To brace, or not to brace? A commentary on options for treating cranial cruciate ligament disease

To brace, or not to brace? (Getty Images)In a recent Journal Scan, I summarized the results of a survey designed to compare client satisfaction with using orthotic devices to treat cranial cruciate ligament disease (CCLD) in dogs vs. tibial plateau leveling osteotomy (TPLO).

The survey results, published in the August 15, 2016, issue of JAVMA, revealed that the dog owners in the TPLO group had statistically significant higher satisfaction ratings (98% said the treatment outcome was “excellent,” “very good” or “good” vs. 86% in the orthotics group). In addition, 98% of TPLO respondents reported mild or no lameness in their dogs vs. 88% of respondents in the orthosis group, also a statistically significant difference. And while only 5% of the TPLO respondents reported complications from the surgery, 46% of orthotics respondents reported skin problems.1 Based on the survey results and the authors' conclusions, I suggested that veterinarians could consider orthotics when surgery is not an option but to be aware of potential issues and communicate them to the owners.

Upon reading the Journal Scan, David Dycus, DVM, MS, CCRP, DACVS-SA, felt there was more to be said about client information needs regarding orthotic devices. Because owners often have preconceived notions about orthopedic devices from their own experiences, Dr. Dycus comments that it's the veterinarian's job to highlight the differences and possible complications so clients know what to expect and can make informed decisions. And because the survey also revealed that a veterinarian's recommendation is one of the deciding factors clients use when choosing between orthotics and surgery, it's important that veterinarians stay up to date on orthotics research and development. 

Here are the four key topics Dr. Dycus covers with clients considering orthotic devices:

1. Tolerability

We can't ask dogs how they feel about wearing a device, nor can we predict whether or not they will get used to it over time, Dr. Dycus says. For a stifle orthotic to work well, the dog has to be comfortable in it and like wearing it. Otherwise, he explains, the dog will change its gait and the orthotic is no longer beneficial.

According to the survey results, 7% of dogs “never tolerated the orthosis because of fit issues or skin problems.”1 Nineteen percent only tolerated it fair (meaning the dogs tolerated the device but were reluctant to both put it on and wear it),1 which, according to Dr. Dycus, negates the benefits of orthosis. And while the orthotic devices were custom-made to fit each dog, 46% of the dogs in the orthosis group developed skin problems while wearing the device-32% of which required medical attention.1

Considering the fact that these custom-made devices must be invested in before learning how well they're tolerated, a client could spend more than $500-1,000 for a device their dog can't (or won't) use.2 Dr. Dycus recommends that clients factor this risk into their decision.

Furthermore, veterinarians should alert clients to the likelihood of future costs, because if the pet tolerates the orthotic device well, the device may become worn and may need to be replaced during the pet's lifetime.

2. Osteoarthritis

Dr. Dycus reminds us that one of the main goals in treating CCLD is to slow down and minimize osteoarthritis (OA) development. Although it is thought that TPLO surgery can minimize and slow the progression of OA, the effect of orthosis on OA remains unknown. 

When talking to clients, Dr. Dycus uses a spectrum to illustrate. At one end of the spectrum is to do nothing. “At that end, we expect osteoarthritic changes to progress more rapidly,” he says. TPLO surgery is at the opposite end of the spectrum, where, according to Dr. Dycus, osteoarthritic changes are expected to progress more slowly. “Orthotic devices fall somewhere along this spectrum,” he explains, “but we aren't sure where at this point. More research is needed to know if it's as good as doing surgery, as bad as doing nothing or somewhere in-between.”

3. Meniscal injury

Dr. Dycus calls the meniscus the “forgotten child” of CCLD. “With an unstable stifle, there is a high likelihood of the meniscus becoming torn,” he explains. In Dr. Dycus' experience, dogs that present with concurrent CCLD and meniscal injury tend to do poorly in a brace. The reason for this is that in theory, a stifle orthotic will minimize cranial subluxation of the tibia in relation to the femur. However, it will do nothing to minimize the concussive forces between the tibia and the femur when bearing weight.

Again, Dr. Dycus likes to use a spectrum to illustrate. At one end of the spectrum is to do nothing, “where we expect a high probability of meniscal injury development,” he explains. At the other end of the spectrum is TPLO surgery, where, according to Dr. Dycus, the odds of developing a postoperative meniscal tear are minimal. Orthotic devices fall somewhere along this spectrum, but their exact location is still unknown. “Will it prevent meniscal injury as well as doing surgery?” Dr. Dycus asks. “Or will the meniscal tear rate be the same as doing nothing? More research is needed.”

The matter is further complicated by how difficult it is to diagnose a meniscal tear, Dr. Dycus explains. MRIs require general anesthesia and are costly without offering guarantees of meniscal tear detection. Stifle arthroscopy would allow direct observation, but it is also expensive and requires general anesthesia. And because it is a surgical procedure, it would make the most sense to go ahead and stabilize the stifle at the time of the arthroscopy.

Alternatively, Dr. Dycus recommends using diagnostic musculoskeletal ultrasound. This is a minimally invasive (no sedation or anesthesia required) way to try and evaluate the meniscus. If there is evidence of a meniscal tear via the ultrasound, Dr. Dycus advises against the use of orthotic devices. If there is no evidence of a meniscal injury, however, he offers orthosis as an option but explains that the true sensitivity and specificity of meniscal injuries documented by ultrasound is currently unknown. 

4. Expectations regarding return on investment

Dogs treated with orthosis are not expected to return to their pre-injury activity level (as is expected with surgical fixation). While a recent study showed that dogs fitted with orthotic devices demonstrated improved weight bearing, weight bearing in the affected limb decreased as soon as the orthotic was removed.3 Dogs fitted with orthotic devices will likely need to wear them for life. Moreover, patients will continue to compensate to the contralateral side in an orthotic,3 which may increase the chances of a contralateral tear.

Conclusion: More research and communication

Because orthosis is relatively new and uncharted (studies to date have examined braces from only two companies), Dr. Dycus thinks we need more research on its effects on the stifle joint in patients with CCLD as well as more defined patient selection criteria. Patients wearing devices also need to be followed for longer periods to assess long-term results.

Orthotic devices may be an exciting new option to manage CCLD, but there remains a need for thorough communication to clients. Explaining all of the pros and cons, as well as the misconceptions, about orthotics to clients helps manage their expectations and can be critical to their satisfaction with their pets' treatment.

References

Hart JL, May KD, Kieves NR, et al. Comparison of owner satisfaction between stifle joint orthoses and tibial plateau leveling osteotomy for the management of cranial cruciate ligament disease in dogs. J Am Vet Med Assoc 2016;249(4):391-398.

Carr BJ, Dycus DL. Canine Orthotic Devices. Today's Veterinary Practice 2016;6(1):117-125. 

Carr BJ, Canapp Jr. SO, Meilleur S, et al. The use of canine stifle orthotics for cranial cruciate ligament insufficiency. Veterinary Evidence Online 2016;1(1).

Kathryn Primm, DVM, owns and practices at Applebrook Animal Hospital in Ooltewah, Tennessee, and is the author of Tennessee Tails: Pets and Their People.