Editing Diaphragm (section)

== '''Nerve supply:''' ==

* Motor supply is solely from     the phrenic nerves
** Arise from C3, 4 and 5; but      mostly C4. Passes inferiorly over the anterior surface of anterior      scalene, deep to pre-vertebral fascia. Posterior to subclavian vein and      anterior to subclavian artery.
*** Right: descends anteriorly       over right lung root; courses along the pericardium of the right atrium;       pierces diaphragm at IVC opening
*** Left: descends anteriorly       over left lung root; crosses aortic arch and bypasses the vagus nerve;       courses along pericardium of LV; pierces the left hemidiaphragm
** Each half of the diaphragm      is supplied by its own phrenic nerve, even the fibres of the right crus      that loop to the left around the oesophageal opening are supplied by the      left phrenic
** On reaching the abdominal      surface of the diaphragm, both nerves divide into anterior, lateral and      posterior branches which run radially, giving off branches that enter the      muscle from below
** Phrenic variants:
*** Pierced scalene
*** Anterior to subclavian       artery
*** Additional branches from       cervical nerve roots
*** Accessory phrenic nerve       from C5 and C6
* Sensory is from intercostal     nerves peripherally and phrenic nerves centrally
** Pain referred to      shoulder-tip