FROM active 14-year-old to wheelchair-reliant at just 20, Larissa Ralph fights a constant battle against horrific pain, the main symptom of a cruel and debilitating illness.

Beginning one weekend in 2008, a mystery pain in her left leg became so unbearable she spent three weeks in hospital.

A blood clot, spinal injury, stroke and multiple sclerosis were suspects, all subsequently ruled out while Miss Ralph returned to school and tried to lead a normal life between flare-ups of excruciating pain.

She was diagnosed finally with chronic Complex Regional Pain Syndrome (CRPS), which has gradually affected most of her left side, requiring medication including morphine daily to control.

She mainly uses a zimmer frame at home in Greenmeadow, Cwmbran, but trips out require a wheelchair.

If symptoms flare up, often for weeks at a time, the acute discomfort almost paralyses her.

Six years ago Miss Ralph, who lives with mum Tara, dad Colin, and 16-year-old sister Brooklyn, played rugby for the girls' team at Fairwater comprehensive school, ran cross-country, played football, and enjoyed riding her pit bike, a 13th birthday present.

Now, such activity is impossible, as is a career as aircraft cabin crew that she was pursuing.

During one hospital appointment Miss Ralph and her mum were told it was "99.9 per cent certain" she had multiple sclerosis (MS).

"We didn't know what that meant. Larissa asked me if she was dying. I don't know how I drove home," said Mrs Ralph.

After 18 fluctuating months Miss Ralph's condition was revealed as CRPS - believed to affect one in 3,800 people according to one study.

But the condition is poorly understood and often not diagnosed or misdiagnosed.

"It has spread through Larissa's left side and when it flares up it is paralysing. Since January it has affected her left arm, neck, spine, and knee," said Mrs Ralph.

Miss Ralph managed to complete GCSEs and a BTec in travel and tourism, then aimed for an aircraft cabin crew career.

"But recently, she has started collapsing," added Mrs Ralph. "They think something is happening in the back of her brain. But there's no research, doctors don't really know what they're dealing with."

Meanwhile, Miss Ralph has lost touch with many friends, and feels "in limbo" hoping for remission that might not happen, or improvement that might help her mobility.

MISS Ralph is currently under the care of a specialist pain team and a psychologist, and social services have also become involved.

"In the last five months we've been offered more help, and she now has her morphine at home, so she doesn't have to go into hospital for weeks," said Mrs Ralph.

"Social services offered to come in and help, but she doesn't want that at the moment. She's only 20 and it's very hard to accept. She can't shower herself so I have to help her."

Social services have also suggested a downstairs wetroom and bedroom would help, as often she cannot get up or down the stairs. But that will be very expensive and require an extension to the house.

"They are looking into a grant, but we're going to do some fundraising," said Mrs Ralph.

"On Saturday November 1 friends and family will do bag packing in Asda (where Mrs Ralph works part-time), and staff there and at Tesco are to going wear orange to mark national CRPS awareness day on Monday November 3.

"We're planning a cake and coffee morning at the house on the Monday, and looking at doing boot sales and organising discos."