I am currently sectioning the tail of a lizard at 50 microns using vibratome. Each tail is previously fixed in 4% PFA and 0.1% EDTA and embedded in 5% agarose:PBS. Everytime I section the spinal cord falls out. I believe it is due to the epidural space (fatty tissue) between the vertebra and the connective tissues surrounding the spinal cord. Can anyone suggest other reasons why this may be occuring or how I can adjust my technique? Thanks?