Shoulder Girdle Muscle Ins/Act/Org

Levator Scapulae — Action

• Raises (elevates) scapula
• Elevates and retracts the scapula

Levator Scapulae — Origin

Transverse processes of upper four cervical vertebrae (C1–C4)

Levator Scapulae — Insertion

Superior medial border of scapula

Trapezius — Actions (Upper)

• Upper fibres: Elevate scapula and clavicle; extend head

Trapezius — Actions (Middle)

• Middle fibres: Elevate, upwardly rotate and adduct scapula

Trapezius — Actions (Lower)

• Lower fibres: Depress, adduct and upwardly rotate scapula

Trapezius — Actions (Upper, Lower)

• Upper & lower together: Rotate scapula upwardly (important when arm is elevated)

Trapezius — Insertions

• Upper fibres: Base of skull, occipital protuberance, posterior ligaments of neck

Trapezius — Insertions

• Middle fibres: Spinous processes of C7 and upper three thoracic vertebrae (T1–T3)

Trapezius — Insertions

• Lower fibres: Spinous process of T4 to T12 vertebrae

Trapezius — Insertions upper fibres

• Upper fibres: Lateral third of clavicle

Trapezius — Insertions middle fibres

• Middle fibres: Acromion and upper border of spine of scapula (tubercle)

Trapezius — Insertions Lower fibres

• Lower fibres: Medial portion of crest of spine of scapula (tubercle)

Rhomboid Muscles (Major & Minor) — Action

• Adducts (retracts) and slightly raises scapula towards spinal column
• Rotates scapula downwards

Rhomboid Muscles (Major & Minor) — Origin

Spinous processes of last cervical (C7) vertebra and first five (T1–T5) thoracic vertebrae

Rhomboid Muscles (Major & Minor) — Insertion

Medial border of scapula below spine

Serratus Anterior — Action

• Abducts (protracts) scapula
• Rotates scapula upwards
• Stabilises scapula when hand exerts pressure on an object (e.g., in press-ups)

Serratus Anterior — Origin

Ribs 1–9 at side of chest

Serratus Anterior — Insertion

Anterior surface of medial border of scapula

Pectoralis Minor — Action

• Abducts (protracts) and draws scapula laterally away from spinal column
• Draws scapula forwards and downwards (depresses & tilts scapula)

Pectoralis Minor — Origin

Anterior surfaces of ribs 3–5

Pectoralis Minor — Insertion

Coracoid process of scapula