Understanding Peripheral Neuropathy -- the Basics
The damage to the nerve can result in numbness, tingling, unusual sensations, and pain in the first three fingers on the thumb side of the hand. The person may awaken at night with numbness in their hand or discover that when they perform activities like using a hair dryer, the numbness is more noticeable. In time, carpal tunnel injuries can weaken the muscles in the hand. You may also feel pain, tingling, or burning in your arm and shoulder.
Here are examples of other mononeuropathies that can cause weakness in the affected parts of the body, such as hands and feet:
Ulnar nerve palsy occurs when the nerve that passes close to the surface of the skin at the elbow is damaged. The numbness is noted in the 4th and 5th digit of the hand.
Radial nerve palsy is caused by injury to the nerve that runs along the underside of the upper arm and can occur with fractures of the humerus bone in the upper part of the arm.
Peroneal nerve palsy results when the nerve at the top of the calf on the outside of the knee is compressed. This leads to a condition called "foot drop," in which it becomes difficult to lift the foot.
Neuropathy can affect nerves that control muscle movement (motor nerves) and those that detect sensations such as coldness or pain (sensory nerves). In some cases, it can affect internal organs, such as the heart, blood vessels, bladder, or intestines. Neuropathy that affects internal organs is called an autonomic neuropathy. This rare condition can cause low blood pressure or problems with sweating.
Polyneuropathy accounts for the greatest number of peripheral neuropathy cases. It occurs when multiple peripheral nerves throughout the body malfunction at the same time. Polyneuropathy can have a wide variety of causes, including exposure to certain toxins such as with alcohol abuse, poor nutrition (particularly vitamin B deficiency), and complications from diseases such as cancer or kidney failure.
One of the most common forms of chronic polyneuropathy is diabetic neuropathy, a condition that occurs in people with diabetes. It is more severe in people with poorly controlled blood sugar levels. Though less common, diabetes can also cause a mononeuropathy.