Dan O'Connor sits in his living room in Pakenham, Ont., trying to find the words to describe the excruciating pain that racks his body.

He hardly needs to. His agony is plain to see.

Dan O'Connor worked as a paramedic for 24 years before injuring his back while lifting a patient. (Submitted) O'Connor, 54, winces as he shifts his weight in the chair, trying in vain to find a comfortable position. The pain makes it difficult to sit for more than 15 minutes at a time, even with his legs elevated.

When he rises his stooped posture makes him appear much shorter than his frame. When he moves he shuffles rather than walks, reaching for chairs and door frames to steady himself. When sleep comes, it's erratic at best.

O'Connor's condition, caused by a workplace injury three years ago, ended his 19-year career as a paramedic and denied him the satisfaction that came from helping injured people.

Equally devastating, according to O'Connor, have been his dealings with Ontario's Workplace Safety and Insurance Board, which last month cut his benefits in half.

"You're a human being and they don't treat you like a human," he said. "You're almost left begging for assistance."

Injured on the job in 2013

O'Connor joined the Lanark County Paramedic Service in 1994. In August 2013 he suffered a lower back injury while trying to lift a belligerent patient.

I said to the doctor, 'I just can't do this. There's something terribly wrong. It's killing me.' - Dan O'Connor

"I was in shock. It felt like someone took a chainsaw to my abdomen and back and everything in my midsection hurt."

Initial scans showed that in addition to the severe lower back pain he was experiencing, O'Connor had suffered two abdominal hernias, which were corrected with surgery.

When he returned to work O'Connor was given a desk job, but soon discovered the prolonged sitting only intensified his back pain.

An MRI five months after his injury found a herniated disc, two bulging discs, degenerative disc disease and bone spurs in his lower back. It also revealed scoliosis, an abnormal curvature of the spine that had gone undiagnosed.

Pain returned despite therapy, drugs

O'Connor spent most of 2014 off work, attending twice-weekly physiotherapy and occupational therapy sessions at Altum Health, an Ottawa clinic used by WSIB to treat injured workers. Later sessions included psychological counselling.

Dan O'Connor says he can't sit or stand for more than 15 minutes due to pain and spasms in his back. (Laurie Fagan/CBC) The treatments helped for a short time, O'Connor said, but the pain would always come roaring back.

Since his injury O'Connor has been on and off various cocktails of powerful narcotics designed to control his chronic pain. They've included oxycodone, hydromorphone and a fentanyl patch.

Despite the medication, the agony intensified, spreading to the left side of his back, his neck and even his legs.

"My ability to cope with the pain deteriorated," O'Connor said. "I said to the doctor, 'I just can't do this. There's something terribly wrong. It's killing me.' The more I tried to do the worse it got."

O'Connor's situation would get worse still.

Ordered back to work

A January 2015 medical report from Altum declared O'Connor had reached "maximum medical recovery" and could return to work. When he read it, O'Connor broke down.

"To find out you're being bullied into doing something, something you want to do anyway but you're being bullied to do more, that's not the way it should be when someone is injured."

O'Connor reluctantly returned to work on a part-time basis in November 2015. The following spring it was decided he needed computer training to fulfil the demands of his new administrative job, so WSIB enrolled him in a "transitional" program in Ottawa.

The two-hour daily commute and six hours sitting in a classroom proved too much, and in July O'Connor stopped attending the program due to the overwhelming pain.

Denied compensation for 'pre-existing conditions'

An image of Dan O'Connor's back from November 2014 shows scoliosis, an abnormal curvature of the spine. (Submitted) In August O'Connor received a letter from his WSIB case manager informing him that the board would only compensate him for symptoms associated with his two lower vertebrae and not for the pain in his neck and leg, which the board determined to be "pre-existing conditions" and therefore "not compensable."

On a scale of 100 used by the WSIB to evaluate the severity of a client's disability, O'Connor rated just 22.

The letter also characterized O'Connor as a "non-co-operative" client who "complained constantly" to WSIB staff. The board threatened to reduce his benefits if he didn't return to the training program.

That prompted Dr. Terence Woods, an emergency room doctor who treated O'Connor five times at the hospital in Arnprior, to write a letter to the board

Woods believes that despite the board's best intentions to rehabilitate O'Connor, the treatment plan hasn't worked. He considers O'Connor disabled by chronic pain and "simply unable to work."

Injury 'evolved,' doctor believes

Dr. Terence Woods wrote a letter to the WSIB to express his concerns over the handling of Dan O'Connor's case. 'It's an injustice and someone's got to take the time to bring these issues to light.' (Laurie Fagan/CBC News) Woods believes the back pain's migration to other parts of O'Connor's body is an "evolution" of the original injury, and he rejects the notion that it's caused by any pre-existing conditions.

In a follow-up phone conversation with O'Connor's case manager, Woods said his questions were "dodged and deflected," and his medical concerns "ignored."

"If it was [pre-existing], how would you explain him being able to do his job as a paramedic effectively for the last 20 years?" Woods demanded.

"I'm worried his case is driven not by a motivation to return injured workers to work, but to trim the bottom line, because I can't see any other reason for such a dogged persistence to drive this patient along a return to work path that he clearly wasn't tolerating."

Benefits slashed

In September O'Connor's benefits were cut by half, leaving him worried that within a few months he won't be able to pay his mortgage or meet other financial demands.

I can't help feeling that Mr. O'Connor is being almost persecuted, with devastating consequences. - Dr. Terence Woods

"It makes me angry because this has turned my family inside out. My 10-year-old asks what will happen to his bedroom if we lose the house," he said.

"I'm not looking for cash for life. I'm looking for fair treatment. You know you can go to work, do everything by the book, and then get injured and end up where I am."

Woods said he's heard similar stories from other doctors about how some injured workers have been treated.

'It's an injustice'

"It's an injustice and someone's got to take the time to bring these issues to light, and hopefully something will come of it," said Woods.

"I can't help feeling that Mr. O'Connor is being almost persecuted, with devastating consequences."

For privacy reasons, the WSIB can't discuss the cases of individual clients. But John Genise, director of service delivery for the board's Ottawa office, said the policy for dealing with pre-existing conditions changed in 2014 to give case managers more "guidance and rigour" in evaluating workplace injuries.

The situation has left O'Connor, already debilitated by pain, to suffer another kind of torment.

"I failed my family. I'm supposed to provide and keep them safe, and because I got hurt at work that ability has been taken away and I can't do anything about it."