As your dog ages, his body shows the physical signs of growing older, such as a gray muzzle, cloudy eyes, thickened toenails and a loss of muscle tone. This muscle atrophy may not necessarily be a part of normal aging, though; it can be a symptom of a medical problem that correctable through veterinary care.
Muscular atrophy is a weakening or wasting away of muscle mass. It can be observed as a loss of muscle tone and is most obvious on the hind legs and hips of senior dogs. Muscular atrophy has two main causes: lack of activity and disease, the two frequently working hand in hand. For example, a dog who is ill with a disease that weakens the muscles may become inactive, hastening muscular atrophy.
As your dog's body ages, he naturally experiences a small amount of muscular atrophy due to a lack of growth hormones and his body's changing ability to process protein. Less activity due to lower energy levels also leads to muscle loss in your senior dog. This normal muscle loss is mild and shows up mainly on his hind end, where muscling is most obvious. If your dog shows signs of significant muscular atrophy, or the loss is visible around his head and neck, it may be a sign of serious illness. Contact your veterinarian if you have any concerns.
Arthritis attacks the joints of older dogs, not the muscles, but can still lead to muscle atrophy. As arthritis degenerates the joint, often in your dog's hips and knees, it causes significant pain. This pain causes your dog to move stiffly and slowly, and makes him hesitant to play, run or exercise like usual. This decrease in activity, coupled with reluctance to stretch the muscles and use them fully, leads to muscular atrophy. Pain management medications as well as joint support and physical therapy can minimize the effects of arthritis, which in turn encourages your dog to exercise and restore his muscle mass.
Several serious ailments commonly seen in older dogs can lead to muscular atrophy. These include degenerative myelopathy, which is common in German shepherds but is also found in other breeds, hip dysplasia, intervertebral disc disease, and caudal cervical spondylomyelopathy, commonly known as wobblers. Treating the cause of the problem, such as repair surgery for hip dysplasia, can eventually improve your dog's muscle tone as he becomes more active.
In the absence of other problems, muscular atrophy is treated with regular exercise and weight loss. Your dog's activity level should increase gradually to give him time to become conditioned to additional exercise without becoming overly sore or uncomfortable. Extra weight puts pressure on your dog's joints and makes movement more difficult, so losing weight encourages him to move and exercise more, in turn reducing muscular atrophy. Consult with your veterinarian to create a proper exercise and diet schedule for your dog.
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