Transcript OSTEOLOGY

OSTEOLOGY
Bone-a-fide
THE BARE BONES OF IT
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STRUCTURE
FUNCTION
TYPES
IDENTIFICATION
GROWTH, DEVELOPMENT & HEALING
THE BONE CELL
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The osteocyte is surrounded by matrix
35% protein collagen for hardness and flexibility
65% mineral salts – mostly Calcium and
Phosphorus
Precursor – cells that manufacture the bone cells
– Osteoblasts
Cells that erode the bone matrix – Osteoclasts –
these constantly remodel the bones according to
the force of muscles.
Outer covering is a thin membrane called
Periosteum - encloses the bone - fibrous
connective tissue - contains blood vessels
OSSEOUS/BONY TISSUE
COMPACT BONE
 Usually found on the
outside where there is
more stress
 They are parallel
cylinders called
Osteons, which are
concentric tubes of
matrix, with a central
canal that carries
blood vessels.
 Tiny spaces within this
contain isolated
osteocytes
SPONGY or
CANCELLOUS bone
 It has a honeycomb
structure and bony
struts with spaces
called trabeculae
 Jelly like yellow
marrow that stores fat
 Red marrow that
produces blood cells
OSSIFICATION
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In embryonic development the bones
arise from the mesoderm.
They are usually either Fibrous
connective tissue or Cartilage.
The fibrous tissue ossification is
called INTRAMEMBRANOUS
The cartilaginous ossification is called
ENDOCHONDRAL.
Bone Ossification
Skeleton begins as cartilage in prenatal development
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At fetal age 2 months: - osteoblasts begin to deposit calcium
(ossification) - first begins in the center of the long bones - called
primary ossification points - ossification extends along the shaft at birth, shaft is fully ossified
 Postnatal bone growth occurs at secondary ossification points called "epiphyseal plates" or "growth plates"
The epiphyseal plate has four layers :
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1) Zone of resting cells - serves as reservoir for future growth
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2) Proliferative zone - cartilage cells increase in size
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3) Hypertrophic zone - cartilage cells arrange themselves in
vertical columns
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4) Calcified cartilage zone - cartilage cells erode and bone is
deposited by osteoblasts
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Ossification of short bones ossify from the center outward At birth,
about 400 ossification centers exist. After birth, another 400 more
develop. After puberty, growth plates ossify and bone stops
growth –there is evidence that excessive stress can cause
premature ossification.
Bone is constantly being broken down (osteoclasts) - rebuilt again by
osteoblasts - else, we could not recover from a broken bone.
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GROWTH PATTERN OF BONES
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GROWTH – our bones are growing all
the time. Maximum growth happens
within 18 yrs. Then mainly
reshuffling esp of face, vertebrae,
ribs and hips.
LONG bones grow most and skull
bones least.
Growth in long bones takes place at
the Epiphysis, at the ends.
FUNCTION
Strong, lightweight frame work, dynamic
and flexible.
 SUPPORT
 SHAPING BODY
 ANCHORAGE OF SKELETAL MUSCLES
 SURROUNDS AND PROTECTS INTERNAL
ORGANS
 MOVEMENT
 STORES FAT
 PRODUCES Red Blood Cells
 STORES CALCIUM
THE TYPES OF BONES
TYPES
LONG
FLAT
SHORT
IRREGULAR
LONG BONES
LIMBS
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ACT as LEVERS – responsible for movement.
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Weight Bearing
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LENGTH IS MORE THAN WIDTH –
The Diaphysis or shaft is longer than the Epiphysis or end, which is
usually rounded and expanded.
Epiphysis - expanded portion at the end - made of spongy
bone mostly with compact bone at the end
Diaphysis - between the epiphysis's - made of compact bone
Medullary Cavity - cavity in center of the bone - contains the
yellow marrow
Articular Cartilage - connection between bones
SHORT BONES
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Cube like shape
Form connective bridge
Limited movement
Stability is essential- predominantly in hands in feet
Facilitate movement by elasticity, shock absorpbtion
The CARPALS & TARSALS
FLAT
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Usually thin,
flattened and
slightly curved
Mostly protective in
function
Includes
STERNUM, RIBS,
SCAPULAE &
CRANIAL bones
IRREGULAR
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Those that don’t
have a
symmetrical
shapes or those
which don’t fall into
any other category
Includes the
FACIAL bones,
PELVIS &
VERTEBRAE
IDENTIFICATION
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Bones are identified by shape, position in body,
function and in relation to its surrounding
structures.
WHY DO WE NEED TO KNOW THIS ?
When there is an injury/trauma to any bone
structure, we must know what else could have
been affected – muscle, ligament, tendon, artery,
vein or nerve. We need to assess short term and
long term damage along with choosing right
remedies to promote healing.
Specific bone diseases including Arthritis,
Rheumatism, etc
Also to predict healing patterns in case of
fracture.
HEALING
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Bones heal by producing extra osteocytes that
occupy deficient area.
Then the dead tissue trapped within is either
completely re-absorbed or turned into a fibrous
scar over which the bone unites.
Long bones require to be set if healing needs to
take place.
The ability to produce RBC is usually lost or
diminished in the area of the healing.
Remedies like Symphytum, Ruta, Calc Phos aid in
the healing by speeding up the process.
Complete immobility of the area is essential.
AXIAL SKELETON
It consists of The Skull – 22 bones – 8 Cranial and
14 Facial
The Vertebrae – 24
The Ribs – 12
The Sternum
THE SKULL
The skull has cavities –
CRANIAL , NASAL , ORBITAL, ear.
It also has foramina- for blood
vessels and nerves, the biggest
being foramen magnum – for the
spinal cord.
It develops intramembranously and
ossification is complete at 1.5 yrs
when the fontanells disappear.
Remedies for fontanelle ossification
– Calc Carb, Calc Phos, Sil
Bones of Face and Skull
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Bones not in diagram –
Ethmoid (behind nasal)
Lacrimal (part of orbit),
Palatine (rear of hard palate), inferior
nasal concha,
Vomer (nasal septum)
Other Facial Bones mandible
 hyoid bone
 Middle ear bones – malleus , incus stapes
The Vertebrae
This surrounds and protects the spinal
cord. The structure is a short pillar like
body – centrum with projections called
spinous and transverse processes, which
attach to ligaments and back muscles.
The body and the neural arch make the
vertebral foramen.
Between each vertebrea- are
intervertebral discs- cartilage pads with
jelly like filling.
Ribs and Sternum
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The ribs are attached to
vetrebrae at the back and to
cartilage in front, which is
then attached to the
sternum. They are called
costo-chondral cartilages.
The last 2 ribs are called
floating ribs as they are not
attached to anything in the
front.
The sternum is held up by
the cartilages, its ends are
attached to muscles of the
neck and abdomen.
Occasionally an extra
cervical rib is present,
hampering neck movement.
The sternum is fused from 3
parts (body, manubrium,
and xyphoid process)
APPENDICULAR SKELETON
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It consists of PECTORAL GIRDLE –SCAPULA +
CLAVICLE and the Upper Limbs
PELVIC GIRDLE – ILLIUM, Ischium,
Sacrum, Pubis and the Lower Limbs
THE PELVIS
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THE MALE
Thick and
heavy
Deep
Narrow and
deep
Heart shaped
Smaller
Narrow
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Round
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Large
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Structure
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P major
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Shallow
Wide and
shallow
Oval/round
Larger
Wide
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Oval
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Small
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P minor
P inlet
P outlet
-P arch +
suprapubic angle
-Obturator
Foramen
-Acetabulum
THE FEMALE
Thin and light
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The Hip Bones
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Illium
Ischium
Sacrum
Pubis
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LOWER LIMBS
THE FEMUR
Articulates with the
Illium via the obturator
foramen proximally and
to the Tibia and Patella
via the condyles distally
(at the bottom)
Most common injury is
fracture at the neck
which is mostly in the
elderly and a hip
replacement surgery is
performed where the
head is replaced.
If break anywhere else
– then usually
associated with major
muscle damage and
blood loss – which can
be fatal if the femoral
artery is cut.
TIBIA &
FIBULA
The head of the
fibula fits just under
the lateral condyle
of the Tibia.
The inner edges of
the distal ends of
the bones articulate
with each other,
The Tibia articulates
with the Femoral
condyles and
Patella proximallyforming the Knee Jt
and the Calcaneous
bone distally to
form the Ankle Jt.
THE PECTORAL GIRDLE
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THE SCAPULA
The Glenoid
fossa articulates
with the head
of the
Humerous
The Acromion
process
articulates with
the clavicle
absorbs shock
of shoulder
impact,
THE CLAVICLE
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Acromial end- is flat and has a small facet for articulation with
the acromion;
Sternal end- has a large facet for articulation with the
manubrium, and first costal cartilage;
Conoid tubercle- conoid ligament of the coracoclavicular
ligament attaches here;
Trapezoid line- trapezoid portion of the coracoclavicular
ligament attaches here.
THE HUMEROUS
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It is part of the
shoulder joint or
rotator cuff.
Attached by the head
to the scapula at the
proximal end and to
the Radius at the
Capitulum-head of
radius- and the Radial
fossa in flexion
Ulna- Coronoid fossa
in flexion and
Olecrenon fossa in
extension
Most common injury
to the bone is fracture
at the surgical neck.
RADIUS & ULNA
They are the most
commonly fractured bones.
Called Colles #,the other
being Barton’s #.
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The trochlear notch is
the point where the
humerous articulates with
the ulna and the radial
notch is the point where
the ulna articulates with
the head of the radius
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The styloid process of
the radius forms the
medial margin of the wrist
while the styloid process
of the ulna forms the
lateral margin of the wrist.
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The Hand
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Attachments – to
various muscles of the
forearm and ligaments
that hold all these
small bones together.
Carpals articulate with
metacarpals which in
turn articulate with
the fingers or
phalanges.
Special movement –
opposable thumb
Other movementsholding, tearing,
pincer action
The Foot
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Attachments – to
various muscles of
the ankle and
ligaments that hold
all these small bones
together.
Tarsals articulate
with metatarsals
which in turn
articulate with the
fingers or
phalangesproximal,
intermediate and
distal.
Special movementsbalance of entire
body weight across
the arch/bones
Stretch Up…
Dr Anjali Hariharan