When a Chimpanzee Needed Neurologic Care: How a Veterinary and Human Neurologist Teamed Up to Save Him

When Lu, a 34-year-old chimpanzee at Zoo Knoxville, began dragging his left leg and struggling to climb, his caregivers knew something was wrong. What initially appeared to be a subtle weakness progressed rapidly, and the zoo’s veterinary team referred him to the University of Tennessee College of Veterinary Medicine for advanced neurologic evaluation.

“When Lu arrived, it was clear he had significant weakness in his hind limbs, and we were concerned about a serious spinal cord problem,” explained Board-Certified Veterinary Neurologist, Dr. Talisha Moore. “We completed a neurologic exam and immediately scheduled him for an MRI because primates can deteriorate quickly with spinal cord compression.”

The MRI revealed a rare and challenging diagnosis: a large extradural mass compressing Lu’s spinal cord. The tumor’s location and size made surgery extremely high-risk, and the case even more complex because neurosurgery in chimpanzees is extraordinarily rare.

Recognizing the need for specialized expertise, Dr. Moore partnered with Dr. James A. Killeffer, a human neurosurgeon at the University of Tennessee Medical Center.

“This was the first time I had ever operated on a chimpanzee, but the anatomy of the spine is remarkably similar to humans,” Dr. Killeffer said. “The biggest challenge was adapting our surgical approach to an animal of his size and strength while ensuring safe anesthesia and positioning.”

Together, the veterinary and human neurology teams crafted a detailed plan to remove the tumor and relieve pressure on Lu’s spinal cord. The procedure took place on September 19, 2025, involving dozens of medical professionals.

“Our goal was to give Lu a chance at regaining the ability to move comfortably again. Without surgery, the paralysis would have progressed,” Dr. Moore said.

The surgery was a success. The team carefully accessed the spine, removed the mass, and restored space around the spinal cord. Immediately after the procedure, Lu began to show encouraging signs of improvement.

“Within the first 24 hours, we were already seeing small but meaningful changes in his mobility, which told us the spinal cord was beginning to recover,” Dr. Moore shared.

Recovery for a chimpanzee requires creativity, modified enclosures, 24/7 monitoring, and careful pain management. But Lu handled every challenge with steady progress.

“We expect Lu to keep regaining strength over the next several months. His prognosis is good, and he’s already far more comfortable than before surgery,” said Dr. Killeffer.

Lu’s story is more than a medical milestoneit is a testament to innovation, teamwork, and the shared commitment of human and veterinary medicine. 

Learn more about Lu's case in this episode>>