Skeletal System Overview

Skeletal System Objectives

• Identify the bones of the human skeleton
• Describe the major bone markings

Readings

• Anatomy and Physiology text helpful throughout semester
• Online resources for specific bone groups (skull, thoracic cage, vertebral column, pectoral girdle, upper limb, pelvic girdle, and lower limb).

Skull Bones

• Frontal bone
• Ethmoid bone
• Occipital bone
• Temporal bone
• Sphenoid bone
• Parietal bone
• Lacrimal bones
• Palatine bone
• Nasal bone
• Maxilla
• Zygomatic bone
• Mandible
• Vomer bone
• Inferior nasal conchae

Extracranial Bones

• Mandible and hyoid bones. These bones are outside the cranium.

Neurocranium

• The neurocranium is the upper and back part of the skull, protecting the brain.
• It's also known as the braincase or brainpan.
• Bones of the neurocranium: ethmoid, frontal, parietal, occipital, sphenoid, and temporal bones.

Viscerocranium

• The viscerocranium forms the face and jaw, also known as the facial skeleton.
• Bones of the viscerocranium: 14 bones (6 paired and 2 unpaired): inferior nasal conchae, nasal bones, maxillae, palatine bones, lacrimal bones, zygomatic bones, mandible, and vomer.

Thoracic Cage and Vertebral Column

• Sternum
• Ribs
• Sacrum
• Coccyx
• Thoracic vertebrae
• Cervical vertebrae
• Lumbar vertebrae

Ribs

• True ribs (1-7): directly connected to the sternum via costal cartilage
• False ribs (8-10): connected indirectly to the sternum by connecting to the cartilage of rib 7
• Floating ribs (11-12): unconnected to the sternum or the cartilage of rib 7

Sternum

• Manubrium
• Body
• Xiphoid Process

Pectoral Girdle & Upper Limb

• Clavicle
• Scapula
• Humerus
• Radius
• Ulna

Hand Bones

• Carpal bones: Scaphoid, lunate, triquetral, trapezium, trapezoid, capitate, hamate, pisiform.
• Metacarpals: 1-5 (numbered starting from the thumb)
• Phalanges: Proximal, middle, distal (digits 2-5, 3 segments, 2 in the thumb)

Pelvic Girdle & Lower Limb

• Ilium
• Ischium
• Pubis
• Sacrum
• Coccyx
• Femur
• Tibia
• Fibula
• Patella

Foot Bones

• Tarsal bones: Talus, calcaneus, navicular, medial cuneiform, intermediate cuneiform, lateral cuneiform, cuboid
• Metatarsals: 1-5 numbered starting from the big toe.
• Phalanges: Proximal, middle, and distal (digits 2-5), proximal and distal (great toe)

Bone Markings

• Projections, depressions, or holes found on bone surfaces.
• Important for bone identification, joint formation, muscle attachment, and nerve/vessel passage.
• Two main categories: Projections and Depressions & Holes.
• Examples of Projections are Condyle, Epicondyle, Process, Protuberance, Tubercle, Tuberosity, Trochanter, Spine, Linea, Facet, Crests, and Ridges
• Examples of Depressions & Holes are Foramen, Fissure, Meatus, Fossa, Fovea, Incisure, Sulcus, and Sinus. More specifically, notches, meatuses, and external acoustic meatuses can be considered.

Additional Information

• Bone markings provide important identifiers for bones
• Bone markings enable joint formation and mobility
• Bone markings are critical for muscle connection and stabilization
• Bone markings facilitate nerve and vessel passage.