Nighttime leg burning sensations can indicate that you have a serious underlying medical condition. Burning pain in your thighs is called meralgia paresthetica. If your leg becomes swollen or traumatised in some fashion, pressure on the nerves results in pain, including a burning sensation, as well as causing paralysis and others types of dysfunctions in your leg.
The website of the American Academy of Orthopaedic Surgeons explains that nerves transport information to your brain, telling the brain to activate your motor nerves. In order for this process to be achieved, nerves have to pass under, over, through and around your bones, muscles and joints. If all is well within your system, there is room for these nerve transmissions to pass easily. However, if your leg has sustained damage, the nerves cannot transmit properly, and that is when pain occurs.
When your leg is burning on the outer thigh, whether it occurs at night or during the day, the lateral femoral cutaneous nerve is compressed or squeezed. The LFCN is the biggest sensory nerve in your legs. The burning sensation can extend to the outer side of your knee. Your groin may also ache, and your buttocks may hurt. Generally, the burning sensation is only on one side of the body. Nerve entrapment, or pressure, that is directly applied to a nerve or to a spinal attachment of that nerve can result in paresthesia, or the burning, creeping, tingling, pins and needles sensation that some individuals experience at night.
Paresthesia usually occurs in the extremities and can be an indicator of a serious disease, condition or disorder, or, on the other hand, a condition that it not so serious. Paresthesia may result from an infection, if you are experiencing inflammation in your joints and muscles or as the result of trauma or a malignancy.
Along with the burning feelings, comes numbness and tingling in the affected area. Touching the area, even lightly, will hurt. In fact, a light touch may hurt even more than firm pressure being applied to the affected area.
Nighttime leg burning sensations can be the result of conditions such as diabetic neuropathy, diabetes, neuropathy or multiple sclerosis.