Autonomous Sensory Zones of Peripheral Nerves
Autonomous Sensory Zones of Peripheral Nerves Definition: These are the regions where single nerve roots supply distinct and non-overlapping areas of skin. By their nature the “autonomous zones” represent only a small portion of any dermatome and only a few nerve roots have such autonomous zones. The size of autonomous zone for a particular nerve is variable from individual to individual. Sensory zones of a Peripheral nerve: Maximal zone: Maximal area supplied by a peripheral nerve Intermediate zone: Area of overlap of the maximal zone of different peripheral nerves Autonomous zone: Area exclusively supplied by a particular peripheral nerve Note: Maximal zone = Intermediate zone + Autonomous zone With the interruption of a sensory nerve, all modalities of cutaneous sensation are lost only over the autonomous zone. Within a few days of complete interruption of a sensory nerve, the autonomous zone shrinks and the intermediate zone enlarges, which may be due...