Did you know that bone is the second most commonly transplanted tissue after blood? With more than 2 million procedures taking place every year across the world to heal bone fractures and defects from trauma and disease, bones are in hot demand. In order to help improve the outcomes of these surgeries, scientists have developed a new grafting material from sea urchin spines.
Physicians have various approaches in which to treat bone defects. First, replacement material can be extracted from a patient's own body, tissue can be donated or a synthetic or naturally derived product can be used. However, all of these methods listed have limitations. As an example, current bioceramics (such as hydroxyapatite) that have been used as scaffolds for bone repair have a tendency to be weak and brittle, which can lead to pieces breaking off. Not exactly ideal for usage within a patient where the intent is for a long-term fix. These broken pieces can then move into adjacent soft tissue and incur inflammation.
Recent studies have shown that biological materials such as sea urchin spines appear promising as bone scaffolds because of their porosity and strength. Researchers Xing Zhang, Zheng Guo, Yue Zhu and their colleagues wanted to test this idea in further detail. By using a hydrothermal reaction, the researchers converted sea urchin spines into biodegradable magnesium-substituted tricalcium phosphate scaffolds, all the while maintaining the sea urchin spines' original interconnected, porous structure.
Unlike hydroxyapatite, the scaffolds that were created from the sea urchin spines were able to be cut and drilled to a specified shape and size. Tests that were run on rabbits and beagles showed that bone cells and nutrients could flow through the pores and promote bone function. The spine scaffold was also able to degrade easily and be replaced by the new growth. These researchers feel that these findings could inspire new designs for lightweight materials that could be used for repairing bones.