After Van der Westhuizen was diagnosed with motor neurone disease (MND) in July 2011, he was given an 80% chance of surviving two to five years.
MND is any of several neurological disorders that selectively affect motor neurons, the cells that control voluntary muscles of the body. MNDs are neuro-degenerative in nature and cause increasing disability and, eventually, death.
An August 2013 BBC Sport report illustrated the progress of his disease — by then, he was confined to a wheelchair, and his speech had grown increasingly slurred.
In January 2014, he returned to the US to participate in clinical studies with researchers at a hospital in Boston, Massachusetts.
Van der Westhuizen created the J9 Foundation to help other sufferers with MND