Reread that quote from Breig's book, Skull Traction and Cervical Cord Injury.
Here it is:
From SKULL TRACTION AND CERVICAL CORD INJURY : Breig, 1989, Springer
Verlaag, Sweeden ------- 8 Therapeutic Breadth of Surgically Secured Spinal Cord Relaxation
Clinical experience with CLD (this is the operation in which Breig screws a ribbon to the head, threads it down to the thoracics, pulls the head into slight extension and ties off the ribbon to keep the head in slight extension and keep the cord and brainstem slack) over several years has confirmed that surgically secured slackening of the spinal cord can remove obstacles to the transmission of impulses along medullary pathways and can relieve neurological deficit, whether elicited by an offending lesion in the immediate vicinity of the cervical cord or by a lesion within its tissue. Besides slackening of overstretched nerve fibres, spinal cord relaxation also contributes to restoration of cord conductivity by increasing the oxygenation of medullary tissue, since it causes widening of the lumina of overstretched/constricted small blood vessels ; improved conductivity can be traced and followed by recording of evoked potentials. ....
The short story is that Breig made if plain that flexion of the spine or any part of it causes stretching of the cord and brainstem which gives rise to the neurological symptoms AND that those neurological effects and symptoms were consistently and predictably eliminated by the change in structure.
consistently and predictably makes the changes that reduce cord tension in human bodies. No one else even comes close to claiming it and no one says we cannot. Get at