Transcript WINDSOR UNIVERSITY SCHOOL OF MEDICINE St.Kitts

DEPARTMENT OF ANATOMY
UPPER LIMB
SHOULDER
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The shoulder is the region of upper limb
attachment to the trunk and neck.
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A large muscle that arises from two heads
flexes and medially rotates the arm. It is
innervated by nerves arising from different
cords of the brachial plexus. This is the:
A.Latissimus dorsi
B.Trapezius
C.Deltoid
D.Subscapularis
E.Pectoralis major
Clavicle and scapula, which form the pectoral girdle
(shoulder girdle)
 The proximal end of the humerus.
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Muscles
1.
PECTORALIS MAJOR
2.
PECOTORALIS MINOR
3.
SUBCLAVIUS
4.
SERRATUS ANTERIOR
Origin: Clavicle, sternum, and upper six costal
cartilages
 Insertion : Lateral lip of bicipital groove of humerus
 N. supply: Medial and lateral pectoral nerves
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Action : Adducts arm and rotates it medially;
clavicular fibers also flex arm
Origin: Third, fourth, and fifth
ribs
 Insertion : Coracoid process of
scapula
 N. supply: Medial pectoral
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nerve
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Action: Stabilizes scapula by
drawing it inferiorly
Origin: First costal cartilage
 Insertion : Clavicle
 N. supply: Nerve to
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subclavius
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Action: Depresses the
clavicle
Origin: Upper eight ribs
 Insertion :Anterior surface
of medial border of scapula
 N. supply: Long thoracic
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nerve
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Action: Protracts scapula
and rotates scapula
Due to loss of Innervation-long thoracic nerve
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When the serratus
anterior is paralyzed
owing to injury to the long
thoracic nerve, the medial
border of the scapula
moves laterally and
posteriorly away from the
thoracic wall, giving the
scapula the appearance of
a wing.
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All the following muscles have a relationship
to the scapula. If paralyzed, which muscle
results in winging of the scapula with inability
to elevate the arm above the horizontal?
A .Serratus anterior
B. Latissimus dorsi
C .Levator scapulae
D. Rhomboid major
E .Deltoid
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The posterior axioappendicular muscles attach the superior
appendicular skeleton (of the upper limb) to the axial
skeleton (in the trunk).
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1.Trapezius
2.Latissimus dorsi
3. Rhomboid major and minor
4. Levator scapulae
Origin: Occipital bone, ligamentum
nuchae, spine of seventh cervical
vertebra, spines of all thoracic
vertebrae
 Insertion : Upper fibers into lateral
third of clavicle; middle and lower
fibers into acromion and spine of
scapula
 N. supply: Spinal part of
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accessory nerve (motor)
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Action: Upper fibers elevate the
scapula; middle fibers pull scapula
medially; lower fibers pull medial
border of scapula downward
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The primary clinical
manifestation of accessory
nerve palsy is a marked
ipsilateral weakness when
the shoulders are elevated
(shrugged) against
resistance.
Origin: Iliac crest, lumbar fascia, spines of
lower six thoracic vertebrae, lower three or
four ribs, and inferior angle of scapula
 Insertion: Floor of bicipital groove of humerus
 N. supply:Thoracodorsal nerve
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Action:
Extends, adducts, and
medially rotates the arm
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Surgery in the inferior part of the axilla puts
the thoracodorsal nerve supplying the
latissimus dorsi at risk of injury.
With paralysis of the latissimus dorsi, the
person is unable to raise the trunk with the
upper limbs, as occurs during climbing.
Origin: Transverse
processes of first four
cervical vertebrae
 Insertion: Medial
border of scapula
 N. supply:dorsal
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scapular nerve
 Action:Elevates
scapula
N. supply: Dorsal
scapular nerve
 Action: Retracts
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scapula
An 34 year old man, bleeding from a stab wound
in the neck, is brought to the emergency
department. After the bleeding has been
controlled, further examination indicates that
her left shoulder is lower than the right shoulder.
Which of the following nerve is most likely
injured?
 A Long thoracic
 B Dorsal scapular
 C Axillary
 D Suprascapular
 E Spinal accessory
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A 22 year old woman sustains a traumatic
injury to the axilla that severely damages the
thoracodorsal nerve. Which of the following
movements is most likely affected in this
patient?
a Adduction
B. Flexion
C Lateral rotation
D Protraction
E Supination
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Scapulohumeral muscles:
The six scapulohumeral muscles are relatively short muscles
that pass from the scapula to the humerus and act on the
glenohumeral joint.
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1.Deltoid
2.Teres major
3.Teres minor
4.Supraspinatus
5.Infraspinatus
6.Subscapularis
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Origin: Lateral third of clavicle, acromion,
spine of scapula
 Insertion: Middle of lateral surface of shaft of
humerus
 N. supply: Axillary nerve
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Action:
Anterior part: flexes and
medially rotates arm
Middle part: abducts arm
Posterior part: extends and
laterally rotates arm
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The examiner
resists the
patient's
abduction of the
limb by the
deltoid.
If the deltoid is
acting normally,
contraction of the
middle part of the
muscle can be
palpated.
The deltoid is a common site for the
intramuscular injection of drugs.
The axillary nerve runs transversely
under cover of the deltoid at the level of
the surgical neck of the humerus.
The deltoid atrophies when the axillary nerve (C5 and
C6) is severely damaged.
Origin: Lower third of lateral border of
scapula
 Insertion:Medial lip of bicipital groove of
humerus
 N. supply:Lower subscapular nerve
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Action:Adducts and medially rotates
arm
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Four of the
scapulohumeral muscles
supraspinatus,
infraspinatus, teres minor,
and subscapularis (referred
to as the SITS muscles) are
called rotator cuff muscles
because they form a
musculotendinous rotator
cuff around the
glenohumeral joint.
Origin: Supraspinous fossa of scapula
 Insertion: Superior facet of greater tubercle
of humerus
 N. supply: Suprascapular nerve
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Action: Initiates and assists deltoid in
abduction of arm and acts with rotator
cuff muscles.
Origin: Infraspinous fossa of scapula
 Insertion: Middle facet of greater tubercle of
humerus
 N. supply: Suprascapular nerve
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Action: Laterally rotates arm and
stabilizes shoulder joint
Origin: Middle part of lateral border of
scapula
 Insertion: Inferior facet of greater tubercle of
humerus
 N. supply:Axillary nerve
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Action:Laterally rotates arm and
stabilizes shoulder joint
Origin: Subscapular fossa (most of anterior
surface of scapula)
 Insertion: Lesser tubercle of humerus
 N. supply: Upper and lower subscapular
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nerves
 Action: Medially rotates and adduct arm
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Trauma may tear or
rupture one or more
of the tendons of the
SITS muscles; that of
the supraspinatus is
most commonly
involved.
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Which of the following muscles listed
below is the rotator cuff muscle involved in
medial rotation of the humerus?
A Supraspinatus
B Subscapularis
C Infraspinatus
D Teres minor
E Teres major
A 31 year old man is unable to raise his right arm
above his head 3 weeks after dislocating his
shoulder in a foot ball game. Examination shows
absence of rounded contour of the shoulder.
Which of the following nerves was most likely
injured?
 A. Musculocutaneous
 B. Median
 C. Axillary
 D. Ulnar
 E.Radial
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Superior border:
Teres Minor
Inferior border:
Teres Major
Lateral border:
Surgical neck of the
humerus
Medial border:
Long Head of
Triceps
▪ 1- Axillary Nerve
▪ 2- Posterir Circumflex Humeral Artery
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Quadrilateral space
syndrome usually
happens from overuse,
especially with overhead
sports like throwing and
swimming. The
syndrome can also be
caused by an injury, like a
shoulder dislocation.
LATERAL BORDER:
Long Head of the Triceps
Upper border:
Teres Minor and
subscapularis
 Lower border:
 Teres Major
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CONTENTS
Circumflex Scapular Branch
of the Subscapular artery
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Medially
long head of the triceps
brachii
Latterly
shaft of the humerus
Superiorly
teres major
▪ 1-Radial nerve
▪ 2-Profunda brachii artery