According to current accounts of the nerves in the vertebral canal, based mainly on the work of von Luschka (1850)1and Rüdinger (1863),2a recurrent or meningeal nerve arises from the communicating ramus of every spinal nerve and enters the vertebral canal through the corresponding intervertebral foramen. Within the vertebral canal these nerves bifurcate, sending a short division cephalad and another caudad. These divisions constitute a longitudinal strand of nerve fibers, the sinuvertebral nerve, located in the lateral region of the floor of the canal. Branches arising from the sinuvertebral nerve convey fibers to the meninges, to the blood vessels within the canal and to the membranes enveloping the spinal nerve roots. Certain clinical observations reported by Simpson, Brown and Adson (1930),3White (1933),4Telford (1934)5and others support the assumption that in certain cases some sympathetic fibers in the upper extremity remain functionally intact