Comparison of lyophilization, and freezing in honey as techniques to preserve cortical bone allografts used to repair experimental femoral defects in domestic adult cats

Abstract

Cats with orthopedic conditions are a prominent part of the clinical work of veterinary. Conditions such as comminuted fractures, bone tumors and non-unions are often difficult to repair and may require the use of bone grafts for treatment. This study evaluated cortical bone allografts preserved in honey, frozen or lyophilized for correcting long bone defects created in the diaphysis of the right femur of domestic cats (n=24). In the control group (n=6), the defect was repaired using autogenous cortical bone graft. In the remaining animals (n=6/group), the defect was repaired with cortical bone allografts preserved in honey, frozen or lyophilized. Success of graft incorporation and length of time for consolidation were assessed through clinical, radiographic and histological evaluations performed up to 180 days. In the control, frozen, honey and lyophylized groups, respectively, success of graft incorporation was 91.6%, 83.3%, 75%, and 25%, with corresponding mean length of time for consolidation of 83.1, 78, 105 and 120 days. Incorporation percentage in the lyophilized group was significantly lower than in the frozen and control groups. In conclusion, bone grafts preserved in honey or frozen were effective for repairing cortical defects in the femurs of cats as compared to autogenous cortical bone grafts.

The biomechanical and biological effect of supercooling on cortical bone allograft

“…Each criterion for radiologic evaluation was scored ( Table 1 ). This scoring system was devised based on previous studies [ 9 32 33 ]. The criterion for radiographic callus formation was established as bone bridging around the fracture line.…”

“…Various storage techniques for cortical allografts have been developed, including preservation by freezing, lyophilization, honey, and glycerol [ 8 9 10 ]. Traditional preservation techniques, such as freezing and lyophilization, have been reported to result in the successful incorporation of bone allografts; however, these techniques have the potential to compromise structural stability as a result of the freeze-thaw or lyophilization process [ 11 12 13 14 ].…”

“…The biomechanical properties and clinical applications of the aforementioned cortical bone allograft preservation techniques have been widely investigated [ 9 17 29 30 ]. However, only a few studies have evaluated relative differences in the biomechanical and biological properties of various preservation methods [ 8 9 10 ].…”

“…The biomechanical properties and clinical applications of the aforementioned cortical bone allograft preservation techniques have been widely investigated [ 9 17 29 30 ]. However, only a few studies have evaluated relative differences in the biomechanical and biological properties of various preservation methods [ 8 9 10 ]. In particular, no previous study has applied supercooling technology to bone tissue preservation and evaluated the impact of supercooling on the bone union of cortical bone allografts.…”

Bone graft in veterinary orthopedics: Review

“…O mel é considerado bom conservador ósseo, eficaz contra reações imunológicas, de baixo custo e facilmente encontrado. Porém, cuidados devem ser tomados quando a sua utilização, como por exemplo, a exposição à luz solar e altas temperaturas que prejudicam suas funções antimicrobianas e antibacterianas (Ferreira et al, 2012).…”