Question

What is synovial joint?

Answer 1

• Joints are essential for all types of movements involving the bony parts of the body and classified according to their degree of movement. Joints vary from immovable to freely movable.
• The three major structural forms are fibrous, cartilaginous and synovial joints.
• The bones of a synovial joint are joined (fastened and stabilized) by ligaments that form a capsule. Capsule is lined with synovial membrane, which secretes synovial fluid to lubricate and cushion the joint.

SYNOVIAL JOINT

• Synovial joints are most freely movable and flexible; contain a synovial fluid; helps in locomotion and allow for a variety of movement.
• Characterized by having a fluid filled synovial cavity between the articulating surfaces of the two bones.
• Synovial fluid is a complex mixture of polysaccharides, proteins, fats and cells, which forms a thin lubricating film covering the surfaces of a joint.
• Some of the EXAMPLES of synovial joints are as stated below:
  • Ball and socket joint (between humerus and pectoral girdle and between the femur and the coxal bone; forms hip and shoulder)
  • Hinge joint (knee joint; construct knee and elbow; permit movement in one direction only, like the hinges on a door)
  • Pivot joint (between atlas and axis)
  • Gliding joint (between the carpals; as in the wrist and the ankle) and
  • Saddle joint (between carpal and metacarpal of thumb)