Lecture 8 - Muscles of the Appendicular Portion Flashcards
What is the primary function of the upper extremity?
movement
How is the scapula stabilized? Why does it need to be stabilized?
the scapula does not directly attach to the skeleton, the muscles act as antagonists to each other pulling in opposite directions to keep scapula immobile
What muscles are in the posterior group of the muscles that stabilize the scapula?
trapezius, rhomboid muscles, levator scapulae
What muscles are in the anterior group of muscles that stabilize the scapula?
pectoralis minor, serratus anterior
Describe the trapezius muscles
- large, flat, triangular
- extends from skull + vertebral column medically to the pectoral girdle laterally
- most superficial of back muscles
- for a diamond shape resembling a trapezoid
- functions: shrugging, pulling back the shoulders, extension of the head, when head is fixed stabilizes scapula
Describe the rhomboid mucles
- two muscles that are considered as one
- pulls the scapula towards the spine when pulling the shoulders backwards
Describe the Levator Scapulae
- part of the posterior group of muscles that stabilize the scapula
- extended from the cervical vertebrae to the scapula
- elevates the scapula
Describe pectoralis minor
- part of the anterior group of muscles
- extended from the coracoid process of the scapula to the upper ribs
- pulls the scapula anteriorly
- an auxiliary muscles for inspiration
Describe the serratus anterior
- part of the anterior group of muscles that stabilize the scapula
- antagonist to the rhomboid muscles
- auxiliary muscles for inspiration
What is the other name for the rotator cuff?
musculotendinous cuff
What is the rotator cuff
four muscles that pull the head of the numerous into the glenoid fossa during movements
What are the four muscles involved in the rotator cuff?
Supraspinatus: abound the sponge of the scapula
Infraspinatus: below the spine of the scapula
Teres Minor: teres= round, tubular, sausage-like
Subscapularis: occupies subscapular fossa
How is the rotator cuff formed?
the tendons of the SITS form a complete circle around the shoulder joint
Which muscles of the rotator cuff rotate the humerous?
infraspinatus, teres minor, subscapularis
What muscles of the rotator cuff DO NOT rotate the humerous?
Supraspinatus
Which of the rotator cuff muscles are an abuductor of the arm?
supraspinatus
What group of muscles work in conjunction with the rotator cuff muscles to produce movements of the arm?
movers of the shoulder joint
What group of muscles does the deltoid muscles belong to?
part of the movers of the shoulder joint
What are the movements of the deltoid muscles?
flexion/extension
medial/lateral rotation
-abduction of the arm
Describe the pectoralis major
- overlaps pectoralis minor
- produces movements of the humerous in the hugging action
- auxillary muscle for inspiration
- part of the movers of the shoulder joint
What muscle is the widest muscle in the back?
latissimus dorsi
What muscles produce movements of the humerous in the action of pulling something out of the back pocket?
latissimus dorsi and the teres major muscles
Describe the latissimus dorsi and teres major muscles
produce the movements of the humerous in the action of pulling something out of the back pocket
insert in the same place
part of the movers of the shoulder joint
Where is the coracobrachiallis muscle located?
extended from the coracoid process of the scapula to the humerous
What are the actions of the coracobrachiallis?
flexion + abduction of the arm
What muscles are movers of the shoulder joint?
deltoid mucles pectoralis major latissimus dorsi teres major coracobrachiallis biceps brachii triceps brachii
What is the action of anterior muscles of the upper limb?
flexion
What is the action of posterior muscles of the upper limb?
extension
What are the anterior muscles of the arm?
biceps brachii
brachialis
What are the actions of the anterior muscles of the arm?
flexion of the forearm
What are the actions of the biceps brachii?
flexion of the arm
supination of the forearm
flexion of the forearm
What are the actions of the brachialis
only flexion of the forearm
What are the actions of the posterior muscles of the arm?
extension of the forearm
What are the muscles in the posterior group of muscles of the arm?
triceps brachii
anconeous
What are the actions of the triceps brachii
extension of forearm
extension of arm
What are the actions of the anconeous muscle
extension of the forearm
Describe the muscles of the forearm that move the hand and fingers
- divided into anterior and posterior groups
- antagonize each ther
What are the actions of the anterior group of muscles of the forearm that move the hand and fingers?
- flexion of hand + fingers
- pronation of forearm
What are the actions of the posterior group of muscles of the forearm that move the hand and fingers?
- extension of hand and fingers
- supination of the forearm
What are the groups of the intrinsic muscles of the hand called?
- thenar eminence
- hypothenar eminence
- midpalmar (intermediate)
Describe the thenar eminence
palpable bulge of muscles in lateral side of the hand
acts on the the thumb
Describe the hypothenar eminence
palpable muscles in the medial side of the hand,
acts on the 5th finger
describe the midpalmar
- inbetween thenar and hypothenar eminences
- includes: interossei + lumbrical muscles
- acts on add digits EXCEPT thumb
What are the functions of the lower extremities?
- supporting body’s weight
- maintaining the equilibrium
- locomotion
- kicking, jumping, running, walking etc.
What groups are the muscles of the gluteal muscles divided into?
- gluteal muscles + tensor fasciae latae
- deep lateral rotators of the thigh
What muscles do the gluteal muscles include?
- gluteus maximus
- gluteus minimus
- gluteus medius
What are the actions of the gluteal muscles?
extension
abduction
lateral rotation of the thigh
What is the ITB?
iliotibial band
tendon of the tensor facia latae and tendon of gluteus maximus
Where does the ITB insert?
tibia
How is the tensor fascia latae
+ ITB placed?
laterally placed
