KJ

Skull and Vertebral Column – Key Terms (Vocabulary)

Facial Bones (14 total)

  • Bones and counts
    • Nasal bones: 2
    • Inferior nasal conchae: 2
    • Maxilla (maxillae): 2
    • Zygomatic bones: 2
    • Lacrimal bones: 2
    • Palatine bones: 2
    • Mandible: 1
    • Vomer: 1
  • Summary mnemonic to remember the 14 facial bones
    • "Noah's nephews invited inside two monkeys, two zebras, two lions, two parrots, Martha bumped it." (a silly saying to recall nasal, inferior nasal conchae, maxilla, zygomatic, lacrimal, palatine, mandible, vomer)
  • Nasal bones
    • Form the bridge of the nose; left and right
    • The rest of the front part of the nose is elastic cartilage
  • Inferior nasal conchae
    • Small bones inside the nasal cavity; you can see a little hook on the bottom inside
  • Maxilla
    • Left and right; holds the upper teeth
  • Zygomatic bones
    • The cheekbones; contribute to facial width and contour
    • Mentioned as a characterizing feature for appearance (e.g., “cheekbone structure”)
  • Lacrimal bones
    • Tiny bones inside the orbit; contain a hole that leads tears to drain toward the nose (lacrimal fossa) as tears drain into the nasal cavity
    • Lacrimal gland is associated with tear production
    • Fossa means a depression
  • Palatine bones
    • Form the posterior portion of the hard palate; maxilla forms the majority of the hard palate
    • Cle­ft palate: a line down the center where these bones failed to fuse; surgical repair discussed
  • Mandible
    • The only movable bone of the skull; holds the lower teeth
  • Vomer
    • In the nasal opening; forms a vertical ridge
    • Memory cue: “vom­er means to vomit” (vomiting may occur through the nose when sick)
  • External skull features (top view and surrounding context)
    • Frontal bone, Parietal bones, Temporal bones, Occipital bone
    • “Fr” = Frontal; “Pa” = Parietal; “Te” = Temporal; “Oc” = Occipital
    • Sutures connect these bones and are important landmarks
  • What is a suture? and the major sutures
    • A suture is where the skull bones are stitched/fused together
    • Fontanels: soft spots in a baby’s skull that allow growth of the brain and skull proportionally
    • Sagittal suture: between the two parietal bones; can be described as midsagittal but not always exactly in the middle
    • Squamosal (squamosal) suture: between the temporal and parietal bones; “squamous” means flat (Latin root) and is the thinnest part of the skull
    • Lambdoidal suture: between the occipital bone and the parietal bones; named for an upside-down “Y” shape similar to the Greek letter lambda
  • Important external features on the posterior skull
    • External occipital protuberance: a bump on the external back of the skull (comedic “bump of knowledge” reference to learning)
  • Features behind the ear and in front of the ear
    • Mastoid process: a thick, chunky bump behind the ear; attachment point for neck muscles (e.g., sternocleidomastoid)
    • External acoustic meatus (external auditory meatus): the ear canal opening; contains a canal into the temporal bone; tip for using a Q-tip
  • The base of the skull features and their functional significance
    • Occipital condyles: rounded projections on the base of the skull that articulate with the first cervical vertebra; enable nodding movement
  • Foramen terminology (key openings in skull bones)
    • Foramen: a hole in a bone
    • Foramen magnum: the large opening at the base of the skull for the spinal cord and nerves
    • Sella turcica: a depression in the sphenoid bone that houses the pituitary gland (pituitary sits in the “turkish saddle”)
    • Foramen ovale: oval-shaped opening laterally near the maxilla; nerve passage
    • Foramen rotundum: round opening near the maxilla; nerve passage
    • Optic canal/foramen: the opening for the optic nerve (cranial nerve II) as it travels to the eye
    • Olfactory foramina: in the ethmoid bone (cribriform plate area) through which the olfactory nerve (cranial nerve I) passes; related to smell
  • Quick notes to help exam recall
    • The orbit contents and adjacent bones matter for lacrimal fossa and tears drainage
    • The ethmoid bone’s olfactory foramina are closely tied to smell perception
    • The sella turcica’s pituitary sits in a protected pocket
    • The skull’s sutures and fontanels reflect growth and protection of the brain in infancy
    • The mastoid process and external acoustic meatus relate to hearing and neck muscle attachments
    • The mandible’s mobility is unique among skull bones

The Vertebral Column and Its Major Features

  • Vertebrae counts by region (top to bottom)
    • Cervical vertebrae: 7
    • Thoracic vertebrae: 12
    • Lumbar vertebrae: 5
    • Sacrum: fused from 5 vertebrae into one sacral bone
    • Coccyx: fused from 4 vertebrae into one coccyx
  • Mnemonic for counts (from top to bottom)
    • “Breakfast, lunch, dinner” (cervical, thoracic, lumbar) to recall regional order and increasing size downward
  • General pattern of vertebrae sizes
    • Vertebrae get larger as you move downward to support increasing weight-bearing demands
  • The vertebral foramen
    • Each vertebra has a vertebral foramen (the hole) that together form the vertebral canal for the spinal cord
  • The vertebral column from a functional perspective
    • When viewed from the front, the spine should be straight like a steel bar
    • When viewed from the side, curvatures provide flexibility like a spring
  • Primary and secondary curves (developmental context)
    • Primary curve (kyphosis): present in the thoracic and sacral regions; the initial curvature in a baby
    • Secondary curves develop later as the child grows: cervical curvature as the baby lifts and holds the head up; lumbar curvature as the child begins to walk
  • Intervertebral discs
    • Between vertebrae are fibrocartilage discs (strong, resilient to compression)
    • Herniated/bulging discs occur when the disc protrudes and can compress neural structures
  • Vertebral features (common to all regions with regional variations)
    • Vertebral body: the thick, anterior portion bearing weight
    • Spinous process: projects posteriorly; can be felt along the midline of the back
    • Transverse processes: extend laterally from the sides
    • Superior articular processes (top): articulate with the vertebra above
    • Inferior articular processes (bottom): articulate with the vertebra below
  • Cervical vertebrae specifics
    • Cervical vertebrae have very short, stubby transverse processes
    • Transverse foramina: openings in the transverse processes for vertebral arteries and veins
  • Thoracic vertebrae specifics
    • Thoracic vertebrae have articulations with ribs; transverse processes extend more to the side and slightly backward for rib articulation
    • Rib head can slip out of place if misaligned (illustrated by the instructor with “rib head” analogy)
  • Lumbar vertebrae specifics
    • Lumbar vertebrae are the largest; strong, weight-bearing bones in the lower back
  • Sacrum and coccyx specifics
    • Sacrum: a large, triangular bone formed by the fusion of the five sacral vertebrae; contains sacral foramina for nerves but this model didn’t show all
    • Coccyx: the tailbone, formed by fusion of four coccygeal vertebrae
  • Spinal nerves and foramina between vertebrae
    • Intervertebral foramina: openings between adjacent vertebrae through which spinal nerves exit
  • Postural and biomechanical implications
    • Prolonged poor posture or uneven loading can pinch nerves via the intervertebral foramina
    • Pregnancy and childbirth can affect spinal integrity and muscular support; recovery may take about a year to regain structural integrity
  • Key clinical terms encountered in the lecture
    • Degenerative changes: Degenerative joint disease (DJD) and degenerative disc disease (often discussed in chronic pain contexts)
    • Scoliosis: lateral or sideways curvature of the spine; a reversible condition in early development; screening emphasized
  • Scoliosis screening demonstration (hands-on portion described)
    • Have the person stand straight with arms at sides, facing a board
    • Observe for shoulder/hip alignment, ear levelness, and any asymmetry
    • Bend forward to assess asymmetrical rib prominence or protrusions (as described with the teacher’s demonstration)
    • If a child shows a shoulder or hip imbalance, it could indicate scoliosis or muscular imbalance; in early development, such imbalances can be corrected with posture and strengthening exercises
  • Practical exercise and guidance given during the demonstration
    • Posture correction tips: stand with heels, butt, and head against a wall; push shoulders back to achieve a straight line from ear to shoulder to hip to ankle
    • If one side tends to be higher, it can reflect muscle imbalance or dominance and may require targeted strengthening of the opposing side
    • Shoe wear patterns can reveal imbalance (one side of the sole worn differently than the other)
  • Gender-related observations and caveats mentioned (contextual discussion)
    • Observations about scoliosis prevalence and differences in susceptibility discussed with caveats related to anatomy and biomechanics
    • Emphasis on posture and strengthening rather than attributing imbalance to gender per se
  • Summary of the biomechanical model of the spine used in the lecture
    • The spine acts as a balance between a rigid stabilizing structure (steel bar) and a flexible spring (curvatures)
    • Nerves exit between vertebrae through the intervertebral foramina and can be affected by disc health and alignment
  • Lab-related and study tips from the instructor
    • Check the module three lab checklist for foramina (e.g., foramen ovale, foramen rotundum, optic canal, olfactory foramina, foramen magnum) and identify the exact anatomical location on models
    • The idea of lab practice with skull models to reinforce bone landmarks and relationships
  • Closing note from the instructor
    • Monday’s plan to start the appendicular skeleton (the limbs) and continue exploring the full anatomy in more depth

Quick Reference: Key Terms and Landmarks (highlights)

  • Facial bones: 2 nasal, 2 inferior nasal conchae, 2 maxillae, 2 zygomatics, 2 lacrimals, 2 palatines, 1 mandible, 1 vomer
  • External skull landmarks: frontal, parietal, temporal, occipital; external occipital protuberance; mastoid process; external acoustic meatus
  • Senses and openings: olfactory foramina (smell) in the ethmoid; optic canal (vision) for the optic nerve; foramen magnum (spinal cord) in the occipital bone; foramen ovale and foramen rotundum near the sphenoid and maxilla
  • Sella turcica: housing of the pituitary gland in the sphenoid bone
  • Zygomatic arch and facial contour role; cleft palate (fusion failure in the center between maxilla and palatine)
  • Ver­tebral column anatomy: vertebral body, spinous process, transverse processes, superior/inferior articular processes, vertebral foramen; intervertebral foramen; cervical transverse foramina; kyphosis (primary curve); secondary curvatures forming in the neck and lumbar regions
  • Disc and nerve health: fibrocartilage intervertebral discs; bulging/herniated discs; nerves exiting via intervertebral foramina
  • Scoliosis screening cues: shoulder/hip/ear alignment; rib prominence on bending; posture correction exercises; gender-biased observations discussed with focus on mechanics
  • Notable analogies used in lecture: zigzag sutures as strong architectural joins; “bump of knowledge” on the external occipital protuberance; “turning the teeter-totter” as balance of spinal loading
  • Exam-oriented names/foramina to know (as referenced): foramen magnum, foramen ovale, foramen rotundum, optic canal/foramen, olfactory foramina, sella turcica, and the related cranial nerves they connect to (I, II, etc.)
  • Artistically, the lecture emphasizes practical understanding by pointing to physical models and demonstrations to connect anatomy with everyday function and clinical relevance