Muscles Flashcards
(34 cards)
What are the Superficial Extrinsic Shoulder Muscles and the Deep Extrinsic Shoulder Muscles?
Superficial: Trapezius Latissimus Dorsi Deep: Levator Scapulae Rhomboids
What are the Scapulohumeral Muscles?
Deltoid, Teres Major
What are the rotator cuff muscles?
Supraspinatous
Infraspinatus
Teres Minor
Subscapularis
What are the Trapezius attachments?
Origin - Axial Skeleton (Skull down to T12)
Attachments - Posterior surface of scapula and clavicle
What is the Trapezius Innervated by?
Accessory Nerve (C3 and C4)
Trapezius actions
Upper fibres rotate and elevate scapula
Middle fibres retract scapula
Lower fibres pull scapula inferiorly
How can you test the accessory nerve?
Elevate shoulder against resistance
Latissimus Dorsi attachments
Originates thoracic spine, iliac crest and the inferior 3 ribs.
Attaches to intertubecular groove of humerus
Latissimus Dorsi innervation
Thoracodorsal nerve
Latissimus Dorsi actions
Extension of the arm at the shoulder
Adduction at the shoulder
Medial rotation of the arm
Levator Scapulae attachments
Transverse processes of C1-C4 vertebrae
Attaches to the medial border of the scapula, superior to spine
Levator Scapulae innervation
Dorsal scapular nerve
Levator Scapulae actions
Elevates scapula
Rotates scapula to tilt glenohumeral joint inferiorly
Rhomboid attachments
Minor: C7-T1 vertebrae
Major: T2-T5 vertebrae
Attach medial border of scapula
Rhomboid innervation
Dorsal scapula nerve
Rhomboid Actions
Retracts scapula
Rotates scapula to tilt glenohumeral joint inferiorly
Can also fix the scapula to the thoracic wall
Deltoid attachments
Originates: Scapula and Clavicle
Attachments: Deltoid tuberosity on the lateral surface of the humerus
Deltoid Innervation
Axillary nerve
Deltoid Actions
Anterior: flex the arm at the shoulder
Posterior: extend the arm at the shoulder
Middle: major abductor of the arm 15-90
Teres Major attachment
Originate: the inferior angle of the scapula on the posterior side
Attachment: intertubecular groove of the humerus
Teres Major innervation
lower subscapular nerve
Teres Major actions
Adducts at the shoulder
medially rotates the arm
Supraspinatus attachments
Originates from the supraspinous fossa on the posterior surface of the scapula
Attachment: greater tuberosity of the humerus
Supraspinatus innervation
suprascapular nerve