cartilage & joints

Cartilage & Joints

By

Dr. Noura El Tahawy

Cartilage

-Hyaline cartilage

-Yellow Elastic cartilage

-White fibrocartilage

Types

Articular cartilage

1) Hyaline cartilage


Laryngeal cartilages

Costal Cartilages


2) White fibrocartilage

Intervertebral Disc

2) Yellow elastic

fibrocartilage:

Ear Pinna

Joints

ByDR. Noura El Tahawy

Definition of Joint

� A joint is the location at which two or more

bones articulate or make contact. Some joints

like those of the skull are fixed and have no

movement, some like those of the vertebrae

can move slightly and some are freely

moveable like the joints of the limbs.

Classification of joints

� 1. Fibrous joints.

� 2. Cartilaginous joints.

� 3. Synovial joints.

The three main types

of joints

Fibrous joints

� Fibrous joints connect bones without allowing any

movement. The bones of the skull and pelvis are held

together by fibrous joints. The union of the spinous

processes and vertebrae, joints between the teeth and

maxilla and mandible are the examples of fibrous

joints.

Fibrous joints

Cartilaginous joints

� Cartilaginous joints are joints in which the bones are

attached by cartilage. In this type of joint, there is a

pad of fibro cartilage between the ends of bones

which form joints, where only some movement is

required. Joints at the pubic symphysis, joint between

the manubrium sterni and body of the sternum and

joints between the vertebral bodies are the examples

of cartilaginous joint.

*It does not allow any

movement

* This type is

characterized by having a

plate of cartilage between

the epiphysis & diaphysis

of the same bone. It is not

a true permanent joint, but

it is a temporary plate of

hyaline cartilage which

disappears in adulthood by

ossification.

2- Cartilagenous Joints

1) PRIMARY CARTILAGINOUS JOINT (synchondrosis)

i.e. It is represented by the

epiphysial plate of cartilage

intervening between the

epiphysis and diaphysis of

long bones.

SECONDARY

CARTILAGINOUS

JOINT:

Structure of Intervertebral disc

SECONDARY CARTILAGINOUS JOINT:

Synovial Joints

Characteristics of synovial joint

1. The capsule The joint is enclosed and surrounded by fibrous tissue. This

keeps the bones together. The capsule is such, that, it protects the bones

and joint from injury and at the same time allows free movement.

2. Articular cartilage: hyaline cartilage lines the bones which form the joint

and which are in contact with each other. Hence, the articular surfaces are

smooth. The hyaline cartilage also bears the weight of the body. It reduces

friction of the joint..

3. Synovial membrane lines the capsule,

4. Synovial fluid is secreted by the synovial membrane into the joint cavity. It

provides nutrition to the structures within the joint cavity.

5. In addition to the capsule, the bones are also attached and held together by

strong-tough ligaments made of dense connective tissue. These

ligaments prevent dislocation during normal movement.

6. The articulating surfaces of adjacent bones are reciprocally shaped.

� Articular cartilage

� Synovial joint cavity

� Synovial membrane

� Synovial fluid

� Articular capsule

� Reinforcing ligaments

� Articular disc or

minscus

Diagram showing the main structures of the Synovial Joint

The main movement of the synovial joints are

--- flexion: bending forward.

--- extension : means straightening or bending backward

--- abduction :- moving away from the midline of the body .

--- adduction :- moving towards the midline of the body .

--- rotation :- moving round the long axis of bone .

--- pronation :- turning the palm of the hand down .

--- supination :- turning the palm of the hand up .

--- circumulation :- combination of flexion , extension,

abduction , adduction ,

--- inversion :- turning the sole of the foot inwards.

--- eversion :- turning the sole of the foot outwards .

Main synovial joints of the Upper

limb

Shoulder joint

� It is a ball and socket type of joint. The head of the humerus rotates within the glenoid

cavity of the scapula. It is also known as humero-scapular joint.

This joint is formed by

the lower end of the

humerus with the

upper ends of the

ulna and the radius. It

is a type of hinge

joint.

Elbow joint

� – proximal

(Superior) and

distal (Inferior)

joints

� The proximal

radioulnar joint is

formed by the rim of

the head of radius

rotating in the radial

notch of the ulna and

it has little movement.

The distal joint is

formed between the

distal end of the

radius and the head

of the ulna. It is a

pivot joint.

Radio-ulnar joints

Wrist joint

� This joint is formed by the distal end of the

radius and the proximal ends of the carpal

(wrist) bones. It is a condyloid joint.

Joints of wrist and fingers

� These are joints between the carpal bones, between carpal and metacarpal bones and between the metacarpal bones and proximal phalanges and between the phalanges. Intercarpal and carpal –metacarpal joints are gliding joints. Metacarpophalangeal joints are condyloid joints and interphalangeal joints are hinge joints.

Coronal section through a metacarpophalangeal joint, a synovial joint. The

collateral ligaments are thickenings of the joint capsule .

Joints of the Lower limb

Bones& Joints of the

lower limb

Hip joint

� The head of the femur bone fits into the cup-shaped acetabulum of the hip bone. It is a ball and socket type of joint.

Knee joint

It is formed by the two

condyles of the femur

with the condyles of

the tibia and the

posterior surface of

the patella. It is a type

of hinge joint.

Ankle joint

� This joint is formed by the

distal end of the tibia and

its medial malleolus, the

distal end of the fibula and

its lateral malleolus with

the talus. It is a form of

hinge joint.

Bones& Joints of

the foot

Joints of the foot and toes

� Joints are formed between the tarsal bones,

between the tarsal and the metatarsals,

between the metatarsal bones and the proximal

phalanges and between the phalanges. They

are all gliding type of joints.

Joints of the Vertebral Column

Thanks

You can download the lecture from:

http://www.slideshare.net/nmohmed

cartilage & joints

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