Sternomastoid paradox

In the standard routine for testing cranial nerve function following a cere brovascular accident (CVA) compromising the corticonuclear supply to the cr anial nerves, sternomastoid muscle ISM function is checked by means of head rotation against resistance. SCM appears to be an exception to the general ly contralateral motor weakness resulting from a CVA. The thrust of this ar ticle is that appearances can be deceptive: SCM is more likely to be a post ural stabilizer than a prime mover in head rotation. (C) 2001 Wiley-Liss. I nc.