SKELETAL SYSTEM
CHAPTER 7
“Wisdom lies in taking everything
with good humor and a grain of salt.”
George Santayana
FUNCTIONS OF BONES
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SUPPORT
PROTECTION
MOVEMENT
STORAGE
BLOOD CELL FORMATION
CLASSIFICATIONS OF BONES
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COMPACT – HARD & DENSE; LOOKS
SMOOTH AND HOMOGENOUS
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Haversian System; Volkmann Canals, Osteon (SEE
PAGE 130; EDITION 11)
SPONGY (CANCELLOUS)- SMALL THIN
PIECES OF BONE WITH OPEN SPACES;
AREA OF GROWTH AND RBC PRODUCTION
BONE MARROW
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RED: MAKE RBC; FOUND AT ENDS OF
LONG BONES/ CENTER OF OTHERS
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YELLOW: CENTRAL CAVITIES OF LONG
BONES (MEDULLARY CAVITY): MADE OF
FAT
DEVELOPMENT OF BONES
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LONG BONES ARE CARTILAGE
FLAT BONES – FIBROUS
MEMBRANES
OSSIFY INTO BONES AS FETUS
DEVELOPS
FONTANELS CLOSE
EPIPHYSEAL PLATES FOR GROWTH
4 GROUPS BY SHAPE
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LONG – LONGER THAN WIDE; MOSTLY
COMPACT, ARMS & LEGS
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SHORT – CUBOID; SPONGY BONE;
WRIST, ANKLE, KNEE CAP
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FLAT BONES- THIN, FLAT, USUALLY
CURVED; SPONGY BONE; SKULL, RIBS &
STERNUM
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IRREGULAR – SPINAL COLUMN; HIPS
LONG BONE STRUCTURE
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DIAPHYSIS- SHAFT OF BONE
EPIPHYSIS – ENDS OF THE BONE
EPIPHYSEAL PLATE – GROWTH AREA
OF THE BONE
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EPIPHYSEAL LINE – SOLID; REMNANT
OF PLATE AFTER PUBERTY
CONTINUED
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PERIOSTEUM – FIBROUS CONNECTIVE
MEMBRANE COVERING THE OUTER ASPECT
OF THE SHAFT
SHARPEY’S FIBERS – CONNECT THE
PERIOSTEUM TO THE BONE
ARTICULAR CARTILAGE – COVERS OUTER
ASPECT OF EPIPHYSES
MEDULLARY CAVITY – YELLOW MARROW
ENDOSTEUM - LINES MEDULLARY CANAL
BONE
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BONE MATRIX IS CALLED LACUNAE
OSTEOCYTES ARE FOUND IN SMALL
CAVITIES WITHIN THE LACUNAE
LACUNAE ARE ARRANGED IN A CIRCLE
CALLED LAMELLAE
A CANAL IN CENTER OF THE LAMELLAE IS
CALLED HAVERSIAN CANAL
OSTEON – CANAL & MATRIX RINGS
CONTINUED
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CANALICULI – RADIATING SMALL
CANALS FROM HAVERSIAN CANAL
TO ALL LACUNAE TO PROVIDE
NOURISHMENT
VOLKMANN’S CANALS RUN AT RIGHT
ANGLE TO HAVERSIAN CANAL
PROVIDING SPACE FOR THE BLOOD
VESSELS TO WEAVE THROUGH THE
COMPACT BONE
BONE FORMATION /
OSSIFICATION
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OSTEOBLASTS – BONE FORMING CELLS
(BUILD)
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OSTEOBLASTS TRAPPED IN MATRIX
BECOME MATURE OSTEOCYTES
OSTEOCLASTS – BONE REMOVERS
(CRUNCHES)
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BONES WIDEN AS ‘BLASTS BUILD BY THE
PERI- OSTEUM AND ‘CLASTS CRUNCH NEXT
TO THE MEDULLARY CANAL (CANAL GETS
WIDER TOO)
AXIAL vs APPENDICULAR
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AXIAL
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APPENDICULAR
• SKULL
• RIBS
• SPINAL COLUMN
• ARMS AND LEGS
• HIPS AND SHOULDERS
• CLAVICLE & SCAPULAE
Functional terms
Distinguishing features
Projections
Head
Process
Condyle
Crest
Spine
Depressions or holes
Foramen
Sinus
Fossa
Meatus
Hannah Montana - bone dance
http://www.youtube.com/watch?v=ZGdK4T7WUrA
SKULL
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FRONTAL
PARIETAL
TEMPORAL
OCCIPITAL
SPENOID
ETHMOID
FACIAL BONES
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NASAL
VOMER
INFERIOR NASAL CONCHAE
LACRIMAL
MAXILLA
MANDIBLE
PALANTINE
ZYGOMATIC
FRONTAL
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SINGLE BONE (UNPAIRED)
FORMS FOREHEAD
FORMS ROOF OF EYE ORBITS
ANTERIOR PART OF CRANIAL FLOOR
CONTAINS FRONTAL SINUSES
PARIETAL
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PAIRED
POSTERIOR TO FRONTAL BONE
FORMS SIDES & ROOF OF CRANIUM
BONES MEET AT MIDLINE TO FORM
SAGITAL SUTURE
MERGE LATERALLY WITH TEMPORAL
TO FORM SQUAMOUS SUTURE
POSTERIOR WITH OCCIPITAL TO
FORM LAMBDOID SUTURE
TEMPORAL
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PAIRED
FORMS SIDES AND LATERAL BASE
OF SKULL
SHARP PROJECTIONS ON UNDERSIDE ARE STYLOID PROCESSES
MANDIBULAR FOSSA – SITE OF
ARTICULATION WITH MANDIBLE
HOLDS EXTERNAL ACOUSTIC
MEATUS
OCCIPITAL
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FORMS BACK & POSTERIOR BASE OF
SKULL
BASE HAS FORAMEN MAGNUM
WHERE SPINAL CORD EXITS BRAIN
LATERAL TO FORAMEN ARE
OCCIPITAL CONDYLES WHERE SKULL
MEETS WITH FIRST VERTEBRA
ETHMOID
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FORMS ROOF OF NOSE AND MEDIAL
ASPECT OF EYE ORBITS
CRISTA GALLI PROJECTS BACK WHERE
DURA OF THE BRAIN ATTACHES
CRIBIFORM PLATE ALLOWS NERVES OUT
SUPERIOR & MIDDLE NOSE CONCHAE ARE
ANTERIOR EXTENSIONS IN THE LATERAL
WALLS OF NOSE – CAUSE TURBULENCE OF
AIR INHALED THROUGH NOSE
SPHENOID
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BUTTERFLY SHAPED
FORMS PART OF THE FLOOR OF CRANIAL
CAVITY BEHIND EYE
SMALL DEPRESSION (SELLA TURCICA)
HOLDS PITUITARY GLAND
FORAMEN OVALE ALLOWS NERVE TO EXIT
OPTIC CANAL & SUPERIOR ORBITAL
FISSURE ALLOW NERVES TO EXIT BRAIN
SPHENOID SINUSES – AIRY BONY AREAS
MAXILLAE
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PAIRED, FUSED TO FORM UPPER JAW
ALL FACIAL BONES ATTACH TO MAXILLA
• EXCEPT MANIBLE
2 PALANTINE BONE FUSE TO FORM HARD
PALATE IN ROOF OF MOUTH
2 SINUSES – DRAIN TO NASAL PASSAGE
• MUCUS LINED, CONTINUOUS TO THROAT
• INFECTION CAUSES SINUSITIS; PAIN IN UPPER
JAW OR THROAT
ZYGOMATIC
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CHEEKBONES
FORM LATERAL WALL OF EYE ORBITS
LACRIMAL BONES –MEDIAL WALL OF
ORBIT
HAS A GROOVE FOR PASSAGE OF
TEARS
NASAL BONES
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NASAL BONES ARE THE BRIDGE OF THE
NOSE
VOMER – FORMS THE NASAL SEPTUM
INFERIOR NASAL CONCHAE – THIN,
CURVED FROM LATERAL WALL; CAUSE
TURBULENCE OF THE AIR WE BREATHE
SO WE CAN HEAT & CLEAN IT
MANDIBLE
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LOWER JAW AND CHIN
LARGEST AND STRONGEST BONE IN FACE
JOINS AT TEMPORAL BONES TO MAKE
ONLY FREELY MOVING JOINT IN FACE
MANDIBLE RAMUS FORMS UPRIGHT
ANGLE TO TEMPORAL BONE
ALVEOLAR MARGIN HOLDS TEETH
HYOID BONE
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ONLY BONE IN BODY THAT DOES NOT
ARTICULATE WITH ANOTHER BONE
FOUND IN NECK
MOVEABLE BASE FOR THE TONGUE
ATTACHMENT POINT FOR NECK
MUSCLES THAT RAISE & LOWER LARYNX
FOR SPEAKING & SWALLOWING
VERTEBRAL COLUMN
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26 IRREGULAR BONES
• 7 CERVICAL
• 12 THORACIC
• 5 LUMBAR
• SACRUM (5 FUSED BONES)
• COCCYX (4 FUSED BONES)
INTERVERTEBRAL DISCS
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BETWEEN VERTEBRA
MADE OF FIBROCARTILAGE
CUSHION
ABSORB SHOCKS
ALLOW FLEXIBILITY
HIGH WATER CONTENT; SPONGY;
COMPRESSABLE
VERTEBRAL STRUCTURE
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BODY – BEARS WEIGHT; ANTERIOR
VERTEBRAL FORAMEN – OPENING
THROUGH WHICH THE SPINE PASSES
SPINOUS PROCESS – POSTERIOR
PROJECTION
TRANSVERSE PROCESSES -2 LATERAL
PROJECTIONS
VERTEBRAL ARCH
ARTICULAR PROCESSES
7 CERVICAL
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ATLAS -1- NO BODY; ALLOWS ROCKING OF
OCCIPITAL CONDYLES; NOD HEAD “YES”
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AXIS -2 DENS PROJECTS UP, ALLOWS
PIVOT OF HEAD FOR “NO”
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ALL ARE SMALL, LIGHT; TRANSVERSE
SPINES HAVE FORAMINA FOR
VESSELS TO SUPPLY BLOOD TO THE
HEAD
12 THORACIC
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SPINOUS PROCESS ARCS DOWN
TRANSVERSE SPINES ARTICULATE
WITH RIBS
BODY IS LARGER THAN CERVICAL
VERTEBRAE’S BODY
NO FORAMINA NOTED
5 LUMBAR
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VERY DENSE BODIES
SPINOUS PROCESSES ARE
SHORTER AND THICKER
WEIGHT BEARING VERTEBRAE
SACRUM
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SUPERIOR ARTICULATION WITH L5
INFERIOR WITH COCCYX
LATERALLY SACROILIAC JOINT
POSTERIOR ASPECT HAS MEDIAN SACRAL
CREST
SACRAL CANAL HOLDS END OF SPINE
POSTERIOR SACRAL FORMINA ALLOW
VESSELS TO PASS THROUGH SACRUM TO
LOWER EXTREMITIES
DORSAL VIEW
SACRUM WITH
FORAMINA
SACROILIAL
JUNCTION
COCCYX
STERNUM
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FLAT BONE
3 FUSED PARTS– MANUBRIUM,
BODY, & XIPHOID PROCESS
JUGULAR NOTCH – SUPERIOR
BORDER
STERNAL ANGLE- RIDGE WHERE
MANUBRIUM AND BODY FUSED
XIPHISTERNAL JOINT – AT 9TH
THORACIC VETEBRAL LEVEL
RIBS
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ARTICULATE WITH SPINE IN BACK,
ARC DOWNWARD IN FRONT, ATTACH
WITH HYALINE CARTILAGE IN FRONT
1ST 7 PAIRS – TRUE RIBS
NEXT 5- FALSE RIBS
LAST TWO PAIRS – FLOATING
INTERCOSTAL SPACES HAVE
MUSCLES, NERVE, & BLOOD VESSELS
APPENDICULAR SKELETON
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SHOULDER GIRDLE = CLAVICLE
ATTACHES TO SCAPULA LATERALLY
CLAVICLE – COLLAR BONE – HOLDS ARM
AWAY FROM THORAX; PREVENTS
SHOULDER DISLOCATION
SCAPULA – SHOULDER BLADE,
TRIANGULAR
BONES OF THE ARM
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HUMERUS
FOREARM (ULNA & RADIUS)
HAND
• CARPALS
• METACARPALS
• PHALANGES
BONES OF THE PELVIC GIRDLE
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COXAL BONES (HIP BONES)
ILIUM
ISCHIUM
PUBIS (MEET AT PUBIC SYMPHYSIS)
FALSE vs TRUE PELVIS
ANGLE OF PUBIC ARCH DENOTES
SEX OF PERSON
LOWER LIMBS
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FEMUR
PATELLA
FIBULA/ TIBIA
TALUS
CALCANEUS
TARSALS/ METATARSALS
PHALANGES
DISORDERS OF THE BONES
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METABOLIC: OSTEOPOROSIS; PAGET’S
DISEASE; OSTEOMALACIA
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TUMORS: OSTEOSARCOMA;
CHONDROSARCOMAS
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INFECTIONS: OSTEOMYELITIS;
TUBERCULOSIS; POTTS DISEASE (TB IN THE
SPINE)
STRUCTURAL DISORDERS
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SCOLIOSIS
KYPHOSIS
LORDOSIS
CLEFT PALATE
FLATFOOT
SPINA BIFIDA
HERNIATED DISCS
HEALING BONE
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HEMATOMA FORMATION
FIBROCARTILAGE CALLUS
(CARTILAGE MATRIX, BONY MATRIX
AND COLLAGEN) FORMS
BONY CALLUS – OSTEOBLASTS &
CLASTS ENTER AREA; CARTILAGE
BEGINS TO BE REPLACED BY BONE
REMODELING OCCURS (PATCH)
Functional Classification of
Joints
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Synarthroses – immovable joints
Amphiarthroses – slightly moveable
joints
Diarthroses – freely moveable joints
Structural Classification of
Joints
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Fibrous joints
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Cartilaginous joints
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Synovial joints
• Generally immovable
• Immovable or slightly moveable
• Freely moveable
TYPES OF JOINTS
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PLANE
HINGE
PIVOT
CONDYLOID
SADDLE
BALL AND SOCKET
MOVEMENT AT SYNOVIAL
JOINTS
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FLEXION VS EXTENSION
ABDUCTION VS ADDUCTION
CIRCUMDUCTION
ROTATION
SUPINATION VS PRONATION
INVERSION VS EVERSION
DORSIFLEXION VS PLANTAR FLEXION
IMBALANCES OF JOINTS
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ARTHRITIS
OSTEOARTHRITIS
RHEUMATOID ARTHRITIS
GOUT
IMBALANCE OF BONES
• OSTEOPENIA
• OSTEOPOROSIS