Background and purpose The most frequently used bones for mechanical testing of orthopedic and trauma devices are fresh frozen cadaveric bones, embalmed cadaveric bones, and artificial composite bones. Even today, the comparability of these different bone types has not been established.Methods We tested fresh frozen and embalmed cadaveric femora that were similar concerning age, sex, bone mineral density, and stiffness. Artificial composite femora were used as a reference group. Testing parameters were pullout forces of cortex and cancellous screws, maximum load until failure, and type of fracture generated.Results Stiffness and type of fracture generated (Pauwels III) were similar for all 3 bone types (fresh frozen: 969 N/mm, 95% confidence interval (CI): 897–1,039; embalmed: 999 N/mm, CI: 875–1,121; composite: 946 N/mm, CI: 852–1,040). Furthermore, no significant differences were found between fresh frozen and embalmed femora concerning pullout forces of cancellous screws (fresh frozen: 654 N, CI: 471–836; embalmed: 595 N, CI: 365–823) and cortex screws (fresh frozen: 1,152 N, CI: 894–1,408; embalmed: 1,461 N, CI: 880–2,042), and axial load until failure (fresh frozen: 3,427 N, CI: 2,564–4290; embalmed: 3,603 N, CI: 2,898–4,306). The reference group showed statistically significantly different results for pullout forces of cancellous screws (2,344 N, CI: 2,068–2,620) and cortex screws (5,536 N, CI: 5,203–5,867) and for the axial load until failure (> 7,952 N).Interpretation Embalmed femur bones and fresh frozen bones had similar characteristics by mechanical testing. Thus, we suggest that embalmed human cadaveric bone is a good and safe option for mechanical testing of orthopedic and trauma devices.

Purpose Reduction and intramedullary fixation of subtrochanteric fractures is often challenging. Osteosynthesis frequently fails and a higher rate of non-unions is found.

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BackgroundWhole-body multislice computed tomography (WB-MSCT) has become an important diagnostic tool in the early treatment phase of severely injured patients. The optimal moment of WB-MSCT’s use during this treatment phase remains unclear. Many trauma centers use WB-MSCT in addition to conventional radiographs, while some trauma centers use WB-MSCT as the only radiological tool. The aim of this study was to determine the differences between these two protocols and to answer the question of whether conventional radiographs can still be used in the safe treatment of polytrauma patients.MethodsPatients from the TraumaRegister DGU® with an injury severity score (ISS) of ≥16 were included. Group I received conventional radiographs and focused assessment with sonography in trauma (FAST) prior to a WB-MSCT, and group II received an initial WB-MSCT and FAST. Both groups were compared concerning treatment time and outcome.ResultsA total of 3,995 patients in group I were compared to 4,025 patients in group II. There were no differences in ISS (29.97 vs. 29.94), gender (male: 73.5% vs. 72.8%), age (45.47 vs. 45.12 years), or calculated mortality (21.41% vs. 21.44%). Time needed in the resuscitation room was slightly longer in group I (72 vs. 64 min); the durations until admittance to the ICU and arrival to the OR were not significantly different between the groups. There was no difference in mortality (18.2% vs. 18.4%) or the standardized mortality ratio (SMR) (0.85 vs. 0.86).ConclusionsWB-MSCT plays an inherent role in the treatment of multiple-injured patients. However, the use of WB-MSCT as the only diagnostic method in the resuscitation room is not needed. Conventional radiographs and FAST followed by WB-MSCT can be performed in the early resuscitation phase without impairing patient outcomes. This approach enables the emergency room team to perform life-saving procedures - chest-tube insertion, laparotomy, cardiopulmonary resuscitation -immediately and simultaneous. Nevertheless, randomized multi-center trials are needed to determine the comparability and effectiveness of these algorithms.