By Daily Mail Reporter UPDATED: 18:23 EST, 27 January 2012 A tubby tom cat has become the country's first ever feline to undergo knee-replacement surgery after vets ruled out amputating his cancer-stricken leg because of his size. Cyrano, a 10-year-old kitty who weighs more than 20 pounds, has been helped by doctors and engineers at North Carolina State University after cancer left his left hind leg almost useless. Surgeon Denis Marcellin-Little and  university engineer Ola Harryssonare are at the forefront of osseointegration, a process in which a prosthetic limb is fused to a living bone. Sitting kitty: Cyrano awaits the operation to replace his knee that was weakened by cancer. He is joined by (left to right) engineer Ola Harrysson, surgeon Denis Marcellin-Little and handler Crystal Ritenour
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Cyrano underwent surgery after cancer left his leg weak and useless - but his body was too heavy to have it amputated
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Surgeons used materials similar to those used in human knee operations
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