Despite rehabilitation, her right arm aches with every swing motion, as there is a 22.5cm titanium rod in the bone.
Schrader also suffered some memory loss and can still feel pain throughout her body.
Nonetheless, she is determined to finish the walk today in around seven hours, given it was in May of 2004 she completed the course in 6hr 17m in her first comeback from adversity.
Having run in six marathons in 2000, Schrader collapsed while playing a game of darts with her husband. It was discovered she had a golf ball-sized tumour in her head, which had affected her movement so badly that walking to the front gate was a challenge.
The tumour was removed in 2001, with Schrader spending more than two months in a wheelchair, learning how to take steps because she had no movement in her left foot. The after-effects included seizures, which happened every 12-14 days, although she learned to control them.
Although she is now a walker, just being out there again in her second comeback means so much.
"I've just got to be doing this," she said. "I was sitting inside [my house] feeling sorry for myself and crying over everything I had been through.
"But training for this marathon has made me strong again.
"Getting to that finish line will be pretty emotional. There will be tears of happiness that I've been able to re-do it.
"I've had to fight back and train so hard to get my fitness back."