Additional Bone Resource.

Bone Markings Overview

  • All bones have distinctive markings or landmarks.

  • Markings serve specific functions such as attachment for tendons and ligaments.

  • Types of markings include:

    • Trochanters

    • Tubercles

    • Crests

    • Processes

    • Articulating surfaces for joints.

    • Depressions and openings for passageways for nerves and blood vessels (e.g., foramina, canals, fissures).

Common Bone Markings Examples

Skull Bones

  • Foramina (singular = foramen): Round or oval holes/openings.

  • Meatus: A bony passageway.

  • Sinus: A cavity within a bone.

  • Groove: Narrow channel.

Humerus Markings

  • Head: Rounded expansion connected to a narrow neck.

  • Epicondyle: Elevated bony projection above a condyle.

  • Trochlea: Pulley-shaped articular process.

Femur Markings

  • Trochanter: Large irregularly shaped process (unique to femur).

  • Fossa: Shallow depression.

  • Crest: Prominent narrow ridge.

Vertebra Anatomy

Typical Vertebra Structure

  • Anterior: Vertebral body is the main weight-bearing component.

  • Posterior: Vertebral arch, made up of the pedicles and laminae.

    • Pedicles: Lateral walls of the arch.

    • Laminae: Forms the roof.

  • Vertebral Foramen: Opening for spinal cord; progressively larger from superior to inferior vertebrae.

Bony Processes

  • Spinous process: Projects posteriorly from the fusion of laminae.

  • Transverse processes: Extend laterally from the vertebral arch.

  • Articular processes: Superior and inferior, for articulation between vertebrae.

Intervertebral Discs

  • Composed mainly of fibrocartilage, providing cushioning between adjacent vertebrae.

Thoracic Vertebrae

  • Count: 12 thoracic vertebrae, characterized by their articulation with ribs.

  • Structure:

    • Heart-shaped body and circular vertebral foramen.

    • Costal facets for rib articulation: Located on the body and transverse processes.

Sacrum Anatomy

  • Development: Composed of 5 vertebrae fused by mid-20s.

  • Features:

    • Sacral promontory: Important for obstetric measurements.

    • Sacral foramina: Openings for spinal nerves.

    • Median sacral crest: Formed from fused spinous processes.

  • Functional Advantage: Single large sacrum provides stability and supports weight transfer to ilium.

Thoracic Cage Relationships

  • Rib Attachments: Most ribs articulate with two thoracic vertebrae.

  • Rib Structure:

    • Identifiable sections: head, tubercle, and neck.

    • Costal groove: Pathway for intercostal vessels and nerves.

Cranial Cavity Overview

Bone Structure

  • Formed by Frontal, Ethmoid, Sphenoid, Temporal, Occipital, Maxilla, Zygomatic, and Palatine bones.

Markings on the Skull

  • Key markings include:

    • Supraorbital foramen

    • Superior orbital fissure

    • Optic canal

    • Infraorbital foramen

    • Mental foramen

Viewing the Skull

Posterior View Features

  • Occipital bone and portions of parietal bones form the posterior wall.

  • Notable sutures include:

    • Sagittal suture (between parietal bones)

    • Lambdoid suture (between parietal and occipital bones)

  • External occipital protuberance: Prominent landmark.

Cranial Cavity Floor Observations

  • Fossae: Anterior, middle, and posterior cranial fossae accommodate different brain lobes.

  • Sphenoid bone foramina include:

    • Optic canal

    • Foramen rotundum

    • Foramen ovale

    • Foramen spinosum

Cleft Palate Considerations

  • Failure to fuse maxillary bones at the midline can result in a cleft palate.

  • Anticipated issues before surgical correction.