Scapular Region Dr. Sama-ul-Haque Dr. Rania Jabr

Scapular Region artmiller.medicalillustration.com

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 acromion anatomical neck coracoid process Lesser tubercule glenoid cavity surgical neck anatomical neck Greater tubercule Lesser tubercule bicipital groove

Posterior Acromioclavicular joint Supraspinous Fossa anatomical neck Infraspinous Fossa Radial Groove Deltoid Tuberosity surgical neck anatomical neck Acromioclavicular joint Spine

Muscles of The Shoulder Region Posterior view These muscles connect scapula to humerus (move humerus through shoulder joint). Deltoid. Supraspinatus. Infraspinatus. Teres minor. Teres major. Subscapularis. 2 1 3 4 5 Anterior view 6

Surface Anatomy Spine Acromion (of scapula Trapezius muscle Infraspinatus muscle Triangle of ascultation Teres major muscle Teres minor muscle

Deltoid Action: Nerve supply: 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: Supraspinatus 0-15 degree. Deltoid 15-90 degree. Trapezius & serratus anterior: abduction 90-180 degree.

4 Rotator cuff muscles: stabilize the shoulder joint. Supraspinatus, Infraspinatus, Subscapularis, Teres minor Subscapularis Subscapularis Anterior view Supraspinatus Infraspinatus Superior view Teres Minor Posterior view

Rotator Cuff Muscles

Supraspinatus Infraspinatus: 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 Teres major: 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 Upper 8 ribs Nerve supply: Action: Front of the medial border of scapula. Upper 8 ribs 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 en.wikipedia.org/wiki/Serratus_anterior_muscle 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

Glenoid fossa: trapezius & 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

Trapezius Rhomboids Deltoid Teres Major Latissimus Dorsi

Posterior scapula