unit 2 skeletal system 2 joints

In joints, stability and mobility are related. As stability of a joint decreases, mobility

increases

Joints can be classified based on __, which is determined by the degree of movement at the joint.

function

Joints can be classified based on __, which includes the connective tissues that hold the bones together and whether a joint cavity is present.

structure

This is a place where a bone contacts another bone. These are also called joints.

articulation

In joints, stability and mobility are related. As stability of a joint increases, mobility

decreases

These are immovable joints.

synarthroses

In this type of joint, the bones are joined by fibrous tissue.

fibrous joints

In this type of joint, a joint cavity is present.

synovial joints

These are fully movable joints.

diarthroses

These are slightly movable joints.

amphiarthroses

In this type of joint, the bones are joined by cartilage.

cartilaginous joints

Fibrous joints in which articulating bones are joined by long strands of dense regular connective tissue are called

syndesmoses

Fibrous joints in which teeth are held into sockets by a fibrous ligament are called

gomphoses

Fibrous joints that bind skull bones together are called __.

sutures

If the articulating bones are joined by a fibrocartilage pad, the joints are called __.  Intervertebral joints and the joint between the two coxal bones are examples of this type of joint.

symphyses

If joints have joint cavities, the joints are classified as __joints.

synovial

Cartilaginous joints in which bones are joined by hyaline cartilage are called __. Epiphyseal plates and the joints between true ribs and costal cartilage are examples of this type of joint.

synchondroses

In a joint with a joint cavity, the bones are lubricated by a fluid called the

synovial fluid

The fluid inside synovial joints is secreted by the

synovial membrane

In a joint with a joint cavity, articulating surfaces of the bones are covered with a thin layer of hyaline cartilage, called the

articular cartilage

Periodontal membranes are found in which type of joints?

gomphoses

Identify the structure labeled “A” in the typical synovial joint diagram below.

Synovial cavity filled with synovial fluid

Identify the structure labeled “C” in the typical synovial joint diagram below.

Articular cartilage

Identify the structure labeled “B” in the typical synovial joint diagram below.

Articular capsule

In this type of synovial joint, the rounded head of bone #1 fits into a cuplike depression of bone #2

ball-and-socket joint

In this type of synovial joint, an oval articular surface of bone #1 fits into an oval depression of bone #2.

condylar joint

In this type of synovial joint, bone #1 has a rounded end which fits into a ring (or sleeve) made partly of ligament and partly of bone.

pivot joint

In this type of synovial joint, each articular surface has a concave area and a convex area. The concave area of 1 bone fits into the convex surface of the other bone.

saddle joint

In this type of synovial joint, the articular surfaces of both bones are flat.

plane joint

In this type of synovial joint, the cylindrical end of bone #1 fits into a trough-shaped surface of bone #2.

hinge joint

The joint between the trapezium and the first metacarpal is an example of this type of synovial joint.

saddle joint

Intercarpal joints, joints between carpals are examples of this type of synovial joint.

plane joint

Joints between metacarpals and phalanges (fingers 2-5) are examples of this type of synovial joint.

condyloid joint

The hip joint or shoulder joint is an example of this type of synovial joint.

ball-and-socket joint

The elbow joint or knee joint is an example of this type of synovial joint.

hinge joint

The proximal joint between the radius and the ulna or the joint between the atlas and axis is an example of this type of synovial joint.

pivot joint

A circular movement is called __. This is a sequence of movements in which the proximal end of an appendage remains relatively stable while the distal end makes a circular motion.

circumduction

This movement returns a body part that has been moved laterally to the midline.

adduction

A pivoting movement called __ occurs when a bone turns on its longitudinal axis. The movement forms an arc but does not form a complete circle.

rotation

This is movement that decreases the angle between two bones in an anterior-posterior plane.

flexion

This is the lateral movement of a body part away from the midline of the body.

abduction

This is movement that increases the angle between two articulating bones in an anterior-posterior plane.

extension

This is an extension movement at the ankle that moves the toes away from the dorsal surface of the leg. If you were standing on your toes with your heels raised so you could reach something on a high shelf, you would be in this position.

plantar flexion

This is a movement at the ankle that moves the toes upwards towards the dorsal surface of the leg. This is technically flexion of the ankle, even though it is called by a slightly different name.

dorsiflexion

This is a rotational movement that turns the forearm so that the palm faces posteriorly or inferiorly.

pronation

This is a rotational movement that turns the forearm so that the palm faces anteriorly or superiorly.

supination