A car slammed into her motorbike in a horrific accident more than 30 years ago, when she was 24, smashing her leg.

The result was numerous surgeries that left one leg 4.1cm shorter than the other.

She also lost a lot of muscle tissue in one leg after an infection set in during her recovery.

But despite the challenges, Joy has just returned from her very first overseas trip - a four day cycle over the Otago Rail Trail outside Dunedin in New Zealand.

"About four years ago, someone suggested I should have a relatively simple surgery to lengthen my shorter leg, but there were a lot of complications and what should have been two operations turned into five," she said.

"The first titanium rod they put into my leg to lengthen it somehow bent, it must have happened at the gym or when I got back onto a bike for the first time since my accident.

"Then the bone didn't fully take to the new rod and they had to graft bone from my hip, luckily there was enough to take more off because that's where they'd taken bone to graft after my motorbike accident."

Joy's legs are now only 1.1cm different in length and one of her ankles has been fused to stop giving her pain, but that means she has no mobility in one ankle.

She also gets a lot of pain in her knee on the opposite leg from years of overcompensating for the other.

In recovery after her first surgery, Joy decided to make the most of her newly lengthened leg and get back on a bike for the first time since the accident.

She joined the cycling group with the Redlands University of the Third Age (U3A) and has been cycling on and off with them for the last four years, only taking time off to recover from each new surgery.

It was with the U3A that she made her first overseas trip to cycle over the mountains in New Zealand.

"The first day we only cycled half the day, but day two was all day, uphill, with an enormous headwind that blew you backwards when you stopped pedalling, and people kept riding downhill past us with these great big smiles," Joy said.