Shoulder,Arm

Question 1

This muscle forms the shoulder’s rounded contour, being thick and spread out anteroposteriorly

Answer 1

Deltoid muscle

Question 2

When you remove the Deltoid muscle you will find the

Answer 2

Supraspinatus- posteriorly
infraspinatus- posteriorly
Teres major and minor-posteriorly
subscapularis- anteriorly

Question 3

The shoulder joint is a ball and socket joint formed by

Answer 3

the head of the humerus and the glenoid cavity

Question 4

the glenoid cavity is part of

Answer 4

the scapula

Question 5

Another word for the shoulder joint is called the

Answer 5

glenohumeral joint

Question 6

The acromioclavicular joint is

Answer 6

posterior or behind the clavicle joints

Question 7

arm rotation outward is called

Answer 7

lateral rotation

Question 8

arm rotation inward is called

Answer 8

medial rotation

Question 9

link the vertebral column or rib cage (axial skeleton) to the scapula, clavicle or humerus (appendicular skeleton).

Answer 9

Thoraco-appendicular muscles

Question 10

Thoracoappendicular muscle include

Answer 10

1)Subclavius
2) Pectoralis Minor
3) Pectoralis Major
Adducts and medially rotates the humerus.

Pectoralis Minor: Inferior rotation of the scapular glenoid.

Subclavius: Depresses the lateral end of the clavicle.

Serratus Anterior: Protracts (Abducts) the scapula and superiorly rotates the glenoid of the scapula to enable full abduction of arm.
(When the scapula is fixed, the serratus anterior muscle

Question 11

link the scapula to the humerus. These include the deltoid, the teres major muscles and the 4 rotator cuff muscles.

Answer 11

Scapulo-humeral muscles

Note that several major Arm muscles are technically “scapulohumeral” muscles. However, for the most part, these act on the elbow joint and are discussed with the arm rather than the shoulder (e.g. biceps and triceps).

Question 12

Pectoralis Major Muscle:

Answer 12

Pectoralis Major Muscle:

Origins: clavicular head, sternocostal head, abdominal head
Nerve: lateral & medial pectoral nerves. Main Function: ADDucts and medially rotates the humerus.

Question 13

Pectoralis Minor Muscle:

Answer 13

Pectoralis Minor Muscle:

Origin: upper margins of ribs 3-5
Insertion: coracoid process of scapula
Nerve: medial pectoral nerve
Main function: downward (inferior) rotation of the scapula

Question 14

Origin: lateral clavicle, spine of scapula, acromion
Insertion: deltoid tuberosity of humerus
Nerve: axillary
Function: aBducts arm, also flexes and extends arm

Answer 14

Deltoid

Question 15

Origin: inferior angle of scapula
Insertion: medial bicipital (intertubercular) groove of humerus
Nerve: lower subscapular
Function: aDDucts and medially rotates arm

Answer 15

TERES MAJOR

Question 16

Origin: supraspinous fossa of scapula
Insertion: superior part of greater tubercle of humerus
Nerve: suprascapular
Function: assists deltoid in aBducting arm

Answer 16

SUPRASPINATUS

Question 17

Origin: infraspinous fossa of scapula
Insertion: medial facet of greater tubercle of humerus
Nerve: suprascapular
Function: laterally rotates humerus

Answer 17

Infraspinatus

Question 18

Origin: posterolateral border of scapula
Insertion: lower part of greater tubercle
Nerve: axillary
Function: aDDucts and laterally rotates humerus

Answer 18

Teres Minor

Question 19

What tendon is the most commonly torn of the rotator cuff muscle. what nerve is affected

Answer 19

supraspinatus
suprascapular nerve

Question 20

Origin: subscapular fossa
Insertion: lesser tubercle of humerus; capsule of shoulder joint
Nerve: upper and lower
subscapular
Function: medially rotates humerus

Answer 20

Subscapularisg

Question 21

There are 2 muscle compartments in the arm

Answer 21

Anterior- All anterior compartment muscles are innervated by the musculocutaneous nerve
Posterior- All posterior compartment muscles are innervated by the radial nerve

Question 22

Radius is located

Answer 22

This is the shorter bone located on the lateral or **thumb side. hThe head of the radius and the radial tuberosity are proximal; the styloid process is distal.