◊ Nerves Affections ◊
AFFECTIONS OF THE NERVES
It is a process through which the nerve is compressed against blunt hard objects for a period long enough to cause paralysis of the innervated organs. Clear example of that is compression of radial nerve during casting of the animal on lateral recumbency for long period during surgery leading to paralysis of the extensors of corresponding limb.
Pressure is the main cause (as with radial or facial nerve)
Paralysis of the innervated muscles if the nerve is motor and loss of sensation if the nerve is sensory
1-Application of counter irritants and massage over the nerve course
2-Supportive treatment (bandaging the limb)
3-Injection of nerve tonics (Vit B12, Strychnine, or arsenical preparations)
4-Treatment of the affected muscle to avoid atrophy
Contusions usually affect superficial nerves
1-General symptoms of contusion and inflammation
2-Paralysis of muscles (motor nerves) and loss of sensation (sensory nerves)
3-Pain at the nerve
1-Promoting absorption of inflammatory exudates
3-Treatment of the paralyzed nerve and muscles
Nerves may be subjected to different types of wounds either by external objects or by internal exciting causes like bone fragment during fracture. These wounds may lead to partial or complete severing of the nerve.
Most nerves undergo regeneration following injury by swelling of the stump of the nerve with formation of neuroma, however suturing of the nerve and injection of nerve tonics promote healing of regenerative nerves.
IV-NEURITIS AND NEURALGIA
Neuritis is an inflammation of a nerve or group of nerves, characterized by pain over the nerve, loss of reflexes, and atrophy of the affected muscles.
Neuralgia is a chronic pain of unknown cause, and without inflammation, in the area covered by a peripheral sensory nerve. It appears as attacks of severe shooting pain along the nerve with weeks or months apart, but over time they become more frequent. Analgesics help, but permanent cure requires surgery.
Neuritis and neuralgia affect the peripheral nerves (the nerves that link the brain and spinal cord with the muscles, skin, organs, and all other parts of the body). These nerves usually carry both sensory and motor fibers; hence both pain and some paralysis may result.
The cause of neuritis may be mechanical, vascular, allergic, toxic, metabolic, or viral, while neuralgia has no definite cause.
Affection of sensory nerves causes tingling, burning, or stabbing pains while affection of motor nerves causes weakness to paralysis of the muscle that is usually confined to the part of the body served by the inflamed nerve.
1-Once the underlying cause is treated, recovery is usually rapid but may be incomplete in severe cases, with residual motor and sensory disturbances
2-Analgesics can relieve the pain
3-Treatment of the wound if present
However with neuralgia, it is often difficult to diagnose, and most treatments show little or no effectiveness. Neuralgia is more difficult to treat than other types of pain because it does not respond well to normal pain medications.
The primary lesion may be in the brain, spinal cord or peripheral nerve. When the affected nerve is motor nerve, the innervated muscle has no ability to contract, and when the affected nerve is sensory nerve, the innervated region suffers from permanent analgesia.
2-Counter irritants over the nerve and massage
3-Application of usual remedies to the innervated muscles
It is discussed under the topic tumor