Unit 2: Introduction to Joints and Muscles

Question 1

Flexion

Answer 1

Decreasing the angle between body parts

Question 2

Extension

Answer 2

Increasing the angle between body parts

Question 3

Internal Rotation

Answer 3

turning on an axis medially along the long axis of a bone

Question 4

External Rotation

Answer 4

turning outwardly or laterally along the long axis of a bone

Question 5

Abduction

Answer 5

moving away from the mid-line

Question 6

Adduction

Answer 6

moving toward the middle

Question 7

Eversion

Answer 7

moving the sole of the foot laterally or AWAY from the big toe and medial side of the foot.

Question 8

Inversion

Answer 8

(moving the sole of the foot TOWARD the medial border or big toe side of the foot)

Question 9

Supination

Answer 9

(rotating the forearm & hand laterally) extend you arm to the front with your palm facing toward the ceiling …the thumb is on the lateral side of the hand….this is supination

Question 10

Pronation

Answer 10

(rotating the forearm & hand medially) extend your arm to the front with your palm facing toward the floor…The thumb is on the medial side of the hand now ….this is pronation

Question 11

Retraction

Answer 11

drawing the shoulders posteriorly (or back toward the spine)

Question 12

Protraction

Answer 12

drawing the shoulders anteriorly (or forward toward the chest)

Question 13

Elevation

Answer 13

raising or moving a part superiorly (lifting the shoulders)

Question 14

Depression

Answer 14

lowering or moving a part inferiorly (dropping the shoulders)

Question 15

Circumduction

Answer 15

a circular movement that combines flexion/extension with abduction/adduction (circling the leg in the hip socket)

Question 16

Articulation

Answer 16

A place of union or junction between 2 or more bones or parts of bones of the skeleton (ex. ribs articulate with their corresponding vertebrae in the spine)

Question 17

Synovial membrane

Answer 17

The synovial membrane consists of vascular (blood) supply connective tissue that produces synovial fluid

Question 18

Synovial fluid

Answer 18

The lubricating substance produced by the synovial membrane in a synovial joint. The fluid lies in the joint cavity.(ex. is the knee is a synovial joint with synovial fluid)

Question 19

Connective tissue

Answer 19

The layers of soft tissue beneath the skin: dermis, subcutaneous, and fascia. These serve to support organs, nerves, and muscles in interconnected layers.

Question 20

Cartilage

Answer 20

A resilient, semi-rigid form of connective tissue; It forms parts of the skeleton where motion occurs. You have more cartilage when you are young, but it lessens with age.(ex. the tip of your nose is formed by resilient cartilage)

Question 21

Tendon

Answer 21

A fibrous cord or band that connects a muscle to a bone or other structure.

Question 22

Ligament

Answer 22

A band or sheet of fibrous tissue connecting 2 or more bones, cartilages, or other structures. Serves as a support or stability for a joint (static stabilizers)

Question 23

Bursa

Answer 23

A closed sac with a synovial-like membrane and containing fluid; A bursa is usually found in areas subject to friction, like over an exposed part or where a tendon passes over a bone. (ex. - trochanteric bursa at the hip.)

Question 24

How many ways are joints classified?

Answer 24

3- according to the type of material by which the bones are united

Question 25

Synovial Joints

Answer 25

This joint has an articular capsule that encloses a joint cavity. Each bone surface is covered with articular cartilage and there is synovial fluid contained inside the joint capsule. Examples of this are the knee and shoulder joints.

Question 26

Fibrous Joints

Answer 26

These joints are united by fibrous tissue. There is usually less motion at these joints. An example is the sutures of the skull or the interrosseus membrane in the forearm.

Question 27

Cartilagenous Joints

Answer 27

These joints are united by hyaline or fibrocartilage. These joints are usually present early in life to allow for bone growth. If the epiphyseal plate of these cartilaginous joints is damaged, growth in children or teens can be stunted. Some fibrocartilage joints persist in the adult. An example would be the fibrocartilage intervertebral disc in the spine that joins the vertebrae together or the symphysis pubis where the pubic bone joins at the base of the pelvis in the front.

Question 28

Ball & Socket Joints (Synovial)

Answer 28

Multiaxial joints that move in multiple planes and axes * Allow a lot of motion *One surface is spherical and moves within the socket of the other bone *Motion includes flexion/extension, abduction/adduction, medial/lateral rotation and circumduction Ex. - the hip joint

Question 29

Hinge Joints (Synovial)

Answer 29

Uniaxial movement in one plane around one axis. * Permits flexion / extension movement only * Strong ligaments protect these joints Ex. - The elbow joint

Question 30

Pivot Joints (Synovial)

Answer 30

Uniaxial joints allowing rotation | Ex. - rotation of the radius bone in the arm

Question 31

How many types of synovial joints are there? Name them.

Answer 31

1. Ball & Socket 2. Hinge 3. Pivot 4. Plane and Condyloid 5. Saddle

Question 32

Plane and Condyloid Joints (Synovial)

Answer 32

Plane- Permits gliding or sliding movements * Usually occurs in small joints * Uniaxial - allows movement in only one plane around one axis Ex.- acromioclavicular joint - between the scapula (shoulder blade) and the clavicle (collar bone) Condyloid Joints - Biaxial movement in 2 planes * the axes lie at right angles to each other Ex. - knuckle joints

Question 33

Saddle Joints (Synovial)

Answer 33

Biaxial movement in 2 planes * Surfaces that oppose are shaped like a saddle Ex. - Carpometacarpal joint at the base of the thumb

Question 34

When describing the shapes and contours of a bone, what is a fossa?

Answer 34

a cavity or depression in a bone

Question 35

When describing the shapes and contours of a bone, what is a groove?

Answer 35

a long narrow indentation

Question 36

When describing the shapes and contours of a bone, what is a foramen?

Answer 36

a hole

Question 37

Describe the following protrusions or "bumps" when describing the shapes and contours of a bone. - Condyle - Crest - Head - Process

Answer 37

1. Condyle - a large segment of bone usually at the end; a site for articulation of a joint. 2. Crest - a ridge or border of bone 3. Head - a spherical shape usually at the end of a bone 4. Process - an "extension" of bone

Question 38

Whats the difference between a Trochanter, Tubercle, and a Tuberosity?

Answer 38

Trochanter - a large protrusion of bone Tubercle - a small protrusion of bone Tuberosity - a medium protrusion of bone

Question 39

What is the difference between an "Origin" and an "Insertion" in reference to muscles?

Answer 39

Origin- the site of the attachment of a muscle to a bone that is a fixed point. Insertion - the site of the attachment of a muscle to a bone that is a mobile point.

Question 40

Isometric contraction

Answer 40

a static contraction where there is no movement between the origin and insertion. There is force produced in the muscle, but no joint motion.

Question 41

Isotonic contraction

Answer 41

a dynamic contraction of the muscle where the relationship between the origin and insertion changes as the joint moves.

Question 42

Concentric contraction

Answer 42

a "shortening" contraction where the insertion is moving toward the origin. Example: at the elbow, the biceps insertion moves towards the origin as the muscle contracts to bend the elbow.

Question 43

Eccentric contraction

Answer 43

a "lengthening" contraction where the origin and insertion are moving away from each other. This type of contraction is usually a "braking" type of movement against gravity. Example: At the elbow, the biceps eccentrically contracts when the insertion moves away from the origin as the arm is straightening. This allows for control of motion into elbow extension, so the arm does not just drop.

Question 44

What are the there types of contractions that are possible in opposing gravity?

Answer 44

Shortening, Static, and Lengthening

Question 45

Shortening contraction

Answer 45

an example would be the abdominal muscles are shortening their muscle length to pull the torso forward against gravity.

Question 46

Static Contraction

Answer 46

An example is bending over an touching your toes. the muscle is neither lengthening or shortening as it works to hold a position statically. If the positions were "held", they would be considered static.

Question 47

Lengthening Contraction

Answer 47

An example would be the action of bending over to touch your toes. the back extensors are allowing the descent of the body forward while resisting the pull of gravity. These muscles are lengthening while they exert control over the forward bend.

Question 48

Prime movers (Agonists)

Answer 48

are the main muscles that activate a specific movement of the body. They contract actively to produce the desired movement.

Question 49

Antagonistic muscles

Answer 49

muscles that oppose the action of prime movers; as a prime mover contracts, the antagonist progressively relaxes, producing a smooth movement.

Question 50

Synergist

Answer 50

a muscle or group of muscles which cooperate to produce the same action. They may complement the action of the prime mover

Question 51

Fixator (Postural)

Answer 51

these muscles stabilize the most proximal parts of the body while movement is occurring more distally or laterally.

Question 52

What are the 4 principles of muscle use?

Answer 52

1. Muscles only pull, they do not push 2. Muscles contract in the center and pull equally on both ends 3. The action of a muscle on a joint will be determined by the attachments and path of the muscle. 4. Muscles must oppose gravity to produce a movement or maintain a position