The surgery was explained to her in detail, Billman signed consent forms, fasted that night, and her husband Eddie stayed in a Hamilton motel so he could help his wife get ready for theatre at 6.30am the next day.
But before it could go ahead the Billmans were met by the surgeon.
"He came and examined me and said 'No we won't be operating'. I was just so angry."
Two days later Billman was discharged with pain medication and referred to a pain management clinic.
She attended an outpatient's clinic at the hospital on May 3 where she told a registrar there had been no improvement in her condition.
During a phone consultation with a pain specialist on June 8 Billman declined an epidural steroid injection because she was worried about risks and was told relief would only last a month.
In September Billman was assessed again and claims she was recommended for the spinal operation.
"He said I would have 70 to 80 per cent improvement. Not that I'm really looking forward to spinal surgery but it would make my life a lot better."
Billman said daily life was difficult because of the pain in her lower back, right leg and hips, and numbness and heaviness of her leg.
"I was an active 72-year-old. Now I can't stand for long. I have to crawl out of bed. I have to sit there until I can stand up and it has deteriorated since I saw the surgeon."
The grandmother can't do all the things she used to love including walking the dog, cooking, baking and gardening.
She uses a cane to walk while her husband, who still works, must keep up the housework because they don't qualify for home help.
Billman said the couple have investigated the cost of a stair lift and may even have to sell their two-storey house.
She said she was told by the orthopaedic surgeon she would have to go on the elective surgery waiting list for four to five months, which the couple accepted.
But a few weeks later on October 18, Billman received a letter from Waikato District Health Board stating that because she was less severely affected than many other patients requiring surgery she would not be added to the waiting list.
"Public hospitals have a set amount of funding for assessing and treating patients, and as a matter of fairness, we are obliged to endeavour to see those people with the greatest need first," the letter said.
Waikato DHB executive director of Waikato Hospital service Brett Paradine said Billman did not meet the threshold for spinal surgery based on pain, mobility, assistance needed, consequences of delay and what benefit would be gained.
He said Billman was assessed as scoring 45, below the national threshold.
The DHB said Billman was never scheduled for elective surgery and was only a "possibility" of surgery when she was admitted to hospital in March.
It was decided non-operative management was better.
A DHB spokeswoman said the hospital did not recommend Billman for surgery in September.