Origin: Spinous process of T7-12, the lower 3 or 4 ribs, the thoracolumbar fascia of the lumbar and sacral vertebra, the medial 3rd of the posterior iliac crest and in some an attachment to the inferior angle of the scapula.
Insertion: The intertubercular or bicipital groove of the Humerus.
Action: Medially rotates, adducts and extends the arm, depresses the shoulder girdle. Assists in lateral flexion of the torso, tilting the pelvis anterior and laterally and hyper extending the spine.
Position: With elbow held straight adduct and extend the arm to a position parallel to the body 5° posterior to the midline (ie hand pressed against table).
Rotation: Medially rotate Humerus (little finger upwards, thumb on table side).
Stabilise: Same side pelvis.
Monitor: Apply pressure at the forearm above the wrist to abduct the arm with slight flexion.
Nerve Supply: Thoracodorsal - C6, C7, C8.
Anterior: Bilateral 2cm from the midline, 2cm superior to the pubic symphysis
Posterior: Bilateral transverse process of L2.
Neuro-Vascular Reflex: Bilateral frontal eminences.
Yuan Point: Bl64
Nutrition: Vit. A.