent fracture displacement of two minimal invasive Elastomer femoroplasty techniques. Methods A total of sixteen fixed human cadaveric femur pairs were used. From each pair one femur was randomly assigned for Elastomer femoroplasty. In these femora we drilled a 3.5 mm entrance in the lateral cortex. Cavities for the Elastomer were created by: group A, balloon and group B an excentric drill. All femora were fractured by simulating a fall on the greater trochanter. Neck-shaft-angles on plain anterior posterior radiographs were measured to determine fracture displacement. Findings There was no significant difference in fracture load between controls and treated femora for group A, 2904 N (SD 1091) versus 2803 N (SD 627) and group B, 2773 N (SD 747) versus 2597 N (SD 834). In group A the mean displacement was 35° (SD 14) for the control femora and 3° (SD 2) for the treated femora ( P P Interpretation The results of this study show that minimal invasive Elastomer femoroplasty prevents fracture displacement of the proximal femur. We found no significant compromise in load-to-fracture after minimal invasive balloon or excentric drill femoroplasty.

Background Prevention of hip fracture surgery in the elderly imposes great benefit for patient care as well as for society. The incidence of contra-lateral, second hip fractures after hip fracture surgery is as high as 20%. Augmentation of the contra-lateral proximal femur with silicone femoroplasty during hip fracture surgery of the ipsilateral hip could be a new preventive strategy. This study compared the degree of dislocation after a controlled induced fracture between treated and control cadaver femora. Methods Ten paired cadaver femora were randomly assigned for silicone femoroplasty and biomechanically tested for fracture load and dislocation against their native contra-lateral control. A load testing machine was used for fracture induction. All femurs were first fractured in a simulated fall configuration followed by dislocation in a “single leg stance” configuration. Dislocation was accessed using the AO-classification and measuring the Caput–Collum–Diaphysis angle. Findings Fracture loads were approximately 10% lower in the treated group ( P = 0.304). Forces needed to dislocate the proximal femur fractures did not significantly differ in both groups nor did the fracture type and AO-classification. All treated femurs showed complete reposition according to Caput–Collum–Diaphysis angle after dislocation versus only two of the controls ( P Interpretation From the results of this study we conclude silicone femoroplasty stabilizes the proximal femur by restoring hip geometry according to the Caput–Collum–Diaphysis angle after fracture. Future improvements in minimal invasive excavation and injection could make silicone femoroplasty an attractive alternative strategy in the prevention of hip fracture surgery in the growing population of low-demand, elderly patients.

Zinc (Zn) blocks caspase-3 activation in cardiac allografts and therefore may synergistically decrease apoptosis along with cyclosporine (CsA), which inhibits mitochondrial release of cytochrome c. Simultaneous treatment of rat recipients of heterotopic heart transplants with zinc chloride (ZnCl(2)) thus may allow lower doses of CsA for immunosuppression.PVG (RT1(c)) rat hearts were transplanted heterotopically into the abdomen of ACI (RT1(a)) rats. Group 1 (n = 15) rats received no treatment. Group 2 rats (n = 8) received 2 mg/kg/day CsA (sub-therapeutic dose) by oral gavage. Group 3 rats (n = 9) received 2 mg/kg/day oral CsA in addition to 1 mg/kg/day sub-cutaneous ZnCl(2) delivered by osmotic pump. All rats were imaged using Annexin V-bound (99m)Technetium ((99m)Tc-Annexin V) on post-operative Day 4 and subsequently killed. Annexin V avidly binds apoptotic cells in vivo. Region of interest per whole body (WB) data were calculated using the images. The allograft survival study was conducted with n = 11, 6, and 5 in control, CsA, and CsA+Zn groups, respectively. Finally, percentages of allografts that reached tolerance were measured in both CsA-only and CsA+Zn groups (n = 8 each).Zinc chloride had an additive effect with CsA on apoptotic blockade and graft survival. The regions of interest per WB uptake of (99m)Tc-Annexin V were 2.43% +/- 0.37%, 2.08% +/- 0.52%, and 1.49% +/- 0.29%*, and acute survivals were 6.4 +/- 1.7, 7.2 +/- 2.1, and 11.2 +/- 2.5* days for control, CsA, and CsA+Zn groups, respectively (*p0.001 vs controls). In addition, 87.5% of allografts became tolerant and survived for 90 days in the CsA+Zn group compared with only 37.5% in the CsA-only group (p = 0.049).Zinc-mediated reduction of apoptosis served as an effective adjunct immunosuppressive therapy to CsA in a rat model of cardiac transplantation.