What is Osteoarthritis?
Osteoarthritis (OA), or degenerative joint disease (DJD) as it is also known, is a very common condition with 30-50% of animals being affected during their lifetime. Sadly it is also one of the most untreated problems, particularly in the feline population, as it can unfortunately be considered a fact of life when pets slow down as they begin to get older. Unfortunately once the OA cycle has begun there is very little that can be to reverse the process and the focus moves to managing the condition in best possible ways.
To understand better how physiotherapy can help manage this condition, it is important to firstly understand the disease process involved. OA is a chronic and progressive disease that is characterised by:
- The wearing out of hyaline cartilage, which is a type of cartilage covering the ends of bones where joints are formed.
- Changes in the synovial fluid and membrane. Synovial fluid is a viscous fluid, which is thick and tacky. It provides lubrication of the joint itself and nutrition to the hyaline cartilage.
- Hypertrophy of bone and bone spurs at the joint margins. Bones become enlarged at the ends and the growth of spurs increases stiffness.
Because there is no direct blood supply into the joints, synovial fluid has an important role to play. It nourishes the cartilage during normal weight bearing, when there is mild compression of the cartilage, allowing it to expel and absorb the fluid like a sponge. Inflammation around the joint affects the quality of the synovial fluid, and it becomes less viscous and nutritious making it less able to do its required job. As animals age there is also a natural decrease in the viscosity of the synovial fluid.
The function of the hyaline cartilage is to provide a smooth surface for joint movement and to protect bones against repetitive forces which occur during locomotion. Degradation of this cartilage, impacted by poor nutrition by the synovial fluid, leads to exposure of the underlying bone surfaces which then begin to wear abnormally.
The response by the body to try and prevent against further damage and pain unfortunately has little beneficial effect. Symptoms such as joint swelling, periarticular osteophytes (extra bone growth around the joint margins) and fibrosis occur and contribute to stiffness and pain.
Pain ⇒ Decreased Function
Weakness ⇐ Muscle Atrophy
Severe pain and increased stiffness result in a reluctance to exercise, which further leads to loss of muscular support and strength. Quality of life is reduced and for some animals the chronic disability can lead to depression.
Causes of Osteoarthritis
Causes can be classified as primary or secondary.
Primary causes include:
- Genetic predisposition
- Gender – females are at higher risk
Secondary Causes include:
- Joint immobilisation
- Mechanical injury or joint trauma (including joint surgery)
- Congenital & developmental abnormalities (such as hip/elbow dysplasia 0r OCD)
- Infectious processes
- Joint instability
As the title suggests, Primary causes cannot be influenced or changed. With secondary causes the OA cycle is triggered by an initial disease, condition or event. When these events occur it is important to consider protection of the joints in an attempt to delay the onset of OA for as long as possible.
Know the Symptoms
These lists are by no means exhaustive but give an indication of what to look for. Identifying the symptoms of discomfort are essential to recognising, and treating, this condition as early as possible.
- Stiffness after rest or when getting up ( usually improves with mild activity)
- Altered posture
- Problems going up / down stairs
- Reluctance to jump or get in/out of car
- Changes in mood
- Not getting up to greet visitors
- Not enjoying being groomed / stroked
- Reluctance or difficulty in jumping
- Not enjoying being stroked/groomed. Decrease in self grooming
- Changes in mood
- Difficulty getting in / out of litter tray
- Toileting outside of litter tray
- Decreased activity
What can be Done?
- Pain Medications
Good pain control is essential and should be the first port of call. In the initial stages pain is acute and should be treated appropriately. Acute pain has a biological purpose in limiting activity and protecting against further damage. This said, it should still not be ignored.
If allowed to progress, or without adequate control, pain can become a chronic problem. Chronic pain can be much more difficult to deal with due to a phenomenon known as ‘wind-up’. When this happens nerve fibres, which transmit nerve signals from the body to the brain, become over -stimulated and repeatedly send out signals indicating that pain has been perceived. With increased duration these nerve fibres become increasingly efficient at firing, and also with increasing intensity. In addition to this the brains sensitivity to these signals increases, making pain seem much worse, even though the actual pain stimulus may not have changed.
Always see your vet if you think pain control may be required or if it is not adequate. There are many different pain medications available, which aim to block pain signals at different sites in the body, and some cases may require a combination to achieve sufficient control.
Staying active is a critical component of OA management and physiotherapy is great way of doing targeted exercises in a controlled manner. When animals experience pain and inflammation one of the first responses is lameness, and this reduces the weight put through the limb. Over a prolonged period this causes loss of muscle and weakness, increased stiffness and pain as well as secondary effects on other areas of the body.
Losing muscle mass may not seem so important when you consider that older dogs generally do less vigorous exercise naturally. However, muscular strength provides a vital support structure for joints. Muscular weakness can contribute to joint instability and further compromise the joint, as well as making functional movements like sitting, getting out of bed or climbing that step into the house more difficult. These become tasks which need careful consideration before attempting, and sometimes it becomes easier to avoid them altogether. Physiotherapy includes many different modalities, often there will be a set ‘exercise prescription’ and owners really enjoy the fact that, despite feeling helpless, there are actually things that they can do at home to help their animals cope with this condition much better.
Massage can help decrease overall pain by working on other areas that have become overused due to the altered weight distribution. Managing the body as a whole, rather than isolating the affected joints can increase comfort levels significantly. Tissues become restricted and instead of soft tissues gliding over each other to allow movement, they become velcro like and begin to ‘stick’ together. Commonly the muscles of the back can become very tight and develop trigger points, or knots, or may even spasm. Likewise the ‘good’ limbs also carry more weight as those affected limb(s) try to lighten the load, leaving them susceptible to muscular soreness. Massage is usually very relaxing for most animals and they quickly learn to enjoy the treatments. There will also be massage techniques owners can carry out at home in between treatments.
Other manual therapies target the joints themselves, these include passive range of motion and joint mobilisations. These techniques aim to increase joint health, reduce stiffness and pain and increase the available range of motion.
Electrotherapies can be used for a variety of purposes and include Pulsed Magnetic Field Therapy and Laser. Therapies are totally painless and many animals are able to relax and enjoy treatments.
Pulsed magnetic field therapy utilises magnetic currents to have a desired effect on tissues at a cellular level. It is applied using pads which can either be placed under the animals bed for particularly nervous animals, or can be in direct contact with the animal. It can be used for a variety of functions, including: additional non-systemic pain relief, reducing inflammation and promoting healing of joint structures as well as vasodilative effects which can improve areas of muscular soreness.
Laser is becoming an increasingly popular modality and uses light therapy to stimulate cells and enhance their function. Laser can also be used for a variety of functions including: pain relief, reducing inflammation, promoting healing and decreasing fibrosis. Laser is also well very well accepted by most patients.
Active exercise is essential and therapists can set exercises for every level of capability. Getting the animal to use the limb correctly has positive impacts on joint nutrition, functional movement, posture and pain levels and should form part of any home program. Exercises do not need to be complicated or difficult, and in fact should be well within the animals capabilities. Do not be mislead however, just because exercises are not physically exhausting does not mean they won’t help. Gentle exercises aim to work the joint and soft tissues without triggering an inflammatory response, so not contributing to the disease cycle. The important thing to note with therapeutic exercises is that they do not put any concussive forces through joints – the strength comes from carrying out exercises in a slow and controlled manner, which is much more difficult than crashing through them at lightening speed. Cats can be surprisingly accepting of exercise programs as well.
The application of heat and cold therapy can be beneficial in easing joint stiffness and reducing inflammation respectively. Both also provide an element of additional pain relief as well. Thermal therapies are easy for owners to apply to home, although advice should always be taken on when to apply each one and the various application times
Kinesiology taping (K-taping) is a relatively new concept in the veterinary physiotherapy field. It utilises therapeutic elastic tape to decrease pain, inflammation and movement dysfunction. K-taping does not restrict movement in any way and works by having a mechanical lifting effect on the skin and connective tissues which underlie it. This means it can also aid the treatment of fascial restrictions and muscle spasms/trigger points. There are also neurological benefits, due to sensory receptors in the skin being stimulated, which can also help patients with OA.
K-tape is well tolerated and usually stays in place for 3-5 days and so provides a continuous mode of action in the days following physiotherapy treatments.
Hydrotherapy is a form of physiotherapy. The buoyancy of the water decreases the weight put through joints during movement whilst hydrostatic pressure can aid in reduction of inflammation. Water also provides a resistance to movement and this resistance can help increase muscular strength as well as improving cardiovascular fitness. Some cats will also tolerate hydrotherapy very well. When looking for a hydrotherapist it is recommended that they are a member of either http://www.canine-hydrotherapy.org/ or http://www.narch.org.uk/Home/Index
There will be many things owners can do at home to make the lives of animals more comfortable. A home physiotherapy appointment will help highlight areas of difficulty and suggest how these may be altered. Hazards in the home include.
Slippery flooring (wood, laminate, some tiles etc) This can a real problem for dogs with joint problems. They contribute to slips and further injury far more than people are prepared to acknowledge. Rugs provide useful ‘safe zones’ and regular routes should be rugged to provide some traction under paw.
Steps. Even if the animal doesn’t go upstairs there may be steps into the house or to get to the garden. The height of steps should be considered in relation to the dogs leg length. Smaller dogs can struggle with steps that we consider small – if the dog has to jump to get up the step then it is too difficult. Where possible make steps suitably shallow and give a bit of distance between each one to provide more stability. Where possible, ramps are the best option.
Bedding. Animals suffering form OA may be inclined to have longer rest periods. Ensure bedding is supportive and large enough from them to stretch out. Memory foam or orthopaedic type beds provide excellent support. Also ensure the sleeping area is away from draughts which may contribute to stiffness.
Feed bowls. Raising the feed bowls decreases the amount of pressure put onto the forelimbs/neck during meal times. Animals normally carry 60% of weight on their forelimbs, due to the weight of the head. When the head lowers to feed from the floor that percentage increases, putting additional stress on the joints which will either be sore (if they are affected) or overused, in the case of hind limb OA.
Most likely the referring vet will have recommended a diet where necessary, and physiotherapy can help weight loss by gently increasing physical exercise. Obesity is a big problem in the pet population and puts unnecessary stress on joints. Because joint surfaces are relatively small in relation to body size the load is amplified four fold, meaning each 1lb of additional body weight puts an additional 4lb of shear force through the joints. Think about that – its massive! Keeping elderly or at risk animals on the lean side can really go a long way to helping joints function better for longer. Dot under estimate the power of weight loss in improving symptoms of OA.
Exercise is important for keeping moving and lead walking may be one of the first active exercises undertaken. Believe it or not, there is a right and wrong way to walk animals with lameness/pain, if the pace is too fast, incorrect gait patterns are more likely to occur. It is essential, however, that it is not overdone. Short frequent walks are much better than one long walk – if the dog comes home lame or has increased stiffness from exercise you have done too much. Too much exercise triggers the inflammatory response within the joint and this contributes to the degenerative process. Short frequent walks are much less likely to trigger an inflammatory response and more likely to be enjoyed. Likewise walks should be consistent between days so avoid the ‘weekend warrior’ scenario where dogs have short walks in the week and then spend the weekend hiking out in the hills. This will be very likely to trigger that inflammatory response and increase pain and stiffness.
Other Elements to Consider
This is a massive topic in itself, and there are many different opinions on elements within the diet that may aid in slowing down the progression of OA. There are a variety of well known brands that offer ‘joint diets’ and so it is best to ask your vet what is appropriate for your individual animal, taking into consideration any other medical conditions that may be present as well.
Also consider calorie intake, if an animal is doing less physical activity than previously, then maintaining the same calorie intake is likely to increase body weight. Low calorie versions are available in many diets, and specific joint diets usually have accounted for this. It is also worth weighing out the daily feeding amount, as stated on the packaging, it can be surprising to see the reality of how little they actually need.
- Joint supplements
Joint supplements is a growing area and can be a subject for debate, with some people liking them whilst others think they have little benefit. Some manufacturers now are conducting there own studies to prove efficacy and so it is best to discuss this with a veterinary professional before buying. There are many different brands of joint supplements available, and many vets have their own preferred option. All of them will contain Glucosamine and Chondroitin, but that does not mean they are all the same. Chondroitin should be of a low molecular weight to ensure sufficient absorption in the body. All the different brands also have other additional ingredients which vary brand to brand. These may include; green lipped mussel (a source of omega 3 fatty acids), ASU’s, circumoids and Bowellia extract. All are said to have anti-inflammatory properties in animals with osteoarthritis.
Supplements are also available for cats.
Acupuncture is a traditional Chinese medicine that can be difficult to get the modern day brain to understand. However it has been around for thousands of years and has research to support its effectiveness. It must be carried out by a trained veterinary surgeon who is suitably qualified in the field. Benefits in OA patients include: reduction of muscle spasms, decreased inflammation and promoting tissue healing whilst also causing the release of endorphins. Veterinary acupuncturists should be registered with the Association of British Acupunturists http://www.abva.co.uk/
On that note it should be said that it is also important to use a qualified and registered veterinary physiotherapist. I am a member of the Institute of Registered Veterinary and Animal Physiotherapists (IRVAP) https://www.irvap.org.uk/ There are also several other registers out there with equally qualified therapists. The industry is working towards a collective register where all therapists who meet the standards can be registered in one place, making it much easier for owners, and indeed vets, to know who is who in the world of animal therapy, but until then it is best to check with individual therapists what their qualifications are.
Osteoarthritis is an area that is subject to a lot of research, and this article mainly focuses on the benefits of physiotherapy. Because of this ongoing research there are also a number of different alternatives, newer and also regenerative medical treatments that may be suggested by your vet. The hope in writing this however, is that owners can see how much more we can do for animals with osteoarthritis, and how physiotherapy has an important role to play. Managing this condition effectively is about so much more than the traditional painkillers and rest!