The obturator nerve
arises from the second, third and fourth lumbar nerves
lies above the obturator vessels on the lateral wall of the pelvis
supplies the obturator internus muscle
has no sensory branches
supplies the gracilis muscle
The deltoid
initiates abduction of the shoulder
has an extensive range of action because it is multipennate
is supplied by the radial nerve
inserts into a rough elevation on lateral aspect of humerus
together with the head of humerus, it is responsible for the characteristic roundness of the shoulder
The axillary artery
begins at the upper border of the clavicle
terminates as it crosses the inferior border of pectorals minor
is contained in the axillary sheath
has the median nerve anterior to its proximal third
has the radial nerve behind its distal third
The biceps brachii
flexes both the shoulder and the elbow joints
both supinates and pronates the forearm
short head arises from clavicle
tendon of long head is partially enclosed in synovial membrane
is supplied by the median nerve
In the adult vertebral column
the primary curves are in the thoracic and sacral region
there is more flexion and extension in the lumbar region than in the thoracic region
there is more rotation about a longitudinal axis in the thoracic region than in the lumbar region
the transverse processes are posterior to the articular processes in all the vertebrae
the shape of the intervertebral discs contributes to the secondary curves