A year ago, pig Willow could barely move. When the three-year-old rescue animal was brought to the Cornell University Nemo Farm Animal Hospital at the College of Veterinary Medicine in January, severe lameness in several limbs prevented her from even lifting herself off the ground. Today she is walking again – thanks to the first known elbow replacement in a pet pig and intensive care by her team of Cornell veterinarians and loving owners.

“It was really hard, but Willow’s very happy now that she is standing up on all fours again,” said Emily Mueller, who single-handedly takes care of a dozen pigs at the Where Pigs Fly Rescue and Sanctuary in East Haddam, Connecticut. She saves all her animals from severe neglect or abuse and offers them cushy stalls with big piles of straw to recuperate until she finds them new homes. Willow had been used for breeding (she is a Kunekune, a type of domestic pig from New Zealand) and came to Mueller through her friend and fellow animal rescuer Todd Friedman of Arthur’s Acres Animal Sanctuary in Parksville, New York. “Willow couldn’t even get up to go to the bathroom,” Mueller recounted. “It was so pitiful. I didn’t know if it was kinder to euthanize her or try to help her.” Friedman convinced her to give Cornell a try. “I’m so glad I made that decision for her,” Mueller said.

A pig with problems

Willow’s list of issues was long. Lameness in her hindlimbs was due to patellar luxation – her kneecaps were not gliding properly – and a CT scan revealed that the pig had severe arthritis in her left elbow joint. “This is a common affliction in pigs, and it is challenging to manage medically by oral medications or joint injections,” said Dr. Rebecca McOnie, instructor in the Department of Clinical Sciences’ section of large animal surgery and the managing clinician for this case. On top of her orthopedic diseases, Willow suffered from entropion – her eyelids rolling inwards, causing her lashes to rub against her cornea.

Soon after Willow’s arrival, McOnie began to assemble a team and a long-term plan to tackle the pig’s issues. To begin, Rory Todhunter, Ph.D. ’92, the Maurice R. and Corinne P. Greenberg Professor of Surgery, and Michelle Delco ’98, D.V.M. ’02, Ph.D. ’16, the Harry M. Zweig Assistant Research Professor – both in the Department of Clinical Sciences – operated on the pig’s right hindlimb to improve her comfort and start her road to recovery. Under the same anesthesia, an ophthalmology team performed a Hotz-Celsus procedure, removing a small section of lower eyelid skin to prevent corneal injury.

After three months of pain management, rehabilitation and weight loss at the hospital, she was ready for the next big procedure. McOnie’s assembled team decided to replace her arthritic elbow, rather than amputating the limb or fusing the joint, which would have fixed it at a specific angle. “We elected to replace all of the bone and cartilage of the joint surfaces of the elbow, since this is where the pain in her elbow was coming from,” said Selena Tinga, D.V.M. ’12, assistant professor in the section of small animal surgery in the Department of Clinical Sciences. “A successful elbow joint replacement would alleviate her pain while maintaining joint motion.”

A rare procedure

Tinga and Dr. Santiago Mejia (then a resident at the animal hospital, and now a surgeon with the Cornell Ruffian Equine Specialists) as well as the hospital’s operating room team, anesthesia and imaging teams were joined by Dr. Laurent Guiot, a small animal surgeon with specializations in orthopedic trauma and minimally invasive orthopedic surgery, who flew in from Los Angeles, California to assist with the procedure. With the help of a 3D-printed reconstruction of Willow’s limb, Guiot determined that a commercially available canine elbow was compatible with the pig’s anatomy. “Dr. Guiot is an experienced canine elbow replacement surgeon,” said McOnie. “Although we perform many orthopedic procedures on pigs, it was important to have a lead surgeon who was very comfortable with navigating the specific challenges and equipment required for joint surgery.” Guiot’s visit also allowed the Cornell teams to learn new and specific techniques from the rare procedure and paved the way for future elbow replacements in companion animal patients at Cornell. The 3D-printed limb was provided by Med Dimensions, a start-up company founded by third-year veterinary student Sean Bellefeuille, D.V.M.'24.

Different from canine joint replacements, the pig’s bulkier musculature required the team to approach the elbow from an outside rather than an inside angle. The surgeons then used specially 3D-printed instruments to accurately place the prosthetic and confirmed its correct location with post-operative x-rays. “Willow's elbow replacement went very well as a result of outstanding planning and effort by numerous clinicians, staff and students,” McOnie said.

Dedication to success

While interest in porcine joint replacements may grow as elbow arthritis becomes increasingly recognized as a source of discomfort for pet pigs, McOnie pointed out that the procedure entails a significant financial investment, has potential complications including implant failure or infection, and is labor-intensive for owners, since the patient requires post-operative monitoring, recheck evaluation by a veterinarian, and physiotherapy. “Willow is very lucky to have the owner she has,” Tinga said, noting how Willow’s caretakers have been exemplary in their dedication to covering the significant costs of care and to fostering her recovery.

Today, Willow’s mobility is not perfect, but she is much more comfortable than before. She has taken up residence with Friedman at Arthur’s Acres, closer to the animal hospital, where she goes for continued care. “I’ve been out to visit her,” Mueller said. “She looks fabulous. After how sad and beaten down she was before, she’s bonded with pigs there and is extremely self-assured, walking around like she’s the mayor. She’s in a really good spot.”

Written by Olivia Hall

Video by Darcy Rose Video