One Pro’s Take On Orthopedic Advances
The area under the patella displays the arthritis that occurs from a torn ACL.
TJ Dunn, DVM
Prosthetic limbs on dogs, total knee and elbow replacements, and stem cell therapy are all on the horizon for veterinary orthopedics, according to a veteran Oklahoma State University orthopedic surgeon whose bonafides include more than 270 scientific presentations and 110 publications.
At the same time, Mark Rochat, DVM, MS and diplomate of the American College of Veterinary Surgeons, encourages both practitioners and the lay public to temper the hot prospects of medical breakthroughs with the cool logic of scientific integrity.
Improved prosthetic limbs for people are a by-product of America’s wars in Iraq and Afghanistan, Dr. Rochat said.
“Endoprosthetic that have a stem that can grow into the end of the bone allow for better attachement of the prosthetic to the limb than a sleeve approach,” he said. “Who knows, someday we may routinely be putting limbs on animals. It’s come a long way.
“Now, we have a total knee replacement and several options for total elbow replacement,” added Rochat, a member of the Veterinary Orthopedic Society and small animal surgery professor at OSU’s Center for Veterinary Health Sciences. “Coronoid disease is the most common of the elbow maladies in dogs, and the least understood. No one knows absolutely the best way to treat dogs with coronoid disease.”
As veterinary orthopedics advance, Rochat said elbow replacements may gain popularity as a treatment for advanced osteoarthritis or coronoid disease.
“Hopefully we’ll get better at stratifying coronoid disease and knowing when to do what specific treatment,” he said. “For instance, joint changes in one dog might call for a scope and debridement, whereas another dog’s changes would call for a unicompartmental elbow replacement, while another case with different changes would need a total elbow replacement.”
While stem cell therapy is highly touted, it is “equally highly unproven,” Rochat said. Simply put, this expensive and somewhat invasive process involves harvesting fat from the patient, processing it and then injecting the final product into the joint, he said.
“The intent seems to be reduction of inflammatory mediators, but the effect is short-lived—a matter of months—and is, in my mind, of questionable effectiveness, especially in light of the logistics and costs of the procedure,” Rochat said. “Stem cells injected into tendons for chronic tendon injury are also still far from proven to make any real difference.”
Platelet-rich plasma therapy, another treatment modality, may offer better results, Rochat said.
“The use of PRP therapy seems to be on the rise in human and veterinary medicine, and may have more basis in scientific fact,” he said. “Again, the intent seems to be in providing supra-physiologic levels of anti-inflammatory mediators and reparative mediators to enhance tendon healing. Time will tell if this is really true.”
Rochat said platelet-rich plasma is created by drawing the patient’s blood, processing it either with in-house equipment or sending it out to a lab, then injecting the plasma into the tendon with ultrasound guidance.
While anecdotal observation and limited objective information support both stem cell therapy and PRP, their true effectiveness and how best to use them clinically remains to be determined, he said.
Rochat cited tibial plateau leveling osteotomy and tibial tuberosity advancement surgeries as newer approaches to cranial cruciate ligament disease in dogs, explaining they are aimed at changing the joint mechanics to eliminate tibial thrust and stabilize the stifle during weight-bearing.
“When I came to OSU 19 years ago, TPLO surgery for cruciate disease was just starting to be talked about. Cruciate repair was mostly done by lateral suture, essentially mimicking the action of the anterior cruciate ligament,” Rochat recalled. “Cruciate repair surgery is now largely TPLOs. Another procedure, tibial tuberosity advancement, is a new alternative that is purported to be easier to do, with fewer complications, yet the evolving literature doesn’t totally support that.
“Nevertheless, while the general subjective experience is that TPLO works very well, what little objective science there is still leaves us questioning that,” Rochat continued. “Properly done, a lateral suture stabilization technique can yield good results. Again, the quest for accurate, unbiased evidence for the best solution for cranial cruciate ligament disease continues.”
Laser Disc Ablation
As for spinal surgery, percutaneous laser disc ablation is slowly catching on, he said. The procedure uses laser energy to denature intervertebral disc material to keep it from herniating in the future and causing spinal cord injury.
“But our armamentarium of instrumentation for spinal trauma and fusion is still lacking,” he said. “An artificial disc has now been developed for dogs, so in the future we may be doing that instead of fusion for some diseases.”
Meanwhile, orthopedic practitioners are using more rehabilitation and non-surgical treatments.
“For a long time, we just did surgery and that was the end of it. With a lot of joint conditions, you can make it better but you can’t resolve it or cure it,” Rochat continued. “Rehab is being used more and more as a way to fine-tune what we’re able to do surgically. Rehab is also finding a niche as the preferred way to treat certain musculotendinous conditions that we previously treated only surgically.”
Examples are therapeutic ultrasound, low-intensity laser therapy, physical therapy in general, electrical stimulation and underwater treadmills.
Some therapies can build false hope with unrealistic claims, Rochat said.
“If someone says a treatment basically cures everything, I get skeptical. If they say it’s good for arthritis, cures cancer, aligns the planets and turns the tides—if it’s good for everything, it’s probably good for nothing,” he said. “No single therapy, even the well-established, can offer such broad claims and it’s up to the veterinary practitioner to know how best to employ even valid treatments.
“Our academic ranks are shrinking, and it is more and more of a struggle to properly validate claims,” Rochat continued. “Increasingly, studies that ‘prove’ the effectiveness of a treatment revolve around anecdotal, subjective methods. The problem I see with our profession is that there isn’t the wherewithal to do the critical, well-designed, truly objective studies.”
“Like everything else, marketing of new therapies is financially driven,” he added. “Veterinarians may be excited about the promises of a new treatment or technology but fail to take a deeper look at the science behind it. Sometimes newer or higher-tech may not necessarily be better or may not work at all.”
Rochat said he becomes concerned when people “pour a lot of time and money into chasing the fringe element, when they could be better spent on treatment options that are often less expensive and better scientifically validated.”
“New therapies, whether it’s stem cell, PRP or total joint replacement, aren’t necessarily bad or ineffective, but it’s up to veterinary professionals to use the knowledge they have to vet new technologies and treatments so that they can accurately guide their clients to effective (and cost effective) medical care for their animals,” he said. “As the old adage goes, …. ‘It’s important to keep an open mind but not so open that your brain falls out.’”