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The Skeletal System

is the framework of bones and cartilage that protects organs and allows movement.


Regions of the Skeleton

The regions of the skeleton are:

  1. Axial Skeleton - forms the central axis
    • skull, hyoid, vertebral column, ribs, sternum and sacrum
  2. Appendicular Skeleton - includes the:
    • Pectoral Girdle

    • Upper Extremity

    • Pelvic Girdle

    • Lower Extremity


# of Bones

The human skeleton consist of 206 Bones in typical adult skeleton


Skull Sutures

There are 4 sutures moveable joints found only between skull bones:

  1. Coronal
  2. Sagital
  3. Lamboid
  4. Squamous


The Skull

The skull has 22 bones that held together by sutures:

  1. 8 Cranial Bones
  2. 14 Facial Bones


Skull - Cranial Bones

8 Cranial bones encloses the brain:

  1. Frontal
  2. Sphenoid
  3. Occiptal
  4. Ethmoid
  5. Temporal (2)
  6. Parietal (2)


Skull - Facial

The 14 Facial bones support Teeth & form Nasal Cavity, and no contact with the brain are:

  1. Nasal Bones (2)
  2. Maxilla (2)
  3. Zygomatic (2)
  4. Lacrimal (2)
  5. Palatine (2)
  6. Inferior Nasal Concha (2)
  7. Vomer
  8. Mandible


Temporal Bone + Ear Bone

There are (3) Three Parts to the Temporal Boxed Ear Bone:

  1. Squamous Part
    • Zygomatic Process
  2. Petrous Part
    • Ear
    • Styloid Pocess - for muscle attachment
  3. Mastoid Process
    • Looks like 


Occipital Bone

The occipital bone is at the rear of skull, two key parts of the occipital bone are:

  1. Foramen Magnum
    • This is where the Spinal Cord passes through
  2. Occipital Condyles
    • This is where the skulls rest on the Atlas vertibrate


Sphenoid Bone

The sphenoid bone is THE skull bone, it holds the:

  1. Body of the Sphenoid
    • Sella Turcia
    • Houses the Pituitary Glads
  2. Lesser Wing
    • Optica Foramen
  3. Great Wings
    • Foramen Rotundum + Ovale for trigeminal Nerve
    • Foramen Spinosum For Meningeal Artery


Ethmoid Bone

The Ethmoid Bone is the Stinky bone, it is:

  1. Found between the orbital cavities

  2. Forms lateral walls and roof of nasal cavity

  3. Crista galli is a structure inside the cranium

  4. Nasal Concha \ turbinates is on the lateral wall and protrudes into the breathing passage


Inferior Nasal Conchae

is a separate bone, thats Not a part of the ethmoid like the superior & middle concha


Hyoid Bone

The Hyoid Bone is a:

  1. Provides attachment for the tongue muscles, neck muscles
  2. U-shape bone
  3. It doesn't articulate with no other bone


Anterior Fontanel

The anterior fontanel is commonly called the “soft spot”

  1. It enables the Fetal Skull to get through the birth canal
  2. Allows for rapid brain growth
  3. Fuse to bone by age 2



Chiropractic (Chiro = hand, practic = done by)  it is a:

  1. a holistic, drugless science of  spinal care
  2. and it’s relationship to the nervous system and health


The Vertebrae Column

  1. There are 26 Moveable Vertebrae
  2. There are 33 Total Vertebrae


Vertebral Groups

There are (5) Five Vertebral Groups

  1. 7 Cervical in the Neck
    [7 Days in week]

  2. 12 Thoracic in the Chest
    12 Months of the Year]

  3. 5 Lumbar in Lower Back
    [5 working Days of week]

  4. 1 Sacrum (5 fused bones)

  5. 1 Coccyx (4 fused bones)
    [ 2 Day Week (Sacrum+Coccyx) ]


Spinal Curvatures

The adult spinal cord is a S-shped vertebrate that has 4 Curvatures.

  1. The Secondary Curvature, is developed after birth, and begins during crawling as baby begin living head.
  2. The Lumbar Curvature provides ability to walk upright



  1. The Sacrum has 5 Separate Sacral Vertebrae that are fused by age 26
  2. Sacral Canal starts at Top and Ends as the Sacral Hiatus

  3. Auricular surface is part of sacroiliac joint



The Coccyx is a single, small, triangular bone, it has:

  1. 4 Small vertebrae that are fused by age 30
  2. It is fractured by falls or during childbirth


Axis (C2)

Axis (C2 Vertebra) supports the first cervical vertebra (C1), it has:

  1. A vertebral body 
  2. The body of the Atlas is the Dens of the Axis
  3. The Dens or Odontoid Process is held in place inside the vertebral foramen of the atlas by Ligaments


Atlas (C1)

Atlas (C1) supports the Skull and has No Body, it is:

  1. It is comprised of two bony arches with two bony masses laterally.

  2. It articulates with the Occiput above and C2 (the Axis) below.



The humerus is a long bone which consists of a shaft (diaphysis) and two extremities (epiphysis). It is the longest bone of the upper extremity.

  1. The Head of the Humerus forms the shoulder joint with the Glenoid Fossa of the scapula
  2. Muscle attach to the Great & Lesser Tubercles and the Deltoid Tuberosity
  3. Forearm muscles attach to Medial & Lateral Epicondyles


Carpal Bones

The Carpal Bones has a total of 8 Bones. It has (2) two rows containing 4 bones each. Proximal is the First Row, and Distal the Second row:


  1. Pisiform
  2. Lunate
  3. Scaphoid
  4. Triquetrum


  1. Hamate
  2. Capitate
  3. Trapezoid
  4. Trapezium



Metacarpals are bones of the palm



Phalanges are bones of the fingers

  1. Thumb has Proximal & Distal Phalanx

  2. Fingers have Proximal, Middle & Distal Phalanx



The Femur is the Largest and Heaviest bone in the body.

  1. Head of the Femur, Articulates with the Acetabulum of the Pelvis
  2. The Hole in the Head of Femur is called Fovea Capitis
  3. Great & Lesser Trochanters are for Muscle attachment
  4. Medial & Lateral Condyles are found Distally



Patella is your Knee-Cup and is Triangular Sesamoid Bone (Sesamoid - is found in ligaments and tendons)




The Tibia is thick, strong weight-bearing bone on medial side of leg:

  1. It has 2 Flat Articular Surfaces (Medial & Lateral Condyles)
  2. The Tibial Tuberosity is a roughened anterior surface below the Patella
  3. The Distal Expansion is the Medial Malleolus



The Fibula is a slender Lateral Strut that helps stabilize the Ankle:

  1. The Fibula does not bear any of the body's weight
  2. Its joined to Tibia by Interosseous Membrame
  3. The Lateral Malleous is Distal Expansion