Many pharmacologic approaches are currently available for OA, including nonsteroidal anti-inflammatory drugs, chondroitin sulfate proteoglycans and other analgesics. These drugs unquestionably offer relief. However, alternative and complementary treatments are being increasingly considered for OA. Patients may benefit from these additional treatments because they can help maintain mobility and manage pain. But the truth is, there still is so much we don’t know.
“It would be ridiculous to think that a single treatment would be very effective,” says Dr. Darryl Millis from the University of Tennessee, who is conducting a study on alternative therapies for OA with funding from Morris Animal Foundation. “Rather, a multimodal approach is needed to treat several of these pathways to maximize results.”
For 63 years, Morris Animal Foundation has funded research studies whose merits are evaluated by a distinguished panels of experts. Studies aren’t funded based on their ability to create a marketed product, but are instead evaluated for their technical merits and potential to create a healthier tomorrow for animals. As a result, scientists from all facets of veterinary medicine receive funding to address the most important questions in the field. Increasingly, those questions have revolved around the applicability of integrated approaches to animal care.
With support from our Foundation, Dr. Millis is evaluating three alternative modalities for treating canine OA of the hip or stifle joint:
1. Transcutaneous electrical nerve stimulation (TENS)
2. Low-level laser therapy
He estimates that 20% of adult dogs suffer from the disease, and because some don’t respond to or cannot tolerate drug therapies, complementary care could provide an attractive option. However, one thing missing from the discussion is a solid, apples-to-apples comparison of these modalities in a clinical setting.
At Morris Animal Foundation, we strongly believe that all therapies used to treat diseases of companion animals should be scientifically proven to be beneficial before being widely implemented, and we’re proud to play a role in providing that proof.
This is not to imply we know nothing about these alternative treatments. Several studies of humans with OA have demonstrated benefits for adjunctive pain management with no adverse effects.
• For example, TENS has been used in human medicine to treat chronic OA pain and reportedly works by the gate theory of pain relief (which suggests that nerves can only conduct so much information, and by overwhelming the nerves with electrical currents, pain signals are not transmitted). • Low-level laser therapy is postulated to provide pain relief through endorphin release and alter pain transmission to the brain. • Acupuncture has been used for pain relief associated with OA in dogs and people by activating the endogenous opioid mechanisms in the brain that alter nociceptive processing and pain perception.
Dr. Millis is using objective kinetic evaluation of gait as the primary measures of outcome. Kinematic gait analysis, subjective gait evaluation by a veterinarian, and subjective evaluation of home function by owners are secondary outcome measures.
From a clinical perspective, the TENS unit therapy being evaulated in Dr. Millis’ study seems to be the most effective, but the study will continue through 2012. Co-investigator Dr. Marti Drum reports that owners believe they see an improvement in their pets as a result of some of the treatments we are performing.
“Clearly there is a need to investigate [alternative] treatments for osteoarthritis for our patients,” says Dr. Millis. “Over the years, I have learned you never say never when it comes to a treatment for OA. However, we need objective information from blinded, prospective, placebo-controlled studies to determine whether the treatments are effective.”
Personally, I think this is a great example of the types of studies that need to be performed in order to answer questions about any emerging, empirically derived treatment option. Unfortunately, a combination of factors, ranging from cutbacks in federal and state funding to an increasing scarcity of scientifically trained veterinarians and little incentive for corporations to test competing modalities, has made funding for this type of work very difficult to come by. Morris Animal Foundation has historically filled just such a need.
Ultimately, and despite all that we have learned, there are still so many questions that remain to be answered. Just as we look back to modalities used 200 years ago, so will future veterinarians look back at the treatments we use today and likely smile (or grimace). Only by allowing the hard work of science to proceed will we be able to move the state of veterinary medicine forward to an ever more enlightened age, and bring hope to the millions of animals suffering from diseases like OA.