Meralgia Paresthetica

(Lateral Cutaneous Nerve of the Thigh Entrapment)
Meralgia Paresthetica

This sensory nerve originates from the second and third lumbar roots and supplies the anterolateral aspect of the thigh from the level of the inguinal ligament almost to the knee. Compression (entrapment) may occur at the point where it passes between the two prongs of attachment of the inguinal ligament.
Compression of the nerve results in uncomfortable paresthesias and sensory impairment in its cutaneous distribution, a common condition known as meralgia paresthetica .Usually numbness and mild sensitivity of the skin are the only symptoms but occasionally there is a persistent distressing burning pain. Perception of touch and pinprick are reduced in the territory of the nerve; there is no weakness of the quadriceps or diminution of the knee jerk. The symptoms are characteristically worsened in certain positions and after prolonged standing or walking. Occasionally, for an obese person, sitting is the most uncomfortable position. Obesity, pregnancy, and diabetes mellitus may be contributory factors. Most often the neuropathy is unilateral but Ecker and Woltman found 20 percent of their patients to have bilateral symptoms.
Most of our patients with meralgia paresthetica request no treatment once they learn of its benign character. Weight loss and adjustment of restrictive clothing or correction of habitual postures that might compress the nerve are sometimes helpful. A few with the most painful symptoms have demanded a neurectomy or section of the nerve, but it is always wise to perform a lidocaine block first, so that the patient can decide whether the persistent numbness is preferable. Corticosteroid injections at the point of entrapment may have helped in a few cases but this has not been studied in a systematic way.