Meralgia paraesthetica is a problem with a nerve (lateral femoral cutaneous nerve) that provides sensation to the outer thigh.
This nerve does not connect to any muscles, only the skin on the outer thigh, that is why it is called a cutaneous nerve which means skin. The nerve runs from the lower back where it starts, over the brim of the pelvic bone and down the outer thigh. Along the way, it can be compressed or knocked causing damage to the nerve.
This leads to a burning sensation on the outer thigh and may be associated with tingling or numbness.
This problem can usually be diagnosed by a clinical assessment in the doctor's office but nerve conduction studies may be required to confirm the diagnosis.