HAP

• Objectives


  • Identity the parts of axial bones in a human body
  • Students should be able to understand and identify: The parts of the skull and its sutures
  • The different facial bones and their functions
  • Hyoid bone and its bony projection
  • Vertebral column and its parts
  • Classification of Ribs
  • Sternum and its parts
• Axial skeleton


  Forms the central axis of the body, protects the brain, the spinal cord, and the vital organs housed within the thorax
• Components of the axial skeleton

  • Skull
  • Vertebral column
  • Thoracic cage
• Skull


  22 bones divided into those of a braincase (neurocranium) and those of the face (viscerocranium)
• Cranial bones (neurocranium)


  • 8 bones that immediately surround and protect the brain
• Facial bones (viscerocranium)


  • 14 facial bones that form the structure of the face
• Sutures


  Immovable joints that connect the bones of the skull
• Four principal sutures


  • Coronal suture
  • Sagittal suture
  • Lambdoid suture
  • Squamosal suture
• Cranial bones


  • Frontal, Parietal, Temporal, Occipital, Sphenoid, and Ethmoid Bone
• Parietal bones


  • Make up the majority of the lateral portion of the skull, along with the temporal bones
  • Joined by the sagittal suture
  • Connected to the occipital bone by the lambdoid suture
  • Function is to help shape the head and protect the right and left parietal lobes of the brain
• Temporal bones


  • Connected to the skull by the squamous sutures
  • Primarily responsible for protecting the temporal lobe of the brain as well as the cranial nerves
  • Three main regions: Squamous, Tympanic, Petrous
• Frontal bone


  • Connected to the two parietal bones by the coronal suture
  • Forms the roof of both the orbit of the eye and the nasal cavity
  • Function is to protect the frontal lobe of the brain
• Occipital bone


  • The most posterior cranial bone
  • Makes up the majority of the skull's posterior wall and base
  • Most prominent feature is the foramen magnum (large hole)
  • Primary function is either for protection or to provide a broad surface for muscle attachment
• Sphenoid bone


  • Resembles a butterfly when viewed as a whole
  • Anterior to the sphenoid bone is the zygomatic bone or cheekbone
  • Helps form the base and lateral sides of the skull in combination with the orbital floor
• Ethmoid bone


  • A very porous, fragile bone
  • Centrally located in the skull, forming the nasal septum (wall), a large portion of the nasal cavity, as well as the medial wall of the orbits
  • Functions to direct and condition inhaled air from the nostrils to the nasal cavity to the lungs
• Facial bones


  • Nasal, Mandible, Vomer, Inferior Nasal Conchae, Zygomatic, Maxillae, Palatine, and Lacrimal Bones
• Nasal bone


  • Along with the frontal processes of the maxillae, form the bridge of the nose
  • Main function is to form the external surface of the nose, nasal aperture, and to protect the nasal cavity from external factors
• Mandible


  • The only skull bone that is freely movable relative to the other skull bones
  • Inferior to the maxillae and attaches posteriorly to the temporal bone via the mandibular
  • Functions as passage of nerves and blood vessels to the chin
• Vomer bone


  • Forms most of the posterior portion of the nasal septum
  • Main job is to help support the structure of the nasal passages and face
• Inferior nasal conchae


  • One of the three conchae in the nasal cavity that provide increased surface area, thus providing for rapid warming and humidification of air as it passes to the lungs
• Appendicular Skeleton


  The parts of the skeleton that are not part of the axial skeleton (skull, hyoid, auditory ossicles, ribs, sternum)
• Zygomatic bones


  • Commonly known as the cheekbones, are anterior to the sphenoid bone
  • The temporal process of the zygomatic bone articulates with the zygomatic process of the temporal bone to form the zygomatic arch
• Maxillae


  • The bones that form the upper part of the jaw, the roof of the mouth, and parts of the eye socket and nose
  • Holds the top teeth in place and supports muscles involved in chewing and facial expressions
  • A major bone in the face, also called upper jaw
• Clavicle


  • A bone of the shoulder that joins the breastbone and the shoulder blade
• Palatine bones


  • Have horizontal plates that fuse centrally to form the posterior portion of the hard palate
  • Participates in building the three cavities within the skull; the oral cavity, nasal cavity and the orbits
• Lacrimal bones


  • The paired facial bones and smallest of the skull bones
  • Main function is to provide support to the structures of the lacrimal apparatus, which secretes tears to lubricate the eyes, as well as act as a site for orbicularis oculi muscle attachment
• Cavities within the skull

  • Nasal cavity
  • Orbit
  • Paranasal sinuses
• Scapula


  • Also known as the "shoulder blade", is a flat, triangular bone located on the upper back. It connects the upper arm bone (humerus) to the collarbone (clavicle) and provides attachment points for various muscles.
• Nasal cavity


  • The space inside the nose
  • Main job is to warm, humidify, and filter (through the hairs and mucus) air before it enters the body
  • Has a rounded opening anteriorly and is separated into right and left halves by the nasal septum
• Humerus


  • The humerus is the long bone of the upper arm, extending from the shoulder to the elbow. It articulates with the scapula at the shoulder joint and with the radius and ulna at the elbow joint.
• Radius


  • One of the two bones of the forearm, located on the thumb side. It runs parallel to the ulna and is involved in the formation of the wrist joint and elbow joint.
• Orbits


  • Cone-shaped fossae bony structures that protects the globe, or the organ of sight also known as eyeball
  • Each orbit has seven bones
• Ulna


  • The other bone of the forearm, located on the pinky side. It runs parallel to the radius and forms the elbow joint with the humerus.
• Paranasal sinuses


  • A group of four paired air-filled spaces that surround the nasal cavity
  • Functions: Decreasing the relative weight of the skull, Increasing the resonance of the voice
• Carpals


  • A group of eight small bones that form the wrist. They provide flexibility and support to the hand and are arranged in two rows.
• Hyoid bone


  • An unpaired, U-shaped bone that does not articulate with another bone
  • Important for speech and swallowing
• Metacarpals


  • The five long bones that form the palm of the hand, connecting the carpals to the phalanges (finger bones).
• Vertebral column


  • Also known as spine, the central axis of the skeleton, extending from the based of the skull to slightly pass the end of the pelvis
  • Five major functions: Supports the weight of the head and trunk, Protects the spinal cord, Allows spinal nerves to exit the spinal cord, Provides a site for muscle attachment, Permits movement of the head and trunk
• Phalanges


  • The bones of the fingers. Each finger has three phalanges (proximal, middle, and distal), except for the thumb, which has two.
• Femur


  • The thigh bone.