Superficial Back/Shoulder/Scapular Region Flashcards
Superficial Posterior Axioappendicular Muscles
i.e. Extrinsic Shoulder Muscles
- Latissumus Dorsi
2. Trapezius
Latissimis Dorsi Nerve Supply
Thoracodorsal Nerve
Latissimus Dorsi Function
Extend; adduct; medially rotate the humerus @ the shoulder joint
Latissimus Dorsi Attachments
Proximal: - spinous processes of thoracic vertebra below T6 - thoracolumbar fascia - iliac crest - Lower 3 or 4 ribs Distal: - humerus intertubercular groove - fibers twist as they converge toward the humoral insertion
Trapezius Nerve Supply
Accesory Nerve (Cranial Nerve XI)
C3 & C4 (spinal nerves)
Trapezius Function
a. Upper fibers –> elevate scapula
- in rotating the scapula helps the serratus anterior in making abduction of the humerus >90 degrees possible
b. Middle Fibers –> retract scapula
c. Lower Fibers –> depress scapula
“Droopy” shoulder injury
A paralysis of the trapezius muscle resulting from an injury to the accessory (aka cranial XI) nerve
Deep Axioappendicular Muscles
Extrinsic Shoulder Muscles
- Levator Scapulae
- Rhomboidei (major & minor)
- Serratus Anterior
Levator Scapulae nerve supply
Dorsal Scapular Nerve
Levator Scapulae function
elevate and fix the scapula
Rhomboid (major and minor) nerve supply
Dorsal Scapular Nerve
Rhomboid function
Retract and elevate the scapula
Serratus Anterior Nerve Supply
Long Thoracic Nerve
Serratus Anterior function
Protracts the scapula holds it against the thoracic wall
Paralysis of the Serratus Anterior
Due to problem with long thoracic nerve. Results in Winged Scapula
Scapulohumeral Muscles
Intrinsic Shoulder Muscles
- Deltoid
- Teres Major
- Superspinatus
- Infraspinatus
- Teres Minor
- Subscapularis