Shoulder Complex- shoulder girdle

Question 1

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What parts make up the shoulder arm complex?

Answer 1

• scapula
• clavicle
• humerus

Question 2

What joint connects the shoulder complex to the axial skeleton?

Answer 2

sternoclavicular joint (true joint)

Question 3

What are the joints of the shoulder complex?

Answer 3

• Glenohumeral-true joint
• Acromioclavicular-true joint
• Sternoclavicular- true joint
• Scapulothoracic- physiological joint

Question 4

What 2 bones make up the shoulder girdle?

Answer 4

1. scapula
2. clavicle (it connects the scapula to the axial skeleton)

Question 5

What joint do movements at the shoulder girdle occur at?

Answer 5

The scapulothoracic joint (physiological joint)

Question 6

What other 2 joints is the scapulothoracic joint linked to?

Answer 6

1. acromioclavicular
2. sternoclavicular

Question 7

Be able to lable the anatomy of the scapula

Answer 7

-do this on the ipad

Question 8

What are the 4 translatory movements of the scapula?

Answer 8

1. Elevation (frontal plane)
2. depression (frontal plane)
3. retraction (medial movement towards the spine) [transverse plane motion)
4. protraction (lateral movement away from spine) [transverse plane motion]

Question 9

What are the rotary movements of the scapula?

Answer 9

This rotation allows for GH flexion beyond 100 degrees

1. upward rotation: rotation of the scapula in the frontal plane; the acromion process and glenoid fossa move upwards
2. downward rotation: rotation in the frontal plane with the acomion process and glenoid fossa moving downwards

Question 10

What are the acessory movements of the scapula?

Answer 10

• Vertebral winging: where the wings of the scapula start to come away from the vertebrae (think of a hug)
• Upward tilt (on the surface of the thorax)
• Downward tilt (on the surface of the thorax)

These motions accompany the muscle produced movements and occur as a result of the rigid scapular bone being pulled around a curved thorax

Question 11

What is the purpose of the sternoclavicular joint?
What movements does it contribute to?

Answer 11

• to attach the clavicle to the sternum
• prevents downward motion of the clavicle

Translatory movements: contributes most to the GH joint during teh 1st 90 degress of movement

• elevation/depression
• protraction/retraction
• upwards tilt (accessory–> sagittal plane, frontal axis)

Question 12

What is the purpose of the acromioclavicular joint?
What motions does it contribute to?

Answer 12

Purpose:
* to maintain the relationship between the clavicle and scapula (in the early stages of elevation of upper limb to allow the scapula additional range of rotation on the thorax in the later stages of elevationof the limb)

Motions: rotary movements of scapulothoracic joint
* upward/downward rotation
* Winging
* Upward/downward tilt

Contributes most to movemnet at the GH ABOVE 90 degrees (if issues here you will feel pain in high ends of GH flexion and abduction)

Question 13

What type of joint is the glenohumeral joint?

Answer 13

diarthrotic ball and socket joint

Question 14

Is the subdeltoid an anatomical joint? Explain

Answer 14

The subdeltoid is not an anatomical joint, it is a phsyiological joint.

• comprises 2 surfaces moving with respect to each other [the head of the humerus moving towards the coracoacromial arch]
• the subdeltoid is mechanically linked to the GH joint, –> so we see how movement at one joint can influence movement in another

Question 15

What are the 3 major ligaments of the shoulder girdle?

Answer 15

• acromioclavicular
• coracoclavicular
• coracoacromial

Question 16

What does the acromioclavicular ligament do?

Answer 16

• prevents posterior dislocation of the clavicle
• commonly injured in active people

Question 17

What does the coracoclavicular ligament do?

Answer 17

• provides joint stability
• firmly unites the clavicle and scapula
• checks backwards motions of the scapula
• the most frequently injured ligamnet of the shoulder complex

Question 18

What does the coracoacromial ligament do?

Answer 18

• forms coracoacromial arch, which is there to prevent trauma to the humeral head and sensitive muscles, tendons, and bursae overlying the humeral head

Question 19

Describe the trapezius muscle

Answer 19

• O: 1) Occipital bone & ligamentum nuchae, 2) spinous process of C7, 3) all thoracic vertebrae
• i: 1) posterior border of lateral 3rd of clavicle. 2) top of acromion process and upper border of scapula spine. 3). root of spine of scapula
  * A: 1) elevation and upward rotation, 2) retraction. 3) depression and upward rotation

Question 20

Describe the levator scapula muscle?

Answer 20

This muscle works with fibers of upper traps to produce scapula elevation
* O: TP on the 1st cervicle vertebrae
* I: the vertebral border of the scapula betwen the medial angle and the scapular spine
* A: scapular elevation and scapula downward rotation
* Nerves: dorsal scapula ans branches from the 3rd and 4th cervical nerves

Question 21

Describe the rhomboid muscles?

Answer 21

They lie beneath the middle fibes of the trapezius, they are 2 parts: the major and minor

• O: spinous process of the 7th cervical and 1st 5 thoracic vertera (C7-T5)
• Insertion: vertebral border of scaoula from the spine to the inferior angle
• A: scapular downward rotation, retraction, elevtaion
• Nerve: dorsal scapula

Question 22

Describe the serratus anterior?

Answer 22

• O: outer surface of ribs 1-9 at the side of the chest
• I: anterior surface of the verterbral border of the scapula from spine to inferior angle– the fibers lie between the scapula and ribs
  * A: scapula protraction/scapula upward rotation

Question 23

Describe the pectoralis minor

Answer 23

• O: anterior surface of ribs 3-5 near cartilage
• I: tip of coracoid process of scapula
  * A: protraction and downward rotation

Question 25

Describe the subclavius?

Answer 25

• O: upper surface of 1st rib where it joins cartilage
• I: on the groove extending along the middle half of the underside of the clavicle
• A: stabilizes the clavicle (it limits excessive elevation and protraction of clavicle)