Developing Protocols to Histologically Assess Murine Bones

Our current study employs a burr-hole fracture model on murine tibias. We are using this study in investigating the role of p21 in improving bone healing outcomes. It is important to view the precise area of injury (0.7mm) in these bones. This requires embedding these samples in paraffin wax and then cutting thin slices (10um) using a microtome. We have encountered issues with samples cracking and tissues being sliced. Our samples often ‘crumble’ under the microtome, and the slices from these samples do not contain the required bone needed. This can be attributed to several factors, such as the samples being too old, or cracking as a because of not receiving enough moisture. As a result, we have used a variety of methods to combat these issues. These methods range from remoistening the sample by placing it on ice, to the complete re-embedding of the sample itself. Our current method, however, is our focus- we intend to repeat the entire process with new samples to assess its effectiveness and determine if there are any issues with the samples being too old. The results from this project will help us reform our protocols to successfully implement histological techniques to assess bone healing