Back

External occipital protuberance: where is it, and which landmark is most visible with neck flexion?

The external occipital protuberance is the bony bump at the base of the skull. C7 (vertebra prominens) is most visible with neck flexion.

Surface landmark: superior angle of the scapula corresponds to which vertebral level?

T1

Surface landmark: inferior angle of the scapula corresponds to which vertebral level?

T7

Surface landmark: iliac crest corresponds to which vertebral level?

L4

Which surface landmarks can you palpate on the scapula?

Spine of the scapula, medial border, superior angle (T1), and inferior angle (T7).

How many vertebrae are in the vertebral column, and how many are movable vs. fused?

33 total: 24 movable and 9 fused.

List the vertebral regions and their counts.

Cervical C1-C7 (7), Thoracic T1-T12 (12), Lumbar L1-L5 (5), Sacrum S1-S5 (5, fused), Coccyx (4, fused).

What are the four roles of the vertebral column?

Protect the spinal cord and spinal nerves, posture, locomotion, and provide a flexible axis for the head and torso.

Which vertebral curvatures are primary, and what are their characteristics?

Thoracic and sacral. They develop early, are anteriorly concave, and produce a flexion position (kyphosis).

Which vertebral curvatures are secondary, and what are their characteristics?

Cervical and lumbar. They develop through antigravity positions (crawling), are posteriorly concave, and produce an extension position (lordosis).

What is normal thoracic kyphosis, and when is it excessive?

Normal is about 20-45 degrees; excessive is greater than 50 degrees. It can only be measured on radiograph.

What are the normal cervical and lumbar lordosis curvatures?

Cervical: 20-40 degrees. Lumbar: 40-60 degrees.

Define scoliosis and how it is identified.

Frontal plane deviation seen from a posterior view: lateral deviation of the column with a rotational component. Often identified by the forward bend test; may see a prominent shoulder blade, lean, or asymmetries.

What causes exaggerated lumbar lordosis?

Weakened abdominal muscles plus tight hip flexors, tensor fascia lata, and deep lumbar extensors.

What is a sway back posture?

A combination of lumbar lordosis and thoracic kyphosis that causes the hips to move anteriorly.

Sway back: which muscles are weak and which are tight?

Weak: lower abdominals, lower thoracic extensors, hip flexors. Tight: lower lumbar extensors, upper abdominals, hip extensors.

What is a flat back posture?

Decreased lumbar lordosis, causing the thoracic spine to move anteriorly and shift weight. Can cause difficulty standing upright, fatigue, and/or pain (opposite pattern of sway back).

What is the role of the vertebral body, and how does its size change down the column?

It is the anterior part of the vertebra and bears weight. Bodies increase in size from superior to inferior to support more weight.

What do the spinous and transverse processes do?

Serve as attachment points for muscles of the back and spine.

What do the articular processes form?

The facet (zygapophysial) joints, where each vertebra moves on the next.

What makes up a facet (zygapophysial) joint?

The inferior articulating processes of the superior vertebra and the superior articulating processes of the inferior vertebra.

Cervical facet joint orientation and movement?

About 45 degrees from horizontal (C2-C7). Permits flexion/extension; reduced rotation.

Thoracic facet joint orientation and movement?

Just off the frontal plane. Known for rotation; side bending is present but limited by ribs.

Lumbar facet joint orientation and movement?

Aligned with the sagittal plane. Promotes flexion and extension; reduced rotation.

What is the vertebral foramen (HOLE) and what forms it?

What if we say canal?

SEEN SUPERIOR / INFERIOR

Formed by the vertebral arch and posterior surface of the vertebral body; location of the spinal cord.

Multiple vertebral Foramens

Intervertebral foramen, what forms it, and what passes through it?

SEEN LATERALLY

Formed by the superior vertebral notch and inferior vertebral notch. Spinal nerves exit here.

Describe typical cervical vertebrae.

Seven vertebrae with small bodies; flexion/extension and limited rotation.

What passes through the transverse foramina?

What part of the spine is it in?

The vertebral arteries.

Cervical

What does the C0 on C1 (occiput on atlas) joint do?

Facilitates flexion/extension of the head (the 'yes' motion). Also called the atlanto-occipital joint.

What does the C1 on C2 (atlas on axis) joint do?

Facilitates rotation (the 'no' motion). Also called the atlanto-axial joint.

What is the vertebra prominens?

C7: the most prominent spinous process, most visible with neck flexion.

Describe C1

No vertebral body, no spinous process; ring-shaped with anterior and posterior arches.

(Atlas).

Describe C2

Has a dens (odontoid process) that articulates with C1. Developmentally, the C1 vertebral body becomes the dens.

(Axis)

What are uncovertebral joints (Joints of Von Luschka)?

SIDE TO SIDE MOTION

Joints between the uncinate processes of cervical vertebrae and the body of the adjacent vertebra. A site of bone spur formation due to friction.

How many thoracic vertebrae are there and what do they articulate with?

12 thoracic vertebrae articulating with 12 pairs of ribs.

Thoracic facet orientation and function?

Facets face upright; facilitate rotation with some lateral flexion limited by ribs.

Describe thoracic spinous processes.

Long, slender, and slanting inferiorly.

How do ribs articulate with thoracic vertebrae?

Each rib articulates with two vertebral bodies (the one with the same number and the one above) and the transverse process of the same-numbered vertebra.

Example: what does rib 7 articulate with?

The T6 and T7 vertebral bodies, and the T7 transverse process (via the tubercle of the rib).

Describe lumbar vertebral bodies

Large vertebral bodies

How does the lumbar vertebral foramen compare to other regions?

Larger than thoracic, smaller than cervical.

What two processes are unique to lumbar vertebrae?

Accessory process and mamillary process; both are multifidus (muscle) attachments.

Lumbar facet joint plane and facet directions?

Primarily sagittal plane

What movements do lumbar facet joints allow and prevent?

Flexion and extension, some lateral flexion; prevent anterior shear.

What type of joint is the lumbar facet joint?

A true synovial joint with a joint capsule.

What do interbody joints do?

Translate and tilt in all directions.

Describe the L5 vertebra.

Transitional vertebra with a wedge-shaped body and smaller spinous process. Superior disc surface is ~5% greater than inferior.

What is the lumbosacral angle? Normal and abnormal degrees?

Angle formed where L5 articulates with S1. Normal about 30-40 degrees; increased lordosis 50+ degrees, often with anterior pelvic tilt.

Describe the sacrum. Also which way do the Ramis go?

Five fused vertebrae with four pairs of anterior foramina (ventral rami) and four pairs of posterior foramina (dorsal rami).

What is the sacral hiatus?

Continuation of the vertebral canal to the inferior sacrum, covered by the sacrococcygeal ligament

Describe the coccyx, and what is it used for?

Inferior aspect of the sacrum; four fused vertebrae forming a triangular bone. Focal point for muscle and ligament attachments (sacrotuberous ligament, coccygeus muscle).

How are intervertebral discs named?

After the vertebrae surrounding them. Example: the C4/C5 disc is between C4 and C5.

How do disc shapes differ by region?

Cervical and lumbar discs are thicker anteriorly

Thoracic discs are relatively thin and uniform.

What is the anulus fibrosus?

what does it prevent?

DISC PART 1

Outer fibrocartilaginous ring arranged in concentric lamellae; resists tensile forces in nearly all directions. Concave posteriorly and reinforced to resist flexion.

(PREVENTS STRETCHING)

What is the nucleus pulposus?

DISC PART 2

Inner gelatinous mass that acts as a shock absorber and distributes forces. High water content that decreases throughout the day and with aging.

(PREVENTS COMPRESSION)

Anterior longitudinal ligament (ALL): features and function?

Strong and well developed in the lumbar region. Limits extension.

Posterior longitudinal ligament (PLL): features and function?

Thin in the lumbar region; helps prevent posterior disc protrusion. Limits flexion.

Ligamentum flavum: what does it connect and what does it do?

Connects lamina to lamina. Limits flexion.

Interspinous ligament: features?

Least overall stiffness. Limits flexion.

Supraspinous ligament: features?

Well developed in the lumbar region, terminates around L3-L4, reinforced by multifidus. Limits flexion.

Intertransverse ligament: function?

Limits contralateral lateral flexion (not a true ligament).

Iliolumbar ligament function?

resists anterior sliding of L5 on S1 and lateral flexion.

Tectorial membrane?

(CERVICAL SPINE)

Superior extension of the PLL in the cervical spine.

Nuchal ligament?

(CERVICAL SPINE)

Superior thickening of the supraspinous ligament.

Transverse ligament (cervical)?

holds the dens of C2 against the anterior arch of C1.

Alar ligament?

Reduces lateral flexion between the occiput and C2.

Innervation of the extrinsic (superficial) back muscles?

Ventral rami provide motor and sensory innervation; exception is trapezius, innervated by the accessory nerve (CN XI).

Innervation of the intrinsic (deep) back muscles, skin, and fascia of the back?

Dorsal rami.

Blood supply to the skin and fascia of the back?

Segmental vessels, branches of the intercostal and lumbar vessels.

What are the extrinsic back muscles' functions?

Which muscles are involved in respiration?

What innervates the upper traps / all others?

Influence the upper extremity in addition to the back; serratus posterior superior and inferior are involved in respiration.

cranial nerve 9 and accessory / peripheral off ventral rami

Describe the intrinsic back muscles?

Innervated by?

function bilateral and unilateral?

Longitudinal columns from skull to pelvis, protected by thoracolumbar fascia

innervated by dorsal rami; three layers.

Bilateral: extension.

Unilateral: lateral flexion and rotation.

Intrinsic superficial layer: muscles?

Splenius capitis and splenius cervicis.

Splenius capitis actions?

function bilateral and unilateral?

Bilateral: extension.

Unilateral: side bending and rotation of the head ipsilaterally.

Splenius cervicis actions?

function bilateral and unilateral?

Bilateral: extension.

Unilateral: side bending and rotation of the neck ipsilaterally.

What are the erector spinae muscles and what layer of deep muscles

Iliocostalis (lateral), longissimus (middle), spinalis (medial).

Intermediate

Erector spinae actions?

function bilateral and unilateral?

Bilateral: extension.

Unilateral: lateral flexion and rotation to the ipsilateral side.

Which muscles make up the deep intrinsic (transversospinalis) layer? and the function?

Semispinalis, multifidus, and rotatores (lie between transverse and spinous processes).

Function: extend and stabilize the vertebral column.

Semispinalis: location and region?

Most superficial of the transversospinalis group; most prominent in the cervical region.

Multifidus: region of prominence?

Lumbar region.

Rotatores: region of prominence and action?

Thoracic region; facilitate contralateral rotation.

Suboccipital Muscles Review:

1. Where are they located, and how many are there?

2. What nerve innervates them, and what type of nerve is it?

3. What are their primary actions?

• Count & Location: 4 muscles deep on C1–C2

• Nerve: Suboccipital nerve (C1) = MOTOR ONLY

• Action:

• Head extension (at OA joint)

• Same-side rotation (at AA joint - Inferior oblique

What are the borders of the suboccipital triangle?

Rectus capitis (posterior) major, superior oblique, and inferior oblique.

What is within the suboccipital triangle?

The vertebral artery and the suboccipital nerve

What is the greater occipital nerve and where does it sit?

Sensory only, from the dorsal ramus of C2; emerges inferior to the inferior oblique,

What is the thoracolumbar fascia made of, function (2)?

Network of collagen fibers;

superficial and deep layers support muscle attachments that allow the upper and lower body to work together through the lumbar spine.

Deep layers separate paraspinal muscles from the posterior abdominal wall.

What is the pars interarticularis?

The region between the superior and inferior articular facets; the weakest portion of the vertebral arch

Spondylolysis vs. spondylolisthesis?

Spondylolysis: pars fracture without anterior migration of the vertebral body

Spondylolisthesis: pars fracture with migration of the vertebral body.

Anterolisthesis vs. retrolisthesis?

Anterolisthesis: anterior slippage of the superior vertebra.

Retrolisthesis: posterior slippage of the superior vertebra.

Where are pars fractures most common and what do they cause?

Lumbar spine at L4-L5 and L5-S1. Can result in spinal stenosis and low back pain.

What is lumbar canal stenosis?

(BILAT) symptoms?

what makes it better ond worse?

Narrowing of the lumbar canal, congenital or acquired.

Symptoms: pain, numbness, or weakness in low back, legs, groin, hips.

Better = flexing

Worse = extension

Where are disc diagnoses common and what are the symptoms?

C5-C6 and L4-L5. Can press on nerves causing pain or nerve symptoms down the leg.

Disc degeneration?

Age-related changes.

Disc prolapse?

Disc position starts entering the spinal canal.

Disc extrusion?

Nucleus pulposus starts pushing through the anulus fibrosus.

Disc sequestration?

Nucleus pulposus enters the spinal canal.

What is a laminectomy?

Surgical removal of the lamina bilaterally (posterior structures of the spine) to take pressure off spinal nerves or spinal cord. Used for herniated disc, spinal stenosis, etc.

What is the triangle of auscultation?

A small region free of superficial muscles that allows improved auscultation of the lungs.

Borders of the triangle of auscultation?

Trapezius (medial), medial border of scapula (lateral), latissimus dorsi (inferior).

Vertebral arch and Body

Arch=protects the spinal cord

Body=allows for weight bearing of the spine on each subsequent level