Causes of Leg Numbness
Leg numbness may be experienced as a tingly sensation, loss of sensitivity, or pins-and-needles perception. Temporary leg numbness is common after sitting on the leg for an extended period. This is due to pressure being placed on a nerve or lack of blood flow to the nerve. Leg numbness can also be the result of lower back problems.
Persistent numbness and tingling can be a sign of an underlying health condition. Common conditions that cause leg numbness include, but are not limited to, the following:
Sciatica, or sciatic nerve pain, refers to pain that occurs when the sciatic nerve root in the lower back becomes compressed, irritated or inflamed. Sciatic nerve pain radiates from the lower back, into the buttocks, and down the legs. It is most commonly the result of a herniated or slipped disc, bone spurs, or spinal stenosis.
Diabetes occurs when the body doesn’t make enough insulin or can’t effectively use insulin. Peripheral neuropathy is a medical condition that develops when the peripheral nerves are damaged due to diabetes. Numbness often begins in the toes and moves upward.
Multiple sclerosis (MS) is an autoimmune disease that affects the central nervous system. With MS, the immune system attacks the protective shell (myelin) of nerve fibers throughout the body. Scar tissue then accumulates around the nerves, which eventually causes nerve damage. Numbness is an early symptom of MS.
Peripheral nerve tumor
Although rare, a peripheral nerve tumor can develop near the nerves that control the leg muscles. Numbness due to a peripheral nerve tumor is frequently accompanied by swelling, loss of balance, a lump under the skin, or muscle weakness. It is usually non-cancerous, but can result in nerve damage.
Peripheral artery disease
Peripheral artery disease (PAD) occurs when plaque builds up in the arteries. This restricts blood flow to the lower legs, resulting in numbness. Other symptoms of PAD include hair loss and coldness of the lower legs.
Peripheral neuropathy is a medical condition that develops when the peripheral nerves are damaged. The peripheral nervous system is the communication network that connects the central nervous system (the brain and spinal cord) to every other part of the body.
Frostbite requires immediate medical treatment. It results from prolonged exposure to extreme cold conditions.
Physical activity can result in muscle strain, which often causes leg numbness. Resting and stretching should help with the numbness; however, if symptoms worsen, a health care professional should be consulted.
Pinched or damaged nerves
A pinched or damaged nerve, especially in the back can cause leg pain. Examples of pinched or damaged nerves include, but are not limited to, the following:
- The femoral nerve provides sensation to the thigh. Damage to this nerve can result in leg numbness. The numbness can occur in the thigh, knee, or entire leg.
- Tarsal tunnel syndrome (TTS) involves compression to the tibial nerve in the heel. The tibial nerve is located in the ankle and runs through the tarsal tunnel, which is a passage made of bones and ligaments. It can cause numbness in the feet.
- Meralgia paresthetica is a typical cause of numbness in the thigh. It occurs when the nerve that supplies skin sensation of the outer thigh becomes compressed.