Pain in the right lateral thigh may be caused by lumbar disc herniation, muscle strain, dermatomyelitis, and so on. 1. Herniated lumbar disc: If a herniated lumbar disc presses on a nerve root, it can lead to symptoms of pain in the area of the outer thigh that it innervates. 2. Muscle strain: muscle strain may cause pain, and the strain may also cause small blood vessels to rupture and bleed, resulting in localized edema and aseptic inflammation, which may cause pain. 3. Dermal neuritis: If you suffer from dermal neuritis of the right lateral thigh, pain may occur due to inflammatory stimulation. There are many causes of this symptom, it is recommended that people with right lateral thigh pain go to a regular hospital in time to clarify the cause of the disease and standardize the treatment under the guidance of the doctor.