A Canberra woman injured when an office chair collapsed under her has had her compensation raised to more than $1.1 million in a private court case.

Terry Anne Downie had been working as a team leader at the Community Information Referral Service ACT in June 2002 when she purchased furniture from Ex-Government Furniture, Fyshwick, including a chair for her own use.

In October, Ms Downie was on the telephone when two legs of her chair snapped and she fell to the floor. She was unable to rise and felt a sharp pain on the left side of her lower back.

A co-worker who saw the incident said she heard a loud crack, and turned to find Ms Downie had been flung into a corner and was lying in an awkward position.

Treatment failed to fix the injury and scans revealed a bulging disc was in contact with a nerve root.

Doctors told the court Ms Downie probably had asymptomatic degeneration in the lower spine consistent with her age before the injury.

The court heard she had been fit and active, including finishing third in a triathlon in Perth, before the accident.

Ms Downie, now 51, said the mishap had caused her continuing pain, employment problems, mental illness, sexual dysfunction, and the sensation of ants crawling under the skin of her legs.

She was paid $190,000 in workers' compensation in 2005. She then took civil action against the chair's manufacturer, Jantom, claiming negligence. Her employer claimed against the manufacturer for the amount paid in workers' compensation, arguing negligence and indemnity.

Master David Harper, in a judgment handed down in the ACT Supreme Court this week, ordered Jantom and its insurer, GIO, to pay Ms Downie $933,030.

He also entered judgment for the Community Information Referral Service ACT against the same defendants for the sum of $441,911.90.

"I accept that she has been left with permanent and often severe low back pain, and permanent sciatica down the left leg," Master Harper wrote. "I accept that the pain is debilitating and has caused a substantial interference with the plaintiff's working life, home life and personal relationships.

"She continues to suffer from depression and anxiety, and there is apparently not much room for optimism that she will ever recover from her psychological condition, although some further improvement may be expected over time."

Master Harper said the accident had altered her life and would continue to do so.

"She has many years ahead of pain and depression. Her life is very different to the life she could have expected if it had not been for her injury. Her enjoyment of life, and the kind of life she is able to lead, have been altered immeasurably."