Age affect the structure and function of our pets’ joints and muscles.
Whilst age is not a disease there are physiological changes that occur in our older canine companions which impact the body’s functions. Focusing on the musculoskeletal system there are several changes that occur which affect the structure and function of our pets’ joints and muscles.
Sarcopenia
Whilst age is not a disease there are physiological changes that occur in our older canine companions which impact the body’s functions. Focusing on the musculoskeletal system there are several changes that occur which affect the structure and function of our pets’ joints and muscles.
The Composition of Cartilage in Joints Changes
The composition of joint cartilage changes, these changes include a reduction in type 1 collagen and chondroitin sulphate affecting the elasticity and strength of the cartilage. This results in cartilage being more prone to damage and limited in ability to regenerate in response to intense activity or trauma.
Bones Become More Fragile
With a change in mineral uptake in older dogs over a long period skeletal mass can reduce due to reabsorption of bone. The cortices of long bones become thinner and more brittle.
Proprioception
As a dog ages they have less spindle cells in their muscles. Spindle cells are responsible for telling the body where they are in space and time which is known as proprioception. This can result in a less co-ordinated gait, the occasional trip or stumble and lack of body awareness.
Nerve Degeneration
Sensory nerves diminish resulting in less sensory input to the brain, the motor nerves also decrease in function resulting in reduced control of muscle contractions.
Cardiac Output
Vascular changes occur as a dog ages, alongside the loss of cardiovascular reserve and adaptability. This affects cardiovascular output, therefore a dogs ability to exercise may be affected.
Osteoarthritis
Osteoarthritis (OA) is not specifically an age-related change as dogs of any age can have OA, however prevalence is increased in our older dog population with 80% of dogs over 8 years old diagnosed with OA. It is one of the most common diseases in dogs.
There is a loss of joint cartilage, thickening of the joint capsule and new bone formation which leads to pain and limb dysfunction.
Sophie Sparrow BSc(Hons), DipAnPhys, RVN
RVN Pet Physio
