Origin: The spinous process of the axis vertebra.
Insertion - The lateral portion of the inferior nuchal line of the occiput
and the surface area below the line.
(Broadening as it ascends.)
Location: The rectus capitis posterior majors are readily accessible
for palpation because of their broadening insertion. The index fingers
are placed above the spinous process of axis (on either side of its apex)
and then running the fingers lateral, in each direction and slightly cranialward,
these bellies are located deep to the origin of the trapezius (though actually
separated from the trapezius by the semispinalis capitis).
Listing Involvement: Rectus capitis posterior major works on the opposite side of axis spinous deviation.
Working Sensation: The rectus capitis posterior majors are palpable
to a firm or rigid degree when found working. The muscle may be well
defined or seem only to blend with overlying muscle that runs relatively
in the same direction to its fibers. In either situation the rectus
capitis posterior major gives a "raised effect" as its fibers are traced
over the atlas posterior arch. This slightly elevated tension is characterized
by depth of touch and stalwart pliancy upon palpation.