Possible causes of numbness in the thigh include a thigh injury, cold temperatures and meralgia paresthetica, a disorder that occurs when the main nerve in the thigh, called the lateral femoral cutaneous nerve, becomes compressed, according to Healthgrades. Sciatica and peripheral neuropathy are other potential causes.
Numb thigh refers to a decreased sensation in the thigh resulting from nerve dysfunction or damage, explains Healthgrades. The symptom typically arises suddenly when caused by an injury. In contrast, numb thigh caused by an underlying neuropathy often progresses slowly and persists for a long period.
Lupus and multiple sclerosis are severe conditions affecting the nerves that can lead to numb thigh or legs, states Healthgrades. Sciatica, a condition that causes a numb, painful or weak leg, is associated with disc disease or spinal stenosis, which causes pressure on the sciatic nerve. Peripheral neuropathy results from disorders and diseases such as diabetes and alcoholism.
While rare, the occurrence of numb thigh along with numb or weak arms or legs on either side of the body may indicate stroke, notes Healthgrades. Anyone who experiences sudden thigh numbness along with weakness on a single side of the body, extremely painful headache or fading consciousness or alertness should call 911 for prompt medical care, as these warning signs and symptoms may signal the onset of a stroke.