Bone Surface Markings Overview

Overview

This lecture introduces the main surface markings on bones, categorizing them by type and function, and explaining their significance in anatomy.

Depressions and Openings

• Depressions and openings allow passage of nerves, blood vessels, ligaments, and tendons through bones.
• Fissure is a narrow slit permitting passage of nerves and blood vessels (e.g., superior/inferior orbital fissures).
• Foramen is a hole or opening in a bone, often for nerves/vessels (e.g., foramen magnum).
• Fossa is a shallow depression, not a hole, for bone articulation (e.g., mandibular fossa, glenoid fossa).
• Sulcus is a groove or furrow typically between elevated bone areas.
• Meatus is a tube-like passageway through bone (e.g., external auditory meatus).

Processes Forming Joints (Articulations)

• Condyle is a rounded, knuckle-like projection forming joints (e.g., occipital condyle, mandibular condyle).
• Facet is a smooth, flat articular surface for joint formation (e.g., vertebral facet).
• Head is a rounded bone end supported by a neck, forming part of a joint (e.g., head of femur, humerus, or radius).

Processes for Tendon or Ligament Attachment

• Crest is a prominent ridge for muscle/ligament attachment (e.g., hip bone crest).
• Spinous process is a sharp, slender projection (e.g., scapula, vertebra).
• Epicondyle is a raised area above a condyle (e.g., humerus epicondyle).

Other Bone Projections

• Trochanter is a large, blunt projection found only on the femur (greater/lesser trochanter).
• Tubercle is a small, rounded knob-like projection (e.g., on humerus).
• Tuberosity is a rough, bumpy area for tendon/ligament attachment (e.g., on radius, ischial tuberosity, tibial tuberosity).

Key Terms & Definitions

• Fissure — narrow slit for passage of nerves/blood vessels.
• Foramen — hole or opening for nerves/vessels.
• Fossa — shallow bone depression.
• Sulcus — groove or furrow in bone.
• Meatus — tube-like canal through bone.
• Condyle — rounded projection forming a joint.
• Facet — smooth flat surface for articulation.
• Head — rounded bone end for joint.
• Crest — prominent ridge.
• Spinous process — sharp, slender projection.
• Epicondyle — raised area above a condyle.
• Trochanter — large projection (femur).
• Tubercle — small, rounded projection.
• Tuberosity — rough, bumpy attachment area.

Action Items / Next Steps

• Review and memorize the definitions and examples of each bone marking.
• Practice identifying these markings on bone diagrams or models.