Effect of long-term preservation on the mechanical properties of cortical bone in goats

Abstract

Background and purpose Bones used in mechanical studies are frequently harvested from human cadavers that have been embalmed in a buffered formaldehyde solution. It has been reported that formaldehyde fixation or freezing hardly affects the mechanical properties of bone after a storage period of several weeks. However, human cadaver bones are usually stored for longer periods of time before use. We therefore investigated the effects of long-term embalming or freezing on the mechanical properties of cortical bone.Methods After 5 different storage periods (ranging from 0 to 12 months), goat femora and humeri were used to evaluate the effect of embalming and freezing on torsion, and on bending stiffness and strength. The effect on hardness and bone mineral density (BMD) was also evaluated.Results Even after 1 year, no statistically significant differences could be found in stiffness, strength, and energy absorption when we compared embalmed or frozen bones to a fresh reference group. In addition, although we found no significant change in BMD, there appears to be a tendency to increasing hardness.Interpretation We found that there was no effect on the mechanical properties of bone after storage periods of 1 year. We conclude that embalmed or frozen bones can safely be used for mechanical testing, at least for storage periods of up to one year.

Unique stability of femoral neck fractures treated with the novel biplane double-supported screw fixation method: A biomechanical cadaver study

“…Previous studies concluded that Table 2 Axial stiffness (kN/mm) and failure load (kN) of the specimens in the four study groups (mean AE SEM). Table 3 Interfragmentary fracture displacement (mean AE SEM, mm) along the diaphyseal axis at 100-cycle intervals and 100-N loads during cyclic testing of fresh-frozen (FRZ) femora instrumented with CFIX or BDSF and laterally inclined at 78. both these bone types demonstrate similar mechanical characteristics [26][27][28]. The baseline values for AP bending stiffness, axial stiffness and BMD of all intact femora, obtained in our study, are comparable between the FRZ and EMB specimens, which is consistent with these previous findings [26][27][28] and justifies the use of both bone types in the current study.…”

“…The use of fresh-frozen and embalmed femora in the current study was based on literature data demonstrating that both bone types have similar mechanical characteristics and are recommended for biomechanical testing of orthopaedic and trauma devices [26][27][28]. Consequently, using these two types of femora was not expected to be a confounder for different mechanical behaviour between the study groups.…”

Effect of Storage Temperature on Allograft Bone

“…Elasticity of bone is affected by mineralization while plastic behavior is related to collagen [41,42] and the strength of the bone graft depends on the interaction of mineral content and collagen [42]. Other studies found no influence of deep freezing at -20 °C onto the biomechanical properties neither of goat bone within 12 months of storage [43] nor of rat bone after 2 weeks [3]. No adverse effect onto biomechanical features was shown at lower temperatures of -70 and -196 °C [3,42].…”

Using of Bleaching Powder for Cleaning Embalmed Cadaveric Bones

“…16 It was seen that there was no effect on the mechanical properties of bone after storage periods of one year and these bones can be used for mechanical testing at least for storage periods of up to one year. 17 Bacterial maceration in water or soil was one of the oldest documented techniques for defleshing 18,19 but these methods were more expensive. In our present study, it was observed that bones were neatly cleaned by burial method as well as by using bleaching powder solution as a source of chlorine solution.…”