Oscar the cat has a second chance. After an accident with a combine harvester severed his rear paws last October, the cat was at the mercy of his local Channel Islands veterinarian. The vet referred Oscar’s owners to neuro-orthopedic surgeon Noel Fitzpatrick, based in Surrey, UK, who gave the 2-year-old cat new paws in a first-ever surgery.
The foot design uses custom-made implants to “peg” the ankle to the foot and mimics the way that deer antler bone grows through skin. In a three-hour operation, the veterinary surgical team inserted the pegs by drilling into one of the ankle bones in each of the back legs. This delicate feat could have fractured the ankle joint before the procedure began and, even more challengingly, had to be performed twice.
The artificial implants, attached to the bone at an amputation site, are coated with hydroxyapatite, which encourages bone cells to grow onto the metal. The skin grows over the special umbrella at the end of the peg to form a seal against bacteria and infection. The peg itself protrudes through the bone and skin, where the surgeon securely attached the custom-built artificial paws.
After the successful surgery in November, the veterinary team focused on the slow process of rehabilitation and helping Oscar to learn to walk again. This began with using external scaffolding anchored to the tibia for five weeks to protect the new implants until the pegs integrated into the bone and the skin grew onto the peg.
Remarkably, Oscar tred to stand within a day of the operation and, despite overcoming problems with infection, in less than four months Oscar could stand and bear weight equally on all four limbs. He has since been fitted with a series of prototype new paws to ensure the best possible long-term fit and now can claim to a be a truly bionic cat.
The pegs, or ITAPs (intraosseous transcutaneous amputation prosthetics), were first developed by a team from University College London led by Professor Gordon Blunn, Head of the Centre for Bio-Medical Engineering at UCL’s Institute of Orthopaedics and Musculoskeletal Science. Working in partnership with UCL, Fitzpatrick has pioneered the use of these weight-bearing prosthetic implants, combining engineering mechanics with biology to give Oscar the cat two new feet.
The work of this vet is the focus of a new six part documentary series The Bionic Vet, to be broadcast on BBC1 beginning June 30.