Shoulder Region Flashcards
Muscles of shoulder region divided into what categories?
1.Extrinsic: originate from torso and attach to scapula, clavicle or humeus
- Intrinsic: originate from scapula/clavicle and attach to humerus
What are the extrinsic mucles of shoulder region (that connect upperlimb to vertebral column)?
Superficial
1.Trapezius
2.Latissimus dorsi
Deep
3. Levator scapula
4. Rhomboid Minor
5. Rhomboid Major
Where are extrinsic muscles of shoulder region located?
In the back- known as superficial back muscles
Shape of trapezius muscle?
Triangular
Nerve supply of trapezius muscle?
Spinal part of Accessory nerve (11th cranial nerve)
Cervical plexus C3 and C4
How many parts of trapezius?
And what are their origin and insertion?
3 parts:
-
Descending (superior) part:
Origin:
-occipital bone
- nuchal ligament
-spine of 7th cervical vertebrae
Insertion:
lateral 3rd of clavicle
-
Transverse (middle) part:
Origin:
spinal processes of 1st — 4th thoracic vertebrae
Insertion:
Acromion
-
Ascending (inferior) part:
Origin:
5th -12th thoracic vertebrae**
Inserts
scapular spine
Action of trapezius?
Stabilizes shoulder blade (scapula)
- Upper fibre-
Elevate the scapula
Scapular elevation - Middle fibres-
Pull the scapula medially
Scapular retraction - lower fibres-
Pull down the medial border of scapula
Scapular depression
Also
Cervical spine extension and hyperextension
Which part of trapezius inserts at the spine of scapula?
Ascending or inferior group of fibres
Which part of trapezius inserts into acromion?
Transverse or middle fibres
Which part of trapezius inserts at the lateral 3rd of clavicle?
Descending or superior fibres
Vascular supply of trapezius?
1.Occipital Artery- descending fibres
-
Transverse Cervical Artery-
Transverse fibres -
Dorsal Scapular Artery-
Ascending fibres
Lateral flexion of cervical spine is caused by which muscle?
Trapezius
What is meant by term iatrogenic in anatomy?
Iatrogenic refers to a condition or illness that is caused by medical treatment or procedures.
an injury that is caused by a medical professional.
What is biopsy?
Biopsy is a medical procedure that involves removing a small sample of tissue for examination.
What is accessory nerve?
And accessory nerve damage?
The accessory nerve is a cranial nerve that controls the movement of certain muscles in the neck and shoulders, including the :
trapezius and sternocleidomastoid muscles.
Damage to the accessory nerve can result in weakness or paralysis of the muscles it controls, leading to difficulty moving the head and shoulders.
What are the causes of accessory nerve damage?
Iatrogenic causes (due to a medical procedure)
1. Cervical lymph node biopsy
2. Cannulation of internal jugular vein
How accessory nerve damage is tested?
By assessing Trapezius function
Origin of latissimus dorsi?
Spinal process of lower six thoracic vertebrae (T7- T12)
Lumbar vertebrae (l1- l5)
Ileac crest
Sacrum
Inferior angle of scapula
Lower 3 or 4 ribs
Insertion of latissimus dorsi?
And its insertion point lies between which 2 muscles?
Floor of the bicipital groove (Intertubercular sulcus) of humerus
Between:
(The lady between two majors)
- Pectoralis major(inserts to lateral lip of intertubercular groove)
- Teres Major ( inserts to medial lip of intertubercular groove)
Nerve supply of latissimus dorsi?l
Thoracodorsal nerve
Which artery supplies latissimus dorsi?
Thoracodorsal Artery
Action of latissimus dorsi?
Extends
Adducts
Medially rotates the arm
What is the largest muscle of the back?
Latissimus dorsi
The nerve fibres of latissimus dorsi arise from?
Ventral rami of spinal nerves
Thoracodorsal artery is a branch of?
Subscapular artery which is the largest branch of axillary artery
Location of levator scapula in terms of trapezius?
Deep to trapezius
Location of levator scapula?
Forms floor of lateral cervical region
Origin of levator scapula?
Transverse process of first 4 cervical vertebrae
Insertion of levator scapula?
Medial border of scapula
Nerve supply of levator scapula?
-C3 and C4
-dorsal scapular nerve
Function of levator scapula?
Elevation of medial border of scapula
Lateral flexion of cervical spine
(Trapezius muscle assists it in both of these functions)
Muscles that are deep to trapezius?
1.Levator scapula
2. Rhomboid Major
3. Rhomboid minor
Which of the rhomboids is on the upper side?
Rhomboid minor is upper
Rhomboid major is just inferior to it
Both rhomboids connect medial border of scapula to?
Vertebral column
Origin of rhomboid minor?
Ligamentum nuchae
Spine of 7th cervical vertebrae
1st thoracic vertebrae
(C7 - T1)
Insertion of rhomboid minor?
Medial border of scapula
At the level of the spine of scapula
Origin of rhomboid major?
2nd -5th thoracic spines
(T2 - T5)
Insertion of rhomboid major?
Medial border of scapula
Between scapula spine and inferior angle
Both rhomboids are supplied by which nerve?
Dorsal scapular nerve
Function of rhomboid muscles?
Scapula adduction-
Raise the medial border of scapula upward and medially
Which is the 11th cranial nerve?
And not a part of brachial plexus?
The accessory nerve
