JointsBasics

TyPES OF JOINTS...❖ fibrous or fixed joints ❖Cartilaginous or slightly moveable joints ❖ Synovial or freely moveable joints

fibrous joints ➢ When no movement occurs between the

bones concerned, the joint is described as fibrous (or fixed or immovable ).

➢ The bones are held in place by fibrous connective tissue.

➢ It is very difficult to damage this type of joint.

CARTILAGINOUS JOINT...➢ Cartilaginous joints are held in place by

cartilage, which allows slight movement to occur.

➢ Examples include the junction at two pelvic bones, the joints between the ribs and the sternum.

SYNOVIAL JOINTS...➢ The amount of movement possible is limited

by ligaments, muscles, tendons and adjoining bones.

➢ These joints are also known as synovial joints

➢ They occur at the shoulder, elbow wrist, finger, hip, knee, ankle and toes.

TYPES OF SYNOVIAL JOINTS...★ Ball and socket joint ★ Hinge joint★ Pivot joint★ Gliding joints★ Saddle joints ★ Condyloid (or ellipsoid) joints

BALL AND SOCKET JOINT...❖ this joint forms when the spherical head of one

bone fits into a cup-like cavity of another. ➢ the head of the humerus fits into a

depression in the scapula ➢ The head of the femur articulates with the

pelvis.

Hinge Joint...❖ This joint allows movement in one plane only ❖ They form when the convex surface of one

bone fits into the concave surface of the other ➢ elbow and the knee➢ also occurs at the ankle and➢ between the bones of the finger

Pivot Joint...❖ This type of joint are formed when rounded, pointed or

conical end of one bone articulates with a ring, formed partly by bone and partly by ligament. ➢ The first vertebra, on which the head is balanced (the

atlas) The second vertebra (the axis) . This allows the head to rotate

➢ Between the ulna and the radius of the forearm, which allows the rotation of the hand.

Gliding joint...❖ Allow movement in any direction in side-to-side or back-

and-forth motion. ❖ Restricted only by the ligaments of bony processes

surrounding the joint.❖ Gliding joints are joined between

➢ Carpal bones➢ Tarsal bones➢ The sternum➢ Clavicle.

Saddle Joint...❖ The two bones forming the joint are saddle

shaped - that is concave in one direction and convex in the other.

❖ They fit together in such a way that they allow side to side and back and forth movements➢ This joint is only located where the thumb

joins the palm of the hand.

Condyloid Joints...❖Have one surface of the bone slightly concave

depression in another bone.➢ Such joints occur between radius and the

carpal bones, the metacarpals bones and the phalanges of the toes.

❖ They allow movement in two direction such as side to side and up and down

Types Of Movement At a Joint...➔ Flexion (bending)

◆ usually decreases the angle of articulating bones ◆ bending the knee or elbow

➔ Extension (straightening)◆ increases the angle of articulating bones ◆ straightening the arm or leg after flexion

➔ Abduction◆ Which is movement away from the midline body ◆ lifting the arm upwards and away from the body

➔ Adduction◆ Which is movement towards from the midline body◆ returning the arm after abduction

➔ Rotation◆ which is the movement of a bone around its long axis