Transforaminal or translaminar approach for dorsal root ganglion and dorsal nerve root. Anatomical reason for technique decision

Abstract Radiculopathy is probably one of the most frequent types of pain seen in Pain Clinics. Invasive techniques such as transforaminal or translaminar injections are used when other conservative methods have failed. In these procedures, medication such as corticosteroids and local anaesthetics are injected next to the dorsal root ganglion and dorsal nerve root. The decision to use one or another approach depends on factors such as the region to treat (cervical, dorsal or lumbar), the characteristics and the cause of the pain. In this study we review the anatomical and histological aspects that can influence the decision to use each of these techniques for the treatment of radicular pain. We describe the morphology of the intervertebral foramen, its dimensions and the vascular supply of spinal cord and intervertebral foramen. We also analyze ultrastructural details that may help understand the role of spinal nerve root cuffs and other structures such as capillaries and fat that plays an important role on the spread of substances injected in the epidural space and in transforaminal blockade. This review includes a microscopic analysis of the corticosteroids used and in some cases related to the complications published.