Skeletal System

Skeleton System The skeletal system is broken into 2 categories Axial Skull Ribs Sternum Vertebral column Appendicular Upper extremity Lower extremity

Skull Made up 0f 22 bones 8 bones fused together make the cranium Frontal Parietal Temporal Occipital 14 bones make up the face Mandible Maxilla Zygomatic Nasal bones Only joint that moves in the skull is the temporomandibular joint mandible forms a hinge with temporal bone

Ribs Purpose of the ribs are to protect the heart and lungs There are 12 pairs of ribs 1-7: True ribs 8-12: False ribs 11-12: Floating ribs Sternum Also called the “breastbone” Sometimes used as a painful stimulus 3 parts Manubrium Articulates with clavicle Body Articulates with ribs 2-7 Xiphoid process Attachment for rectus abdominis Also a landmark for CPR

Vertebral Column Spinal Column or vertebral column stretches from the base of skull to coccyx Composed of bones called vertebrae Intervertebral disks separate body of each vertebrae Vertebrae has ligaments in front and back to help keep column together Each vertebrae has 3 parts Body Spinous Process Vertebral foramen Holds spinal cord

Sections of the Vertebral Column There are 5 sections to the vertebral column 7 Cervical vertebrae Smallest vertebra 12 Thoracic vertebrae Articulate with the ribs 5 Lumbar vertebrae Supports most of the body’s weight Sacrum Composed of 5 fused vertebrae Coccyx Composed 4 fused bones Also called the “tail bone”

Shoulder Girdle Consists of 2 bones Scapula Clavicle Also called the shoulder blade Free floating bone between ribs 2 & 7 posteriorly Clavicle Also called the collar bone Attaches to axial skeleton

Arm Humerus Forearm (2 bones) Long bone located in the upper arm Radius Lateral long bone in the forearm Ulna Medial long bone in the forearm

Hand There are 27 bones that make up the hand Carpals Metacarpals 8 small bones that make up the wrist Metacarpals 5 long bones that make up the palm Named according to their position in the hand Ex. 1st metacarpal is thumb, 5th is little finger Phalanges 14 bones that make up the fingers Also called digits Each finger has 3 bones Each thumb has 2

Pelvic Girdle Consists of 3 bones Attaches lower limb to axial skeleton Transmits weight of upper body to lower limb Supports pelvic bones 3 main bones Ilium Largest part of pelvic girdle Ischium Located posteriorly Called “sit bones” Pubis Located anteriorly Come together to form pelvis

Leg Consists of 4 bones Femur Patella Tibia Fibula Longest and strongest bone in the body Built for stability, not flexibility Patella Also called knee cap Tibia Long bone on the medial aspect of leg 90% weight bearing Fibula Long bone on the lateral aspect of leg 10% weight bearing

Foot Consists of 26 bones Tarsals Metatarsals Phalanges 7 bones that make up the ankle Metatarsals 5 long bones of the foot Name according to their position in the foot Phalanges 14 bones that make up phalanges Each toe contains 3 Each toe contains 2