class of northwest institute of health sciences of 2nd batch, 1st semister

1. BONE & CARTILAGE
DR. SADAF AZIZ
LECTURER, NORTHWEST COLLEGE OF PHYSICAL THERAPY

2. TODAY’S LECTURE
• Surface marking of bone
• Cartilage
• Development of cartilage
• Microscopic picture of cartilage

3. SURFACE MARKING OF BONE

4. MARKING DESCRIPTION EXAMPLE
DEPRESSIONS & OPENINGS: SITES ALLOWING THE PASSAGE OF SOFT TISSUE OR FORMATION OF JOINT
1. FISSURE Narrow slit between adjacent parts
of bones through which blood vessels
or nerves pass
Superior orbital fissure of sphenoid
bone
2. FORAMEN (=hole) Opening through which blood vessels,
nerves, ligaments pass
Optic foramen of sphenoid bone
3. FOSSA (=trench) Shallow depression Coronoid fossa of humerus
4. SULCUS (=groove) Furrow along bone surface that
accommodates blood vessel, nerve or
tendon
Inter-tubercular sulcus of humerus
5. MEATUS (=passageway) Tube-like opening External auditory meatus of temporal
bone

6. MARKING DESCRIPTION EXAMPLE
PROCESSES: PROJECTIONS OR OUTGROWTHS ON BONE THAT FORM JOINTS OR ATTACHMENT POINTS FOR
CONNECTIVE TISSE (LIGAMENTS & TENDONS)
Processes That Form Joints
1. CONDYLE (=knuckle) Large rounded protuberance with a
smooth articular surface at end of
bone
Lateral condyle of femur
2. FACET Smooth, flat, slightly concave or
convex articular surface
Superior articular facet of vertebrae
3. HEAD Usually rounded articular projection
supported on neck of bone
Head of femur

8. MARKING DESCRIPTION EXAMPLE
Processes That Form Attachment Points For Connective Tissue
1. CREST Prominent ridge or elongated
projection
Iliac crest of hip bone
2. EPICONDYLE (epi=above) Typically roughened projection above
condyle
Medial epicondyle of femur
3. LINE (linea) Long narrow ridge or border Linea aspera of femur
4. SPINOUS PROCESS Sharp slender projection Spinous process of vertebrae
5. TROCHANTER Very large projection Greater trochanter of femur
6. TUBERCLE Variably sized rounded projection Greater tubercle of humerus
7. TUBEROSITY Variably sized rounded projection
that has a rough, bumpy surface
Ischial tuberosity of hip bone

10. CARTILAGE

11. DEFINITION
• Cartilage is a connective tissue
• It is composed of cells (chondrocytes) and fibers (collagen or
yellow elastic) embedded in a firm, gel-like matrix
• It is much more elastic than bone.

13. GENERAL FEATURES
• Cartilage has no blood vessels or lymphatics. The nutrition of cell
diffuses through the matrix
• Cartilage has no nerves. It is therefore insensitive
• Cartilage is surrounded by a fibrous membrane called
perichondrium, which is similar to periosteum in structure and
function. The articular cartilage has no perichondrium, so that its
regeneration after injury is inadequate
• When cartilage calcifies, the chondrocytes die and the cartilage is
replaced by bone like tissue

15. TYPES OF CARTILAGE
HYALINE CARTILAGE FIBROCARTILAGE ELASTIC CARTILAGE
LOCATION In the articular cartilages
of long bones, sternum,
ribs, nasal and laryngeal
cartilages
In the intervertebral disc
of pubic symphysis, TMJ,
sterno-clavicular joint
In the pinna, EAM,
Eustachian tubes,
epiglottis,
COLOUR Bluish white Glistening white yellowish
APPEARANCE Shiny/ translucent opaque opaque
FIBERS Very thin Numerous white fibers
(collagen fibers)
Numerous yellow fibers
(elastic fibers)
ELASTICITY Flexible. Great resistance
to wear.
More firm strongest Most flexible
REPAIR Cannot repair itself Cannot repair itself Repairs itself

17. STRUCTURE OF CARTILAGE
• A typical piece of cartilage in the skeleton is composed of cartilage
tissue which contains no nerves or blood vessels.
• It is composed of cells (chondrocytes) and fibers (collagen or yellow
elastic) embedded in a firm, gel-like matrix which is rich in
mucopolysaccaride
• The cartilage is surrounded by a layer of dense connective tissue, the
perichondrium (“around the cartilage”)
• This strong layer acts like a girdle to resist outward expansion when the
cartilage is subjected to pressure.
• The perichondrium also functions in the growth and repair of cartilage.
• Cartilage tissue consists primarily of water and is very resilient (the
ability to spring back to the original shape after being compressed.

19. DEVELOPMENT OF CARTILAGE
DEVELOPMENT OF CARTILAGE MODEL
• Specific chemical messages cause the mesenchymal cells to crowd
together in the general shape of future cartilage, and then into
chondroblasts.
• The chondroblasts secrete cartilage cartilage extracellular matrix,
producing a cartilage model consisting of hyaline cartilage. A
covering called the perichondrium develops around the cartilage
model.

23. GROWTH OF CARTILAGE MODEL
• Once chondroblasts become deeply buried in the cartilage
extracellular matrix, they are called chondrocytes.
• The cartilage model grows in length by interstitial growth.

24. GROWTH OF CARTILAGE
1. APPOSITIONAL GROWTH:
• Growth from outside, the chondroblasts (cartilage forming cells)
in the surrounding perichondrium produce the new cartilage tissue
2. INTERSTITIAL GROWTH:
• Growth from within, chondrocytes within the cartilage divide and
secrete new matrix.
• Cartilage stops growing in the late teens when the skeleton itself
stops growing and chondrocytes don not divide again.

26. THE END….!!!