by E. Mironchik-Frankenberg, DVM.
In the last article, we discussed inflammatory conditions in general and their devastating effects on the body. This month’s topic is inflammation within the musculoskeletal system (bones, joints, and muscles), one of the most commonly affected body systems for this disease process.
There are multiple inflammatory conditions associated with the 3 major components of the musculoskeletal system, and in general terms they are referred to as osteomyelitis (bones), arthritis (joints), and myositis (muscles). Some well-known examples of these in people are fibromyalgia, osteoporosis, and rheumatoid arthritis.
Unfortunately, inflammatory musculoskeletal disorders also affect our pets. In general, these conditions affect the pet’s ability to move. The degree of the impairment depends on the type and severity of the disease. Overall, they can be very painful and life altering, especially when they become chronic. Depending on the specific illness or body part affected, they may result in swelling, lameness, stiffness, muscle wasting, changes in appearance, and fever. Secondary signs often include lack of appetite, lack of energy, weakness, depression, weight loss, other changes in behavior, and poor quality of life.
Let us briefly discuss the three different components in detail…
Muscles: As previously mentioned, myositis refers to an inflammatory reaction in muscle (in contrast to the term myopathy, which refers to a disease that primarily causes damage to the muscles.) Common causes include infections, parasitic diseases, and immune-mediated conditions. It’s important to remember that many different systems in the body rely on the muscles. A pet’s ability to see, breathe, urinate, breed, and even chew and swallow may be affected by a muscular condition.
Some examples in pets are polymyositis and masticatory myositis.
Bones: While less common, these disorders can be quite severe. Osteomyelitis, inflammation of the bone, is most often associated with bacterial infection, although fungal diseases may also be the culprit. In some cases, long term therapy is required and can be extremely frustrating. Factors contributing to the infection include an inadequate blood supply to the bone, trauma, bone damage, and the spread of an infectious agent through the bloodstream.
Examples in pets include panosteitis and various causes of infectious osteomyelitis, such as “Valley Fever.”
Joints: This component of the musculoskeletal system is most commonly affected in our pets. While diseases of bone and muscle can be serious and extremely damaging, joint conditions are seen every day in veterinary clinics. Some of these diseases affect the joint membranes themselves, while other conditions affect the tendons, cartilage, bursae, and fluid within the joint. These disorders may be congenital (present at birth) or may be the result of injury, chronic degeneration (deterioration with loss of function), abnormal development, immune-related conditions, cancers, or infections.
Many examples in pets exist and include the various types of dysplasia (i.e. hip), Legg-Calve-Perthe’s disease, and the different forms of arthritis.
For conditions in this large category, diagnosis relies on imaging, and in some cases, can require multiple testing procedures. Treatments can include a vast range of modalities from benign neglect (aka “watching it”) to extensive surgery and even amputation. Veterinarians typically use multiple forms of therapy including: diet changes, weight loss, strict rest, cold therapy, physical therapy, acupuncture, various surgical treatments, and wide variety of pharmaceuticals (corticosteroids, muscle relaxers, opioids, NSAIDs, immunosuppressants, vitamin supplements, etc.) all aimed to decrease pain, increase function and improve overall quality of life.
By far, the most common of all these conditions in pets is osteoarthritis.
Osteoarthritis, aka degenerative joint disease, is one of the most commonly reported ailments facing pets. According to the American Animal Hospital Association, 20% of dogs and between 40-90% of cats will be affected. These percentages increase with age and other factors such as: previous injuries or surgeries, congenital abnormalities, large breeds (dogs), and weight issues.
Traditional drug treatment for osteoarthritis in pets consists of several classes of prescription medications, all with long lists of side effects. The category veterinarians will usually reach for first are the NSAIDs (non-steroidal anti-inflammatory drugs). We’ve all encountered drugs in this category that includes aspirin, ibuprofen, carprofen, and meloxicam, just to name a few. Even though people and pets utilize these products regularly, long term use increases the risks of vomiting and diarrhea, gastric bleeding and ulceration, and liver/kidney damage in dogs. In cats, this category of drugs can only be used short term due to the risk of dangerous side effects.
Is there any clinical evidence for cannabis use in these conditions?
As noted in the previous article, cannabis can help this type of inflammation via multiple mechanisms in the body. This is one of the few topics in veterinary medicine for which there is a slowly increasing body of evidence to support the use of cannabinoids. The first scientific study on dogs, completed in the U.S. in conjunction with a major veterinary university, was published in 2018. The results were encouraging and indicated that the cannabinoid based product used in the study was well tolerated and effective for dogs with osteoarthritis pain. Since then, more study results have been completed and currently, there are numerous other studies underway to further examine the use of cannabinoids for painful pets.
Pet parents are seeking better, progressive options in getting relief for their furry children. It is reasonable to argue that when treating osteoarthritis, or any musculoskeletal condition characterized by inflammation, reaching for a potent anti-inflammatory compound with a more favorable safety profile than traditional drugs is warranted. Cannabis fits this criteria and may be a valuable addition to the tools needed to manage your pet’s musculoskeletal pain. In addition, it can provide relief for many of the secondary symptoms involved and may even be helpful in decreasing the doses of other prescription medications.
Coming up next: Inflammation part 3: Gastrointestinal inflammatory disorders
References:
5. https://www.aaha.org/globalassets/05-pet-health-resources/mobilitymatters.pdf
7. Pharmacokinetics, Safety and Clinical Efficacy of Cannabidiol Treatment in Osteoarthritic Dogs. Gamble, Boesch, etc. al. Frontiers in Veterinary Science, July 2018; Vol 5, article 165. https://www.frontiersin.org/articles/10.3389/fvets.2018.00165/full
8. The Use of Cannabidiol-Rich Hemp Oil Extract to Treat Canine Osteoarthritis-Related Pain: A Pilot Study. https://www.ahvma.org/wp-content/uploads/Use-of-Cannabidiol-Rich-Hemp-Oil-Sample-Article.pdf
9. https://www.ahvma.org/wp-content/uploads/AHVMA-2018-V52-CannabisAdverseEffects.pdf
