I used to race yachts with the Unit Paymaster. He was a retread gunner. He had been in hospital for something (I forget - come on I was listening to an officer's stories ffs) and found himself next to a crab who'd been in traction for months.
The crab had been doing a practice scramble in a Lightning, rotated too quickly and dragged the bottom engine along the runway. Popped out courtesy of Mr Martin Baker at zero feet. In those days ejectors were so violent that they compressed the spine. He spent a short while in hospital and was cleared to fly.
He was invited to fly another Lightning from East Anglia to CrabG and got halfway across the North Sea when he met a thunderstorm, suffered a flameout and had to punch again.
When the Paymaster met him they were trying to restore the four lost inches to his height lost by spine compression.