Chapter 8 - Articulations

Question 1

Synarthroses

Answer 1

Immovable joints

Question 2

Amphiarthroses

Answer 2

Slightly movable joints

Question 3

Diarthroses

Answer 3

Freely movable joints

Question 4

Fibrous Joints

Answer 4

Held together by tough fibrous non-elastic tissue. Lock a joint cavity and provide little or no movement. 3 types: sutures, syndesmoses, and gomphoses.

Question 5

Sutures

Answer 5

Found only in between membranous bones of the skull. Bones have irregular edges that interlock, leaving a small space which is filled by dense fibrous connective tissue. Allow for growth in youth.

Question 6

Syndesmoses

Answer 6

Bones are connected by a ligament with much longer fibers. The amount of movement varies with type and length of fiber.

Question 7

Gomphoses

Answer 7

A fibrous joint that connects the tooth to the bony alveolar sockets of the skull, and immovable joint.

Question 8

Cartilagenous Joints

Answer 8

Bones are connected by cartilage, no joint cavity, little mobility.

Question 9

Synchondroses

Answer 9

Bones are connected by hyaline cartilage. Almost always synarthrotic or amphiarthrotic. Ex: epiphyseal plate.

Question 10

Symphysis

Answer 10

Bones are joined by a pad of fibrocartilage. The articular surfaces are covered by articular (hyaline) cartilage. Joints are reinforced by ligaments which give them strength. Are slightly moveable, give cushioning from impact.

Question 11

Synovial Joints

Answer 11

Most widely distributed and most complex. Bones usually meet inside a fluid filled capsule

Question 12

Articular Capsule

Answer 12

Dense fibrous connective tissue continuous with the periosteum of bones. Reinforced by ligaments, it contains fluid, and physically holds the bones together.

Question 13

Articular Cartilage

Answer 13

A thin layer of hyaline or fibrocartilage. It covers the articular ends of the bone, it makes the ends very smooth which greatly reduces friction.

Question 14

Synovial Membrane

Answer 14

Lines the articular capsule, produces synovial fluid.

Question 15

Synovial Fluid

Answer 15

Slippery, viscous fluid. Consists of plasma and hyaluronic acid. If functions to protect, lubricate, and deliver nutrients.

Question 16

Synovial Bursae

Answer 16

Connective tissue flat sacs, lined by the synovial membrane. Usually found between muscles and tendons and bones that rub against each other. Main function is to reduce friction.

Question 17

Tendon Sheaths

Answer 17

Resemble a tubular, elongated synovial bursa. Wrap around large tendons that must move a long distance or that are under a large amount of pressure. They reduce friction.

Question 18

Capsular Ligaments

Answer 18

Intrinsic, found within a capusle

Question 19

Extracapsular Ligaments

Answer 19

Found outside of the capsule

Question 20

Intracapsular Ligaments

Answer 20

Deep, deep inside the capsule. Covered by synovial membrane.

Question 21

Factors Influencing Stability:

Articular Surfaces

Answer 21

Plays a minimal role, unless in a large socked.

Question 22

Factors Influencing Stability:

Ligaments

Answer 22

Help direct movement and prevent undesirable movement. Play a minimal role, but the more ligaments present, the more stabilizing.

Question 23

Factors Influencing Stability:

Muscle Tone

Answer 23

The major stabilizing factor. Very important in knee, shoulder, and arches of feet.

Question 24

Uniaxial Synovial Joint

Answer 24

Permit movement in one plane only. 2 basic types hinge and pivot joints

Question 25

Hinge Joints

Answer 25

Single transverse axis, like a door. Ex: elbow, knee, interphalangeal.

Question 26

Pivot Joints

Answer 26

Single axis, the long axis of the bones. Ed: Radioulnar joint.

Question 27

Biaxial Joints

Answer 27

Permit movement in two planes. 2 types condyloid and saddle

Question 28

Condyloid Joints

Answer 28

The articular surface of one bones is convex and the other is concave. Allow for angular movement. Ex: Metacarpophalangeal joints.

Question 29

Saddle Joints

Answer 29

Unique joint. Found in the carpal metacarpal joints of the thumb. The articular surface is saddle-shaped. Allows for opposable thumb.

Question 30

Multiaxial Joints

Answer 30

Universal joints, they permit movement in many planes. Only one type, ball and socket

Question 31

Ball & Socket Joints

Answer 31

One bone has a ball that fits into a cup shaped depression on the other bone. Ex: Hips and shoulders.

Question 32

Nonaxial Joints

Answer 32

One flat, or nearly flat, bone slipping over another. Permits a light sliding movement in several different directions.

Question 33

Angular Joints

Answer 33

Between two bones, it either increases or decreases the angle between the bones.

Question 34

Flexion

Answer 34

Decreasing the angle between two bones.

Question 35

Rotation

Answer 35

A turning movement

Question 36

Dorsiflexion

Answer 36

Flexion of the ankle

Question 37

Extension

Answer 37

Increasing the angle between two bones

Question 38

Supination

Answer 38

Rotation of the hand so that the palm is face up

Question 39

Pronation

Answer 39

Rotation of the hand so that the palm is face down

Question 40

Abduction

Answer 40

Movement away from the midline

Question 41

Adduction

Answer 41

Movement toward the midline

Question 42

Circumduction

Answer 42

Rotation of a limb so that a cone is circumscribed

Question 43

Inversion

Answer 43

Medial movement of the food

Question 44

Protraction

Answer 44

Thrusting the mandible forward

Question 45

Retraction

Answer 45

Moving the mandible backwards

Question 46

Elevation

Answer 46

Lifting a body part as the the jaw in chewing

Question 47

Depression

Answer 47

Lowering a body part as the jaw in chewing

Question 48

Opposition

Answer 48

Movement of the thumb to oppose the fingers

Question 49

Tempro-mandibular Joint

Answer 49

Has two joint cavities. Allows for typical hinge movement, opening and closing, and for protraction-retraction, and lateral movement.

Question 50

Elbow Joint

Answer 50

Joint forms a hinge with the humerus through the trochlea of the ulna. The radius pivots with the ulna. The radius isn't involved in the extension/flexion of the elbow, but rotates with a ligament to provide pronation/supination of the forearm.

Question 51

Hip Joint

Answer 51

The socket has an extremely deep socket and is reinforced by internal ligaments that connect the head of the femur to the os coxae. The joint is extremely strong, the strongest of the synovial joints.

Question 52

Knee Joint

Answer 52

Hinge joint with relatively flat articulating cartilages. Because of the flatness of the joining bones, the joint depends entirely upon ligaments to prevent lateral movement. It is the most vulnerable joint in the body as for as damage is concerned. The most complex joint in the body.

Question 53

Dislocation

Answer 53

Displacement of the articular surfaces. More common where the articular surfaces don't lock. Causes damage to the surrounding tissue.

Question 54

Sprain

Answer 54

Involved damaged ligaments. Either torn or stretched. Results from twisting. Because ligaments are poorly vascularized, they heal slowly. They may repair themselves, if not surgery is necessary.

Question 55

Cartilage Injuries

Answer 55

Most involve the knee menisci (semilunar cartilage) which are avascular and only rarely can repair themselves

Question 56

Rheumatoid Arthritis

Answer 56

Degenarition of joints resulting in the fusion of bones. Created a complete loss of mobility, usually affects people over 40. Inflammation of the synovial membrane forms a pannus that clings and destroys the cartilage, ossifiying fibrous tissue and causing crippling.

Question 57

Osteoarthritis

Answer 57

Most common, also degenerative, wear and tear on overworked joints. Related to aging. Treated by activity, pain medication, and glucosamine. More prominent in women than men.

Question 58

Arthritis

Answer 58

Degenerative disease which includes a number of different diseases all involving the inflammation of the joints, swelling, and painful movement of joint. More than 100 types.

Question 59

Gouty Arthritis

Answer 59

Uric acid builds up in the joints. Most common in men, typically the big toe.

Question 60

Lyme Disease

Answer 60

Bacteria transmitted by ticks that live on deer and mice. Flu-like symptoms, disorientation, joint pain, arthritis. Early on can be treated with antibiotics.

Question 61

Tendonitis

Answer 61

Inflammation of the tendon sheaths. Caused by overuse.

Question 62

Bursitis

Answer 62

Bursae become inflamed, swell and cause pain. Caused by excessive stress of friction.