Dorsal view, left side
Dorsal view, left side Cat information:
clavotrapezius (cat only � corresponds
to
the superior portion of the trapezius)
origin: superior
nuchal line of occipital
bone and the mid-dorsal line of
the neck to the
spine of the axis
insertion: clavicle
and the raphe between
the clavotrapezius and the
clavobrachialis
nerve: spinal accessory (XI) and ventral
rami of cervical vertebrae 1-4
action: elevates and retracts (adducts)
scapula
Posterior view, left
side
Posterior
(superficial) view of origin and insertion, left side
Superior view of superior division of the trapezius insertion, right side
Posterior (superficial)
view of insertion, right sideHuman information:
clavotrapezius (cat only � corresponds
to
the superior division of the trapezius)
origin: external occipital
protuberance,
medial third of superior nuchal line,
ligamentum nuchae, and spinous
process
of C7
insertion: lateral third of
clavicle and the acromion
process
nerve: spinal accessory (XI)
and
anterior rami of C3 and C4
(sensory component)
action: elevation and upward rotation
of
scapula,
when contracting with other portions of
the
trapezius it retracts (adducts) the
scapula
This is one of the five muscles that are grouped as muscles of the scapula, or sometimes as muscles that moor the scapula. The above drawing of the insertion on the clavicle might help visualize this information (blue is the insertion). The other drawings of the origin and insertion might help visualize this information (red is the origin and blue is the insertion). These other drawings are for the entire muscle and includes the origin and insertion for all three divisions of the trapezius muscle. Notice that part of the origin is on a ligament called the ligamentum nuchae, and this portion of the origin is represented by a line between the skull and the spinous process of C7. Thanks to Laura Holder for the excellent drawing!
COPYRIGHT
2009 by William C. Johnson II
ALL RIGHTS RESERVED!
