8. Musculoskeletal System

Question 1

Types of joints (articulating bones)

Answer 1

Articulating bones- bones that meet and move at a joint

Question 2

Joints, joint types and articulating bones

Answer 2

Joint: elbow
Joint type: hinge
Articulating bones: radius, ulna, humerus

Joint:shoulder
Joint type: ball and socket
Articulating bones: scapula, humerus

Joint: hip
Joint type: ball and socket
Articulating bones: pelvis, femur

Joint: knee
Joint type: hinge
Articulating bones: femur, tibia

Joint: ankle
Joint type: hinge
Articulating bones: talus, tibia, fibula

Question 3

Agonist and antagonist

Answer 3

Joint action: elbow flexion
Agonist: biceps
Antagonist: triceps

Elbow extension
Triceps
Biceps

Ankle plantar flexion
Gastrocnemius
Tibialis anterior

Ankle dorsi flexion
Tibialis anterior
Gastrocnemius

Knee flexion
Hamstrings
Quads

Knee extension
Quads
Hamstrings

Hip flexion
Hip flexors
Gluteals

Hip extension/hypertension
Gluteals
Hip flexors

Hip adduction
Adductors
Gluteus medius/minimus

Hip abduction
Gluteus medius/minimus
Adductors

Hip horizontal adduction
Adductors/hip flexors
Gluteus medius/minimus

Hip horizontal abduction
Gluteus medius/minimus
Adductors/hip flexors

Shoulder flexion
Anterior deltoid
Latissimus dorsi

Shoulder extension/hyper extension
Lats
Anterior deltoid

Shoulder horizontal abduction
Lats
Pecs

Shoulder horizontal adduction
Pecs
Lats

Shoulder adduction
Lats
Middle deltoid

Shoulder abduction
Middle deltoid
Lats

Question 4

Types of muscle contraction

Concentric/eccentric) (isotonic/isometric

Answer 4

An isotonic contraction is where the muscles are contracting and changing length so that movement takes place. The two types are:
•concentric contraction: when the muscle short and under tension
•eccentric contraction:when the muscle lengthens under tension

An isometric contraction is where the muscle is under tension but there is no physical movement such as a bicep curl but holding the weight in place

An eccentric contraction is where the muscle is acting as a brake such as the lowering phase of a bicep curl. Muscles are capable of generating greater forces under eccentric conditions than under either isometric rule concentric contractions

Question 5

Planes and axis

Answer 5

Flexion, extension, plantar flexion, dorsi flexion and hyper extension occur in a sagittal plane about a transverse axis. A sagittal plane divides the body into right and left halves and a transverse axis runs from side to side across the body.

Horizontal abduction and horizontal adduction occur in a transverse plane about a longitudinal axis. A transverse plane divides the body into upper and lower halves and a longitudinal axis runs from top to bottom

Abduction and adduction occur in a frontal plane about a sagittal axis. A frontal plane divides the body into front and back halves and a sagittal axis runs from front to back