Bones Joints Access Human Biology Clare HargreavesNorris Introduction

Bones & Joints Access Human Biology. Clare Hargreaves-Norris

Introduction l l l Bones are connected to each other by connective tissue. A joint is where two or more bones meet together. Without joints the skeleton would not be able to move or have very limited movement. Clare Hargreaves-Norris

Cancellous (spongy) bone. Clare Hargreaves-Norris

Types of Joints. l l l There are three main types of joints. Immovable joints (fibrous or fixed): Fibrous connective tissue is used for immovable joints such is the cranium (sutures). Semi-movable joints (cartilaginous or slightly movable): Cartilage is used for semi-moveable joints such as the vertebrae. Synovial joints are the most common types of joints. Synovial joints are freely moveable joints that are held together by ligaments. Clare Hargreaves-Norris

Synovial joints l l l Synovial joints have a fibrous capsule that is lined with the synovial membrane. The synovial membrane secretes synovial fluid. Synovial fluid; – – l l l Lubricates the joint. Provides nutrients to joint. Helps to maintain stability of joint. Helps to keep ends of bones in line. Articular cartilage coats the ends of the bones to protect against wear and tear by reducing friction at the joint. Extra ligaments may surround the outside of the joint to provide extra strength and some also contain discs of cartilage to maintain stability. The main support to the joints is provided by muscles. Clare Hargreaves-Norris

Synovial Joints. l Synovial joints are subdivided according to movements possible. Clare Hargreaves-Norris

Ball and socket Location Movement l. The hip joint. l. Shoulder joints. ball and socket joint is one of the most mobile joints. l. It allows movement in three planes. Clare Hargreaves-Norris

The Three Planes of Movement. l l l Flexion (forwards and backwards). Extension (straightening). Abduction (away from body). Adduction (towards the body). Rotation (around). Circumduction (combination). Clare Hargreaves-Norris

Hinge joint Location Movement l. Elbow. l. The l. Phalanges fingers and toes. in hinge joint allows movement in one plane; l flexion. l extension. Clare Hargreaves-Norris

Pivot joint Location Movement l. Pivot l. The joints are located at the joint between the radius and ulna. l. In-between the atlas and axis at the base of the skull. pivot joint also allows movement in one plane; l rotation (round). l. Pronation (crossing over eg palm downwards). l. Supination (crossing over eg palm upwards). Clare Hargreaves-Norris

Saddle joint Location Movement l. The l. Saddle saddle joint is only found at the site where the carpal bone meets the metacarpal bone of the thumb. joint allows two planes of motion; l. Flexion. l. Extension. l. Abduction. l. Adduction. l. Small amount of rotation. Clare Hargreaves-Norris

Gliding joint Location Movement l. The l. Movement carpals of the hand, the tarsals of the feet are where gliding joints are found. at the gliding joint occurs as two flat surfaces slide over each other. l. In the hand, the carpals will slide over each to allow flexion, extension, and radial or ulnar deviation. l Likewise, in the foot, the tarsals slide over each other during pronation & supination. Clare Hargreaves-Norris

Condyloid joint Location Movement Knee joint. l Where the temporal and mandible bones meet. l. Allows l primary movement in mainly one plane; l - flexion and extension with small amounts rotation also. Clare Hargreaves-Norris