Lecture on the Appendicular Skeleton: The Foot

Overview

• Focus on the bones of the appendicular skeleton, specifically the foot.
• Discussion on the 52 bones that constitute the right and left feet.

Orientation of the Foot

• Superior Surface: Also known as the dorsal surface.
• Plantar Surface: The bottom surface of the foot.

Types of Bones in the Foot

• Tarsals: Similar to carpals in the hand but there are seven tarsals.
• Metatarsals: Five bones forming the anterior portion of the foot.
• Phalanges: Bones in the toes.

Detailed Bone Structure

Phalanges and Metatarsals

• First Digit (Big Toe):
  • First metatarsal.
  • Proximal phalanx 1 and distal phalanx 1.
• Other Digits:
  • Proximal, middle (where applicable), and distal phalanges for digits two through five.
• Metatarsals: Numbered one to five from medial (big toe) to lateral.

Tarsals

• Talus: Large bone on top forming the bulk of the ankle joint.
• Calcaneus: The heel bone.
• Cuboid: Cube-shaped bone next to the calcaneus.
• Navicular: Broad, flattened bone articulating with the talus.

Cuneiforms

• Three Cuneiforms:
  • First Cuneiform (Medial): Next to the first metatarsal.
  • Second Cuneiform (Intermediate): Next to the second metatarsal.
  • Third Cuneiform (Lateral): Next to the third metatarsal.

Key Points

• The calcaneus is associated with the heel.
• The talus articulates with the navicular.
• Cuboid is cube-shaped; navicular is more flattened.
• Navicular does not touch metatarsals, whereas the cuboid does.

Naming

• An alternative naming system uses medial, intermediate, and lateral for the cuneiform bones.