Structures

  • Trapezius
  • Deltoid
  • Levator scapulae
  • Rhomboid minor
  • Rhomboid major

 

MuscleActionOriginInsertionInnervationBlood supply
Trapezius- Upper fibres: Elevation of scapula and rotation of scapula during humerus abduction
- Middle fibres: Retract the scapula
- Lower fibres: Depress the scapula
- Together: Extend neck
- Occiput,
- Medial margin of ligamentum nuchae
- Spinous processes of C7- T12
- Lateral third clavicle,
- Acromion process
- Spine of scapula
- Accessory nerve
- Cervical nerves: C3,4
- Transverse cervical artery
Deltoid- Anterior fibres: Flexion of arm
- Middle fibres: Abduction of arm
- Posterior fibres: Extension of arm
- Clavicle
- Acromion process
- Spine of scapula
- Deltoid tuberosity- Axillary nerve: C5,6- Deltoid branch of thoracoacromial artery
Levator scapulae- Elevates the scapula- Transverse processes of C1-4- Superomedial scapula
(above the spine of the scapula)
- Dorsal scapula nerve: C4,5
- Cervical nerves: C3,4
- Dorsal scapula artery
Rhomboid minor- Elevates and retracts the scapula
- Spinous processes C7, T1- Superomedial scapula
(at the root of the spine of the scapula)
- Dorsal Scapular nerve: C4,5- Dorsal scapula artery
Rhomboid major- Elevates and retracts the scapula- Spinous processes T2-T5- Medial scapula
(from the root of the spine of scapula to the inferior angle of the scapula)
- Dorsal Scapular nerve: C4,5- Dorsal scapula artery
Teres major- Adduction of humerus
- Medial rotation of humerus
- Extension of humerus
- Inferior angle of scapula- Medial of intertubercular groove of humerus- Lower subscapular nerve: C5,6,7- Sub scapular artery
- Circumflex scapular artery