About one in ten Australians has a lumbosacral transitional vertebra, a difference in the bones at the base of the spine that is present from birth. Most never know. In a minority it causes persistent pain in the lower back, buttock or hip that is treated for years as ordinary strain, and the person is often told that the scans are fine.

This guide is for the partner, parent, child, sibling, housemate or friend of someone with the condition. It explains in plain terms what the anatomy is, why the diagnosis took so long, what the pain is like from the inside, and what diagnosis and treatment involve, including what surgery can and cannot do. It sets out what the Australian patient literature says helps and what does not, how to explain the condition to children, what to expect around surgery, how the Australian system and its costs bear on a family, and how carers look after themselves.

Every clinical figure is drawn from the published evidence, and the notes at the end say what could and could not be verified.