Week 5 Flashcards
What are the joints involved in the shoulder girdle?
1) Sternoclavicular joint
2) Acromioclavicualr joint
3) Scapulothoracic joint
True or false: the glenohumeral joint is the shoulder joint
True
True or false: the scapulothoracic joint is an articular structure
False
They are on the rib cage attached by various structures and the scapula can move freely on the ribcage
What are the joint motions
- elevation/depression
- protraction/retraction
- upward rotation/downward rotation
- scapular tilt
elevation/depression: lifting scapula up and down (shoulder shrug)
protraction/retraction: moving scapula laterally and medially (away from midline and towards midline)
upward rotation/downward rotation: when lifting arm up beside you, scapula rotates toward midline
scapular tilt: when lifting arm up in front of you, scapula tilts back, naturally tilts forward
When does the shoulder go into hyperextension?
–> superior end tilts anteriorly
–> inferior end tilts posteriorly
True or false: it is possible to move the shoulder girdle without moving the humorous during LINEAR movements
True
True or false: it is possible to move the shoulder girdle without moving the humorous during ROTATION movements such as abduction and adduction
False
What must the scapula move with?
The glenohumeral joint
True or false: impairment at one joint of the shoulder does not directly impair the function at another
False
Impairment at one joint will impair function at other
What is scapulohumeral rhythm?
First 30 degrees of shoulder joint movement is ALL shoulder joint motion
After 30 degrees -
For every 2 degrees of shoulder flexion or abduction that occurs, the
scapula must upwardly rotate 1 degree
2:1 ratio of the shoulder (2) and scapula (1)
What is the scapulohumeral rhythm ratio?
2:1
(fFor every 2 degrees of shoulder flexion or abduction that occurs:
Scapula must upwardly rotate 1 degree)
Where is the scapula found (at rest)?
between the 2nd and 7th ribs
Medial (vertebral) border 2-3” from spinous process
True or false: the sternoclavicular joint is very mobile
False
–> this joint has limited mobility
What is the relationship between the clavicle and sternum in the sternoclavicular joint?
When the clavicle moves, the sternum remains stationary
What is the acromioclavicular joint?
Connects acromion process to clavicle
–> Relatively weak
–> Ligaments help stabilize
True or false: the Acromioclavicular joint
is relatively weak and therefore the ligaments help stabilize
True
What are the muscles of the shoulder girdle?
1) Trapezius (upper, middle, lower)
2) Levator scapula
3) Rhomboids
4) Serratus anterior
5) Pectoralis minor
What is the origin of the upper trapezius?
- Occipital bone
- nuchal ligament (cervical spinous process)
What is the insertion of the upper trapezius?
Lateral clavicle
Acromion process
What action does the upper trapezius perform?
Elevate scapula and upward rotation
What are some roles/functions of the upper trapezius?
- Upward diagonal pull
- Prime mover for scapular elevation and upward rotation
- Assists in retraction
What is the origin of the middle trapezius?
Spinous process of lower C and upper T vertebrae
What is the insertion of the middle trapezius?
Acromion process and spine of scapula
What action does the middle trapezius perform?
Scapular retraction
What are some characteristics/functions of the middle trapezius?
- Horizontal pull
- Retracts scapula
- Assists in upward rotation of scapula
- Weak upper rotator,
- Not very well leveraged
What is the origin of the lower trapezius?
Spinous process of middle-lower T vertebrae
What is the insertion of the lower trapezius?
Spine of scapula (base)
What action does the lower trapezius perform?
Scapular depression and upwards rotation
True or false: muscle actions are dependent on joint positions
True
What are some roles/functions of the lower trapezius?
Downward diagonal pull
Depresses scapula and upwardly rotates
What is the origin of the levator scapula?
Transverse process of C1-C4
What is the insertion of the elevator scapula?
Superior angle of spine
What action does the elevator scapula perform?
Elevates scapula and rotates down
What are some characteristics/functions of the elevator scapula?
- Covered by trapezius muscle
- Deep to traps
- Prime mover for scapular elevation
-Pulls the origin and insertion together which results in elevation (downward rotation occurs as well)
What is the origin of the rhomboids?
Spinous process of C7-T5
What is the insertion of the rhomboids?
Vertebral border of scapula
What action does the rhomboids perform
Retraction, elevation, downward rotation
What are some characteristics/funtions of the rhomboids?
- Consist of 2 muscles
Minor and major - Functionally, have the same actions
What is the origin of the serrates anterior?
Lateral surface of 8 ribs
What is the insertion of the serrates anterior?
Vertebral border of scapula (anteriorly)
What action does the serrates anterior perform?
- Scapular protraction
- Upward rotation of scapula
What are some characteristics/functions of the serratus anterior?
- Saw-tooth pattern of attachment on the anterior thorax
Keeps scapula against posterior rib cage to prevent “winging”
- Wraps around the ribcage
What is the origin of the pectoralis minor?
Ribs 3-5
What is the insertion of the pectoralis minor?
Coracoid process of scapula
What are some characteristics/functions of the pectoralis minor
- Found deep to pectoralis major
- Downward diagonal line of pull almost vertical
- Prime mover for scapular depression, downward rotation and tilt
What action does the pectoralis minor perform?
Depression, protraction, down rotation, and tilt of scapula
