On January 1, 2000 after celebrating the New Year in Brazil with friends on a remote beach, Bruno Guez went for a swim. As he dived into the water, his head hit the sand. He noticed a sudden inability to move and he started drowning.

Fortunately for him, he managed to hold his breath and his friends came to the rescue, noticing something was not normal.

He was diagnosed with a fractured fifth vertebrae, which had squeezed his spinal cord. ...