The clinical symptoms of numbness in the lateral thigh epidermis are commonly caused by the following: First, local trauma: a direct blow to the lateral thigh can cause serious local injury, and the patient will show clinical symptoms such as local swelling and numbness, mainly related to nerve compression, which can be quickly relieved by cold compress treatment and braking of the affected limb. Second, lumbar disc herniation or lumbar spinal stenosis: it can stimulate or compress the nerve, make the outer thigh skin sensation is reduced, and accompanied by lower limb muscle strength is weakened, the patient will also be accompanied by lumbar spine pain and lumbar spine activity is limited, through the MRI examination can find the lumbar spine nerve compression, through early treatment can improve the lumbar disc herniation, lumbar spinal stenosis, alleviate the clinical symptoms of numbness in the outer thigh. If the patient has the above symptoms, early diagnosis and early treatment is the only way to get quick relief of the symptoms.