Transcript Scapular Region

Scapular Region
Dr. Sama-ul-Haque
Dr. Rania Jabr
Scapular Region
Objectives
 Know the principal muscles of the scapular
and scapulo-humeral regions.
 Understand the mechanism of scapular rotation
in relation with shoulder movements.
Bones of the shoulder region: The
SCAPULA
Anterior
Posterior
Muscles of The
Shoulder Region
 These muscles connect
scapula to humerus (move
humerus through shoulder
joint).
1. Deltoid.
2. Supraspinatus.
3. Infraspinatus.
4. Teres minor.
5. Teres major.
6. Subscapularis.
Posterior view
1
2
3
4
5
Anterior view
6
Surface Anatomy
Acromion (of scapula
• Spine
Trapezius muscle
Infraspinatus
muscle
Teres minor
muscle
Triangle of
ascultation
Teres major
muscle
Deltoid
Lateral third of clavicle,
acromion, spine of scapula
Deltoid tuberosity of
humerus
Nerve supply:
Axillary nerve
Action:
Anterior fibers : Flexion, medial rotation
Middle fibers: abduct arm from 15°- 90°.
Posterior fibers : Extension, lateral
rotation
D
Abductors of shoulders:
1. Supraspinatus 0-15 degree.
2. Deltoid 15-90 degree.
3. Trapezius & serratus anterior: abduction 90-180 degree.
4 Rotator cuff muscles: stabilize the shoulder joint.
Supraspinatus, Infraspinatus,
Subscapularis, Teres minor
Rotator Cuff Muscles
Supraspinatus
Origin: supraspinous fossa.
Insertion: greater tuberosity of humerus.
Nerve supply: suprascapular nerve.
Action: abduction of humerus from 0° - 15°.
Infraspinatus:
Origin: infraspinaous fossa.
Insertion: greater tuberosity of humerus.
Nerve supply: suprascapular nerve.
Action: lateral rotation of humerus.
Teres minor
Origin: lateral border of scapula
Insertion: greater tuberosity of humerus.
Nerve supply: axillary nerve.
Action: lateral rotation of humerus.
Teres major:
Origin: lateral border of scapula
Insertion: bicipital groove of humerus (med lip)
Nerve supply: lower subscapular nerve.
Actions: extension, adduction & medial rotation
of humerus (swimming).
Subscapularis
Origin: subscapular fossa.
Insertion: lesser tuberosity of humerus.
Nerve supply: upper & lower subscapular nerves.
Action: medial rotation of humerus.
Transverse scapular ligament
• Attach to suprascapular notch
• Subscapular nerve (C5,6) below it and Subscapular artery above it,
Serratus anterior
Front of the
medial border of
scapula.
Nerve supply:
• Long thoracic nerve.
Action:
• Depression & protraction
of the scapula (boxing)
• Raising the arm above 90
degree (climbing).
• Accessory muscle of
respiration
Injury of long thoracic nerve
Subscapularis
Injury of long thoracic
nerve: Winged Scapula:
Cause; Paralysis of serratus anterior as it is
"big swing muscle" or "boxer's muscle”
Antagonist of Rhomboids
Complete abduction at the shoulder joint requires
superior rotation of the scapula so that the glenoid
fossa faces superiorly.
Glenoid fossa
• Superior rotation of
Glenoid fossa: trapezius
serratus anterior
Scapula rotates when we move
our arms to allow more range
of motion at the shoulder joint
Posterior scapula