Neuromuscular Disease

Loss of muscle function or strength in animals may be the result of neuromuscular disease. Because of recent advances in veterinary medicine, it is now easier to identify the various causes of disease and determine the best course of treatment. Every component of the complex neuromuscular system must work properly for signals to be sent and received accurately. While the brain is the control center for all neurological messages, the rest of the neurological information highway must be intact and operating normally for the neuromuscular system to function properly. When the brain sends an impulse to a muscle, that signal travels down the spinal cord, then along the peripheral nerves and across the neuromuscular junction (area of contact between the nerve and muscle) to make the muscle contract. In order for the brain to receive a message, the sequence is reversed: the impulse is initiated by a receptor, and then sent up the peripheral nerve and through the spinal cord of the brain (fig. 1). Disruptions can occur at any point along the neuromuscular system resulting in inappropriate on inadequate function of those parts of the body relying on accurate message transmission. Known diseases affecting the peripheral nerves of dogs include hypothyroid neuropathy, diabetic neuropathy, and immune mediated neuropathy, among others. There are many peripheral nerve diseases of unknown cause as well (idiopathic neuropathy).