Britain’s biggest dog – Samson, a Great Dane-Newfoundland mix who stands 6 feet 6 inches tall on his hind legs – needs life-saving surgery to his leg.

Samson has a ruptured cruciate ligament, and without the $2,800 surgery may have to be put down.

“Samson is in crisis,” says owner Julie Woods in an interview with the U.K.’s Daily Mail. “Without the surgery it could end up being euthanasia. It really is quite desperate. We are very upset, we love him to bits. At the moment Samson is on painkillers and has been told to rest, but you try stopping a 273-pound dog from tearing around.”

Woods and her husband rescued Samson from an animal shelter when he was six months old, and say they cannot afford the fee. British animal charity PDSA has helped pay for Samson’s vet bills to date, but the organization says it can’t pay for surgery.

Woods and her husband have turned to the public for help, launching a fundraising drive called “SOS: Save our Samson.”

“PDSA have been brilliant because it has so far cost quite a lot of money, but unfortunately they can’t pay for such expensive surgery,” Woods says. “We are just appealing to anybody who can help.”