SKELETAL SYSTEM

CHAPTER 7“Wisdom lies in taking everything

with good humor and a grain of salt.” George Santayana

FUNCTIONS OF BONES

SUPPORT PROTECTION MOVEMENT STORAGE BLOOD CELL FORMATION

CLASSIFICATIONS OF BONES

COMPACT – HARD & DENSE; LOOKS SMOOTH AND HOMOGENOUS• 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

RED: MAKE RBC; FOUND AT ENDS OF LONG BONES/ CENTER OF OTHERS

YELLOW: CENTRAL CAVITIES OF LONG BONES (MEDULLARY CAVITY): MADE OF FAT

DEVELOPMENT OF BONES

LONG BONES ARE CARTILAGE FLAT BONES – FIBROUS

MEMBRANES OSSIFY INTO BONES AS FETUS

DEVELOPS FONTANELS CLOSE EPIPHYSEAL PLATES FOR GROWTH

4 GROUPS BY SHAPE

LONG – LONGER THAN WIDE; MOSTLY COMPACT, ARMS & LEGS

SHORT – CUBOID; SPONGY BONE; WRIST, ANKLE, KNEE CAP

FLAT BONES- THIN, FLAT, USUALLY CURVED; SPONGY BONE; SKULL, RIBS & STERNUM

IRREGULAR – SPINAL COLUMN; HIPS

LONG BONE STRUCTURE

DIAPHYSIS- SHAFT OF BONE EPIPHYSIS – ENDS OF THE BONE EPIPHYSEAL PLATE – GROWTH AREA

OF THE BONE EPIPHYSEAL LINE – SOLID; REMNANT

OF PLATE AFTER PUBERTY

CONTINUED

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 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

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

OSTEOBLASTS – BONE FORMING CELLS (BUILD)

OSTEOBLASTS TRAPPED IN MATRIX BECOME MATURE OSTEOCYTES

OSTEOCLASTS – BONE REMOVERS (CRUNCHES)

BONES WIDEN AS ‘BLASTS BUILD BY THE PERI- OSTEUM AND ‘CLASTS CRUNCH NEXT TO THE MEDULLARY CANAL (CANAL GETS WIDER TOO)

AXIAL vs APPENDICULAR

AXIAL• SKULL

• RIBS

• SPINAL COLUMN

APPENDICULAR• ARMS AND LEGS

• HIPS AND SHOULDERS

• CLAVICLE & SCAPULAE

Functional terms

Distinguishing featuresProjections

HeadProcessCondyleCrestSpine

Depressions or holesForamenSinusFossaMeatus

Hannah Montana - bone dancehttp://www.youtube.com/watch?v=ZGdK4T7WUrA

SKULL

FRONTAL PARIETAL TEMPORAL OCCIPITAL SPENOID ETHMOID

FACIAL BONES

NASAL VOMER INFERIOR NASAL CONCHAE LACRIMAL MAXILLA MANDIBLE PALANTINE ZYGOMATIC

FRONTAL

SINGLE BONE (UNPAIRED) FORMS FOREHEAD FORMS ROOF OF EYE ORBITS ANTERIOR PART OF CRANIAL FLOOR CONTAINS FRONTAL SINUSES

PARIETAL

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

PAIRED FORMS SIDES AND LATERAL BASE

OF SKULL SHARP PROJECTIONS ON UNDER-

SIDE ARE STYLOID PROCESSES MANDIBULAR FOSSA – SITE OF

ARTICULATION WITH MANDIBLE HOLDS EXTERNAL ACOUSTIC

MEATUS

OCCIPITAL

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

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 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

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

CHEEKBONES FORM LATERAL WALL OF EYE ORBITS

LACRIMAL BONES –MEDIAL WALL OF ORBIT

HAS A GROOVE FOR PASSAGE OF TEARS

NASAL BONES

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 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

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

26 IRREGULAR BONES• 7 CERVICAL

• 12 THORACIC

• 5 LUMBAR

• SACRUM (5 FUSED BONES)

• COCCYX (4 FUSED BONES)

INTERVERTEBRAL DISCS

BETWEEN VERTEBRA MADE OF FIBROCARTILAGE CUSHION ABSORB SHOCKS ALLOW FLEXIBILITY HIGH WATER CONTENT; SPONGY;

COMPRESSABLE

VERTEBRAL STRUCTURE

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

ATLAS -1- NO BODY; ALLOWS ROCKING OF OCCIPITAL CONDYLES; NOD HEAD “YES”

AXIS -2 DENS PROJECTS UP, ALLOWS PIVOT OF HEAD FOR “NO”

ALL ARE SMALL, LIGHT; TRANSVERSE SPINES HAVE FORAMINA FOR VESSELS TO SUPPLY BLOOD TO THE HEAD

12 THORACIC

SPINOUS PROCESS ARCS DOWN TRANSVERSE SPINES ARTICULATE

WITH RIBS BODY IS LARGER THAN CERVICAL

VERTEBRAE’S BODY NO FORAMINA NOTED

5 LUMBAR

VERY DENSE BODIES SPINOUS PROCESSES ARE

SHORTER AND THICKER WEIGHT BEARING VERTEBRAE

SACRUM

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 VIEWSACRUM WITHFORAMINA

SACROILIALJUNCTION

COCCYX

STERNUM

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

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

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

HUMERUS FOREARM (ULNA & RADIUS) HAND

• CARPALS

• METACARPALS

• PHALANGES

BONES OF THE PELVIC GIRDLE

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

FEMUR PATELLA FIBULA/ TIBIA TALUS CALCANEUS TARSALS/ METATARSALS PHALANGES

DISORDERS OF THE BONES

METABOLIC: OSTEOPOROSIS; PAGET’S DISEASE; OSTEOMALACIA

TUMORS: OSTEOSARCOMA; CHONDROSARCOMAS

INFECTIONS: OSTEOMYELITIS; TUBERCULOSIS; POTTS DISEASE (TB IN THE SPINE)

STRUCTURAL DISORDERS

SCOLIOSIS KYPHOSIS LORDOSIS CLEFT PALATE FLATFOOT SPINA BIFIDA HERNIATED DISCS

HEALING BONE

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

Synarthroses – immovable joints Amphiarthroses – slightly moveable

joints Diarthroses – freely moveable joints

Structural Classification of Joints

Fibrous joints• Generally immovable

Cartilaginous joints• Immovable or slightly moveable

Synovial joints• Freely moveable

TYPES OF JOINTS

PLANE HINGE PIVOT CONDYLOID SADDLE BALL AND SOCKET

MOVEMENT AT SYNOVIAL JOINTS

FLEXION VS EXTENSION ABDUCTION VS ADDUCTION CIRCUMDUCTION ROTATION SUPINATION VS PRONATION INVERSION VS EVERSION DORSIFLEXION VS PLANTAR FLEXION

IMBALANCES OF JOINTS

ARTHRITIS OSTEOARTHRITIS RHEUMATOID ARTHRITIS GOUT IMBALANCE OF BONES

• OSTEOPENIA

• OSTEOPOROSIS