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Serratus Posterior Superior
Insertion: The upper borders of the 2nd-5th ribs.
Actions: Aids inspiration by elevating ribs.
Daily uses: Inspiration/ breathing.
Serratus Posterior Inferior
Insertion: Inferior borders of ribs 9-12.
Actions: Depresses the lower ribs aiding in expiration.
Innervation: Intercostal nerves.
Daily uses: Expiration
Other muscles …
Origin: Supraspinous fossa
Insertion: Greater tuberosity of the humerus
Actions: Abduction Stabilisation of the humerus
Innervation: Suprascapular nerve
Daily uses: Holding shopping bags away from the body
Origin: Mid section of the lateral border of the scapula
Insertion: Greater tuberosity on the humerus
Actions:External rotation, Shoulder adduction
Innervation: Axillary nerve
Daily uses: Brushing hair
Origin: Anterior (costal) surface of the scapula
Insertion: Lesser tuberosity of the humerus
Actions: Internal rotation , Adduction
Innervation: Upper and lower subscapular nerves
Daily uses: Tucking the back of your shirt into your trousers