Post on 15-Jan-2016
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
– 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
– 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
• 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
Other skull bones
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
– 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– 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:
– 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