Skeletal System: Axial vs. Appendicular

Distinctive Bone Markings

• Distinctive bone markings denote surface features essential for bone identification.
• Articulating surfaces are smooth areas where adjacent bones meet.
• Depressions provide space for bony articulations or muscular structures, example: lobes of the brain.
• Projections indicate attachment points for muscles, tendons, and ligaments.
• Openings and spaces serve as passageways for blood vessels and nerves.

Common Bone Markings

General Structure and Surfaces

• Condyle: Large, smooth, oval structure important for joint formation.
• Facet: Small, flat surface that aids in articulation.
• Head: A prominent rounded end of a bone (epiphysis) that forms joints.
• Trochlea: A smooth, grooved process resembling a pulley.
• Alveolus: Deep pit or socket found in the jawbone (maxilla or mandible).
• Fossa: Flattened or shallow depression on a bone's surface.
• Sulcus: Narrow groove that accommodates nerves or blood vessels.

Depressions

Projections

• Crest: A prominent ridge on a bone's surface.
• Epicondyle: Projection located adjacent to a condyle, serving as an attachment site.
• Line: A low ridge along a bone.
• Process: Any notable protrusion on a bone structure.
• Ramus: Angular extension of a bone relative to the main body.
• Spine: A sharp, slender bony projection.
• Trochanter: A large, rough projection found only on the femur, significant for muscle attachment.
• Tubercle: A small, rounded projection on a bone.
• Tuberosity: A larger, rough projection for muscle attachment.

Openings and Spaces

• Canal: A passageway within a bone.
• Fissure: A narrow, slit-like opening indicating space in bone structure.
• Foramen: Rounded passage for nerves or blood vessels through a bone.
• Meatus: A tunnel-like passageway through the bone.
• Sinus: A cavity or hollow space within a bone, often for air or mucus.

Illustrations

• Skull, Anterior View showcases features like fissures and ramus.
• Skull, Sagittal View highlights sinus, process, foramen, and alveolus.
• Humerus displays tubercle, sulcus, head, tuberosity, fossa, trochlea, and epicondyle.

Distinctive Bone Markings

• Distinctive bone markings denote surface features essential for bone identification.
• Articulating surfaces are smooth areas where adjacent bones meet.
• Depressions provide space for bony articulations or muscular structures, example: lobes of the brain.
• Projections indicate attachment points for muscles, tendons, and ligaments.
• Openings and spaces serve as passageways for blood vessels and nerves.

Common Bone Markings

General Structure and Surfaces

• Condyle: Large, smooth, oval structure important for joint formation.
• Facet: Small, flat surface that aids in articulation.
• Head: A prominent rounded end of a bone (epiphysis) that forms joints.
• Trochlea: A smooth, grooved process resembling a pulley.
• Alveolus: Deep pit or socket found in the jawbone (maxilla or mandible).
• Fossa: Flattened or shallow depression on a bone's surface.
• Sulcus: Narrow groove that accommodates nerves or blood vessels.

Depressions

Projections

• Crest: A prominent ridge on a bone's surface.
• Epicondyle: Projection located adjacent to a condyle, serving as an attachment site.
• Line: A low ridge along a bone.
• Process: Any notable protrusion on a bone structure.
• Ramus: Angular extension of a bone relative to the main body.
• Spine: A sharp, slender bony projection.
• Trochanter: A large, rough projection found only on the femur, significant for muscle attachment.
• Tubercle: A small, rounded projection on a bone.
• Tuberosity: A larger, rough projection for muscle attachment.

Openings and Spaces

• Canal: A passageway within a bone.
• Fissure: A narrow, slit-like opening indicating space in bone structure.
• Foramen: Rounded passage for nerves or blood vessels through a bone.
• Meatus: A tunnel-like passageway through the bone.
• Sinus: A cavity or hollow space within a bone, often for air or mucus.

Illustrations

• Skull, Anterior View showcases features like fissures and ramus.
• Skull, Sagittal View highlights sinus, process, foramen, and alveolus.
• Humerus displays tubercle, sulcus, head, tuberosity, fossa, trochlea, and epicondyle.

Bone Markings

• Distinctive surface features characterize each bone in the body.
• Articulating surfaces between adjacent bones are typically smooth for joint movement.
• Depressions on bones create space for articulations and attachments of muscles or other components.
• Projections from bones indicate attachment points for muscles, tendons, and ligaments.
• Openings and spaces in bones serve as passageways for blood vessels and nerves.

General Structure

• Articulating Surfaces:*
• Condyle: Large, smooth, rounded, oval structure facilitating joint movement.
• Facet: Small, flat surface enabling articulation between bones.
• Head/Trochlea: Prominent rounded epiphysis, contributing to the formation of joints.
• Alveolus: Deep pit or socket found in the maxillae or mandible, housing teeth.
• Depressions:*
• Fossa: Flattened or shallow depression in bone contributing to joint formation.
• Sulcus: Narrow groove providing pathways for neurovascular structures.
• Projections:*
• Crest: Narrow, prominent ridgelike projection serving as a muscle attachment.
• Epicondyle: Projection located adjacent to a condyle, enhancing muscle leverage.
• Line: Low ridge marking an area for muscle attachment.
• Process: General term for any marked bony prominence.
• Spine: Pointed, slender projection often serving as a muscle attachment point.
• Trochanter: Massive, rough projection only found on the femur, aiding muscle attachment.
• Tubercle: Small, round projection for muscle attachment.
• Tuberosity: Large, rough projection providing a strong attachment site for tendons.
• Openings and Spaces:*
• Canal: Passageway through a bone allowing for blood vessels and nerves to travel.
• Fissure: Narrow, slitlike opening providing sites for nerve passage.
• Foramen: Rounded passageway through a bone for blood vessel and nerve entry.
• Meatus: Passageway through a bone, typically leading to an internal cavity.
• Sinus: Cavity or hollow space within a bone, often linked to the respiratory system.

Anatomical Terms

• Ramus: Angular extension of a bone relative to the rest of the structure, assisting in articulation and muscle attachment.

Skull

• Anterior view of the skull illustrates the arrangement of facial bones and teeth.
• Sagittal view of the skull presents the bone structure from a lateral perspective.