The unnamed woman was dropping her seven-year-old daughter off at school in Edinburgh when she was knocked out by the two-metre sign.

She need stitches in a deep cut to her forehead and suffered tissue damage to her left shoulder.

The victim spent two days in hospital and experienced dizziness and speech problems.

She was later diagnosed as having suffered a mild brain injury.

The 43-year-old mature student sued education officials from the City of Edinburgh Council at the city’s sheriff court over the incident at South Morningside Primary School in December 2013.

The sign, which was erected in 2003, was made of plastic and had an aluminium frame.

It was fixed to a plywood board on a wall at the entrance to the school.

The woman told the court she had noticed it flapping in the wind before it blew off.

The court also heard she has a three centimetre scar on her face and is to have psychological counselling.

She won £45,752 in damages after Sheriff Kathrine Mackie ruled the council was at fault as staff had failed to ensure the sign was securely fixed to the wall.

Her written ruling said: “It was, or ought to have been, reasonably foreseeable that the fixings of a sign attached to an external wall would deteriorate, leading to the likelihood that the sign would become unsafe.

“In not assessing the risk of such an event or implementing a regime of inspection which included the sign, the defenders failed to take reasonable care for the safety of visitors to the school.

“If the defenders had inspected the sign fixings at any time prior to the accident, the defects would have been noted and the sign removed or secured. Had that been done the accident would not have occurred.”

Last night, a City of Edinburgh Council spokesman said: “We note the judgment and are considering our response. While we are unable to discuss the details of the particular case, any injury to anyone on council premises is very much regretted.”