The Skeletal System

Axial skeleton Skull Vertebral column Rib cage Ribs Sternum

Skull: cranium + face Cranial bones: Frontal Parietal Temporal Occipital Sphenoid Ethmoid

Frontal bone Parietal bone Occipital bone Foramen magnum Occipital condyle

Temporal bone Squama temporalis Mastoid part Petrous bone Zygomatic proces Mandibular fossa Mastoid part Mastoid process Petrous bone Contains the middle/inner ear structures Tympanic part External acoustic meatus Styloid process

Sphenoid Base of the cranium Body Greater and lesser wings Sinuses Sella turcica Pterygoid processes Greater and lesser wings Many foramen Optic canal Superior orbital fissure Foramen ovale Foramen lacerum Foramen rotundum

Ethmoid Back and upper nose Perpendicular plate Ethmoid sinuses Crista gali Cribriform plate and foramina Superior and middle nasal conchae

Facial bones Maxilla Palatine bones Zygomatic bones Lacrimal bones Nasal bones Inferior nasal concha Vomer Mandible

Maxilla Palatine bones Alveolar processes Palatine process

Zygomatic and lacrimal bones Zygomatic bone zygomatic arch Lower ocular orbit Lacrimal bones nasolacrimal canal

Nasal bone, Vomer and Inferior nasal conchae

Other skull bones Hyoid bone

Other skull bones Auditory ossicles Three of the smallest bones in your body Middle ear cavity of the petrous part of the temporal bone (paired or unpaired?) From lateral – medial Malleus, incus & stapes

Bones with sinuses Frontal Maxillary Sphenoid Ethmoid Sinus: cavity with the bone of the skull  make it lighter + resonance box for the voice

Bones forming the orbit of the eye Frontal bone Zygomatic Maxilla Lacrimal Sphenoid Ethmoid

Bones forming the nasal cavity Ethmoid Vomer Palatine Maxilla Nasal bone Inferior nasal conchae

Various “hardcore” bones Remember that many of the cranial & facial bones are “paired” Paired = left & right Left & right parietal bones Left & right temporal bones Left & right lacrimal bones Nasal bones Zygomatic bones Maxilla bones Palatine bones Inferior nasal concha

Various “hardcore” bones Remember that many of the cranial & facial bones are “paired” UN-paired (single) Frontal bone Occipital bone Sphenoid bone Ethmoid bone Vomer bone Mandible Hyoid bone

Skull foramen http://www.studystack.com/studytable-2333

Vertebral column 31 vertebra divided into regions Forming various curves Cervical Thoracic Lumbar Pelvic

Typical vertebra Vertebral body : support Vertebral canal (foramen): for spinal cord Processes: for muscle attachment Spinous process Transverse processes Superior articular process Inferior articular process Facet: articulation with other vertebrae and ribs

Intervertebral foramen: formed by 2 adjacent vertebra  spinal nerves exit through it Intervertebral discs: made of an envelope of fibrocartilagenous tissues (interanulus fibrosus) and in the center of a gelatinous substance (nucleus pulposus)

What happens when a disc ruptures?

7 Cervical vertebrae Typical features: Small body Bifid spinous process Transverse foramen Special vertebrae: Atlas and Axis: Atlas = C1 round, occipital condyles Axis: Dens of axis C7: longer spinous process prominence

Note C7: prominent vertebra (landmark on the vertebral column

12 Thoracic vertebrae NO transverse foramen Body larger then cervical vertebra Spinous processes longer, tend to slent downward Facets of articulation with ribs

5 Lumbar vertebrae Large wide body Short spinous prcesses

5 sacral vertebrae  sacrum 5 sacral vertebrae fuse to form the sacrum Features: Auricular surface Median sacral crest Sacral canal Sacral foramina Apex Sacral promontory Coccyx 4 fused vertebrae  tailbone

Sternum - Ribs - 7 pairs true ribs - 3 pairs – false ribs - 2 pairs – floating ribs

Appendicular skeleton: upper extremity Pectoral girdle: Scapula Clavicle Upper arm: Humerus Lower arm: Ulna Radius Wrist: Matacarpals bones Hand Metacarpals Phalanges

Pectoral girdle Scapula Clavicle Left or right? The smooth side (subscapular fossa) is against the rib cage The glenoid fossa is lateral (it is where the humerus attaches) Clavicle Left or right: Sternal end (square end) against sternum, acromial end (flatter end) against acromiom

Clavicle Humerus The curvature near the sternal end sticks out See previous drawing Humerus Left or right? The head of the humerus must face medially The olecranon fossa (the largest fossa at the elbow) is posterior

Wrist and Hand See book

Appendicular skeleton: lower extremity Pelvic girdle Coxal bones Thigh Femur Lower leg: Tibia Fibula Ankle Tarsal bones Foot Metatarsal Phalanges

Coxal bone Left or right? The acetabulum must face externally The symphysis pubis is anterior

Femur Left or right? The head of the femur must face internally The smooth surface in the lower femur is anterior while the deep groove is posterior

Tibia - Fibula Tibia: Fibula: Left or right? The styloid process, at the base is the exernal malleolus or internal ankle The tibial tuberosity is anterior Fibula: The hed of the fibula is against the lateral condyle The styloid process is the lateral malleolus or external ankle Slented side of styloid process is posterior

Ankle - Foot

Scoliosis

Lordosis Kyphosis

Kyphosis