vertebral column
How many vertebrae are in the adult vertebral column, and what are the five regions?
33 total: 7 cervical, 12 thoracic, 5 lumbar, 5 sacral, 4 coccygeal.
What are the three major groups of back muscles?
Superficial, intermediate, and deep.
How many pairs of spinal nerves are there?
31 pairs
What major artery travels through the transverse foramina of the cervical vertebrae?
Vertebral artery.
What are the four rotator cuff muscles?
Supraspinatus, infraspinatus, teres minor, and subscapularis.
What are the four major parts of a typical vertebra associated with the vertebral arch/processes, and what structures form the vertebral foramen?
Transverse process, spinous process, lamina, and pedicle; the vertebral body, pedicles, and laminae surround/form the vertebral foramen.
Are the superficial back muscles intrinsic or extrinsic, and what is their general function?
Extrinsic; they produce and control limb movements.
At approximately what vertebral level does the adult spinal cord terminate?
L1–L2, commonly around L2.
What is the primary movement at the atlanto-occipital joint?
Flexion and extension in the sagittal plane, the “yes” motion.
What does the glenoid cavity articulate with?
the head of the humerus
What are the two major joints between adjacent vertebrae?
Intervertebral disc joints between vertebral bodies and facet/zygapophyseal joints between articular processes.
What are the three major groups/layers of the deep intrinsic back muscles?
Splenii, erector spinae, and transversospinalis.
Why do the lumbar and sacral nerve roots descend within the vertebral canal before exiting?
During development, the vertebral column grows faster than the spinal cord, so the lower nerve roots elongate and descend to reach their corresponding intervertebral foramina.
What is the primary movement at the atlanto-axial joints?
Rotation in the transverse plane, the “no” motion.
What nerve innervates serratus anterior?
Long thoracic nerve, C5–C7.
What are the two main components of an intervertebral disc?
Outer anulus fibrosus and inner nucleus pulposus.
What structure surrounds and supports the intrinsic back muscles and has anterior, middle, and posterior layers?
Thoracolumbar fascia
What is the collection of lumbar, sacral, and coccygeal nerve roots below the spinal cord called?
Cauda equina.
What does the anterior atlanto-occipital membrane connect?
The anterior arch of C1 to the anterior margin of the foramen magnum.
What can result from injury to the long thoracic nerve?
Weakness/paralysis of serratus anterior causing a winged scapula.
What ligament connects adjacent laminae and helps prevent hyperflexion?
Ligamentum flavum.
What are the three columns of the erector spinae muscle group, listed from lateral to medial?
Iliocostalis, longissimus, spinalis.
What is the major segmental artery that reinforces blood supply to the inferior two-thirds of the spinal cord?
Artery of Adamkiewicz.
What is the suboccipital nerve?
What is the greater occipital nerve?
What is the least occipital nerve?
The dorsal ramus of C1.
The dorsal ramus of C2; it provides cutaneous innervation to the posterior head.
The dorsal ramus of C3; it provides cutaneous innervation to the posterior neck and head.
What structures pass through the quadrangular space?
Axillary nerve and posterior circumflex humeral artery.