Canine Joint Disease and Pain Management: Big Barker Interviews Penn Vet's Dr. Kimberly Agnello
Big Barker’s consulting veterinarian, Dr. Sarah Wooten,kicks off her interviewseries with a very special interviewee—Dr.Kimberly Agnello,Assistant Professor of Small Animal Surgery, University of Pennsylvania. We would like to gratefully acknowledge Dr. Agnello’s time and her willingness to share her insights with us!
Dr. Sarah Wooten: Cranial cruciate ligament rupture is the most common knee injury in dogs, but the cause is still unknown. Do you have any thoughts as to the cause? What are the recommended treatments, and is there any way to prevent it from happening?
Dr. Kimberly Agnello: The cause for CCLR is still unknown, but it is likely multifactorial. There are conformational reasons for the ligament tearing. Inflammatory mediators and infectious causes have also been blamed. There is a study that shows a genetic component in Newfoundlands, and a post-mortem study in Labrador Retrievers that shows fibrous changes at the core of the ligament that weakens the ligament. The current thought is that if the ligament tears after ordinary movement, then there is a high likelihood that the disease is going to be bilateral, and nothing, not even preventing the dog from jumping, will prevent it from happening.
The most popular procedure is a TPLO, even for small dogs! There has been some research done into where exactly the dogs feel pain in their knee when the ligament tears. For some dogs, the instability in the joint causes pain, and the TPLO procedure reduces that pain. For other dogs, it is the torn ligament that hurts, and these dogs benefit more from minimally invasive arthroscopy. Still other dogs seem to have patellar femoral pain, and these dogs may benefit from a TTA. In the future, we may develop ways to determine where exactly the dog hurts and recommend the most appropriate treatment that will reduce pain and increase the dog’s quality of life.
My area of interest lies in minimally invasive treatments and studying the other variables in cruciate ligament disease to develop better ways to treat this disease.
SW: If surgery is not an option, what are your top recommendations on how to improve quality of life and reduce chronic pain in a dog with chronic joint disease?
KA: I recommend maintaining a healthy weight and controlling pain with appropriate medication. Once the pain is controlled, then controlled strengthening in the form of rehabilitation exercises is vital to maintaining strength and mobility. Even one visit to a canine rehabilitation veterinarian is beneficial, as clients can easily learn how to put their dog through exercises that will control pain. Clients also ask me about orthotic braces. I have not had much success with braces and don’t recommend them.
SW: If you had a big platform to tell a LOT of dog owners something that would help them care better for their pets and improve their quality of life, what would you say?
KA: Maintaining a healthy weight in your dog is one of the easiest, cheapest, and most important ways that pet owners can reduce pain associated with arthritis. I had a recent hip dysplasia case where the dog initially presented overweight and in pain from hip dysplasia. The dog was scheduled for hip surgery, but first the client was instructed to put the dog on a diet to lose a specified amount of weight. Turns out, the dog lost the weight and improved so much that the dog ended up not needing hip surgery.
SW: What are the most exciting advances in pain management for canines that we should be looking for in the next five years?
KA: To me, the most exciting and promising advances in treatment of arthritis in dogs are translational studies. Arthritic dogs are an almost perfect model for arthritic humans, which means that while researchers are developing new treatments for arthritis in humans, dogs also benefit. In terms of specific treatments, I am most excited about treatments designed to resurface cartilage, partial joint replacements, autologous transplants with cadaver ligaments, and studies to improve the blood supply to cartilage.
SW: What is your advice to general practitioners on how to communicate the importance of pain management to their clients? People still don’t understand that their dog is in pain. Any tips on how to explain it better in a way that the general population will understand?
KA: I tend to explain pain by drawing analogies to orthopedic pain in humans. A sprained ankle is a great analogy—if a dog is limping due to a ligament tear, I tell clients their dog’s pain feels like a badly sprained ankle. I also give clients a trial of pain medication, and then ask them to see if there is any difference in their dog’s behavior at home—how often do they get up, do they go look out the window, do they sleep more soundly, etc. Showing clients what their dog looks like when the pain is managed often works better than telling them.
SW: Are you familiar with Big Barker beds? What do you like about them? What benefits or differences have you seen in your patients?
KA: [Penn Vet’s Ryan Hospital] hasbeen using these beds in our orthopedic wards, neurological service wards, and in the oncology service. When dogs come to the clinic to get cancer treatments, they sit on the hard floor all day and they leave the hospital sore! These older dogs often not only have cancer, they are suffering from arthritis. The biggest benefit I have seen is that these beds help our patients to be comfortable while they are in the hospital because the beds protect their joints. Also, Big Barker beds are easy to clean, which is important because so many different dogs sit on them.
 i.e. knock kneed, bow legged, knee cap luxations, etc.
 Tibial plateau leveling osteotomy, which is a surgical procedure that is intended to stabilize the knee joint
 Patellar femoral pain is analogous to “runner’s pain” in humans and is associated with pain that radiates around the kneecap.
 Tibial tuberosity advancement, a surgical procedure that uses the strength of the patellar tendon to stabilize the knee joint and reduces patellar femoral pain
 i.e., transplanted ligaments from organ donors
Dr. Sarah Wooten is Big Barker’s consulting veterinarian. Dr. Wooten is a small animal veterinarian with more than 15 years of clinical experience. She is an expert contributor to sites such as vetstreet.com, DVM360.com, and The Bark Magazine.