Comparison of bone wax and chitosan usage on post-sternotomy bone healing.

Background: Sternotomy is a standard approach performed in almost every surgical procedure on the heart and mediastinum. Effective hemostasis of the sternum is required to keep the operative field dry, avoid excessive blood transfusions during surgery, and prevent reoperation due to massive postoperative bleeding, which can further increase morbidity and mortality in patients. Bone wax is a mechanical hemostat commonly used after sternotomy and has been known to affect bone healing, trigger chronic inflammatory reactions, and increase the rate of infection. The application of chitosan, which has intrinsic hemostat ability, as hemostatic material is believed to improve bone healing following sternotomy. This study aimed to compare the effectiveness of bone wax and chitosan on bone healing after sternotomy.
Methods: Median sternotomies were performed on 2 groups of New Zealand White rabbits. Each group of 16 animals received either bone wax or chitosan powder as hemostatic material. The degree of bone healing, the number of foreign-body giant cells, and the number of osteoblasts were evaluated after 6 weeks.
Results: Radiographs showed that significantly more animals in the chitosan group had total sternal healing ( p  = 0.033). Histopathology revealed that the number of foreign-body giant cells was significantly less ( p = 0.036) and the number of osteoblasts was significantly greater ( p  < 0.0001) in the group of animals that received chitosan.
Conclusion: The use of chitosan as hemostatic material can promote better bone healing compared to bone wax.