Thermatomes of the Lumbosacral Nerve Roots

ABSTRACT

Thermography shows the skin temperature changes in various conditions of the body. The skin temperature varies according to subcutaneous blood flow under the control of autonomic nervous system. Lumbar radiculopathy due to disc hernation makes difference in the temperature of lower extremities caused by the changes in general functions and autonomic functions of the nerve root. Digital infrared thermographic imaging(DITI) system has been used to diagnose radiculopathy without any hazards or discomforts and shows the pain due to LDH by objective change of temperature. This study has used DITIs of 55 control cases and 217 cases of LDH patients and analysed it statistically. In the room the temperature stable at 20 degrees C, the temperature distribution of the lower extremities of the control cases ranged from 24.9 degrees C to 29.9 degrees C. The significant minimal temperature difference between right and left lower extremities range from 0.1 degrees C to 0.4 degrees C. The more distal, the greater the temperature difference was. The thermatome of L4, L5 and S1 was drawn in radiating type and spot type. The thermatome showed larger area than the sensory dermatome and sympathetic dermatome. There was significant increase or decrease of temperature in thermatome in LDH patients. In conclusion, preoperative DITI of the LDH patient can be helpful for diagnosing the level of LDH and the areas of pain.