Provided there is no spinal cord damage, the best way to treat the fracture is by immobilization of the spine both above and below the fracture until healed.
Generally the spine must be stabilized first. Sometimes surgery can be done to help correct the fracture, but it depends on the severity of the fracture.
A L5 vertebrae fracture requires individualized treatment. The type of injury ,nerve compression,anatomical variations should be taken into consideration first. Take complete bedrest and allow bony reunion.