Southland Hospital staff member Kerren Glasson was given "sole responsibility for the cardiac ultrasound section" in a letter from the SDHB to her in 1996.
She worked as a sonographer, was funded by the Southland Hospital Tertiary Fund to study sonography, and the SDHB supported Ms Glasson's 2012 application to be registered as a cardiac sonographer.
However, the SDHB employed Ms Glasson as a clinical physiologist and paid her accordingly, about $400 a week less than a sonographer would receive.
Two years ago, the Employment Relations Authority ruled Ms Glasson was a sonographer, a decision the SDHB appealed to the Employment Court.
In a recent judgement, the court found in Ms Glasson's favour, and awarded her backpay totalling more than $106,000 from the start of the dispute, further backpay from August 31 last year and costs and disbursements.
Judge Kerry Smith said the DHB was "caught in a contradiction" in considering Ms Glasson was a sonographer when it supported her registration application but then decided she was a clinical physiologist.
"The DHB's justification for its stance, by claiming a need for flexibility gained by Ms Glasson being employed as a clinical physiologist, is also inconsistent with the reality of the situation," Judge Smith said.
"The waiting list for cardiac sonography in Invercargill has been growing, recently extending from about six to eight weeks up to 12 weeks, caused partly by an increase in demand.
"Ms Glasson is as busy as she has ever been performing ultrasound work and the demand seems unlikely to abate."
Ms Glasson's case was supported by two University of Otago academics, who said she was working as a sonographer; the SDHB's witnesses did not have direct knowledge of Ms Glasson's work, Judge Smith said.
"The DHB's case is inconsistent with Ms Glasson's work," he said.
"It relied heavily on the job description, her initial training, and the fact that clinical physiologists can perform ultrasound, to say that her work was not within the sonographers' coverage clause.
"That approach was too narrow because it concentrated on historical events, such as the now nearly 10-year-old position description, and not on the work actually being performed."
Ms Glasson first asked the SDHB to be covered by the sonographer's collective agreement in 2013 and she asked the court to consider her as being a sonographer from that date.
Judge Smith agreed, and said to choose a later date would effectively reward the SDHB for failing to recognise the real nature of Ms Glasson's work.
SDHB people, culture and technology executive Mike Collins said the board would not take the matter further.
"This ruling is the end of the litigation process and we're assessing the impacts of the judgement."
