Synovial Joint

Definition

It is joint which is covered by a membrane called synovium. It has good mobility.

e.g. shoulder joint, elbow joint, hip joint, knee joint

Characteristics

Hyaline cartilage

The articulating surfaces are covered by hyaline cartilages

The cartilages have smooth surfaces, strength to bear weight

Synovium :

Covers the parts inside the joint which are not covered by the cartilage. Lines the inner surface of the capsule

Secretes a viscous fluid : synovial fluid - lubricates, carries nutrition, helps stability through surface tension, carries phagocytes

Capsule

A strong fibrous tissue covering the synovial joint

Helps to hold the bones together

Loose enough to allow movements

Ligaments

Are strong fibrous bands which bind the bones together.

Situated outside the capsule

Tendons

Muscles and tendons surround the joint and act to move the bones of the joint

Bursae

Sacs which are situated around joints which are superficial; contain thin lubricating fluid; prevent friction between moving tendons, bones and muscles, skin

Movements

Flexion

Extension

Adduction

Abduction

Rotation

Inversion

Eversion

Circumduction