<P> The usual branches of the subclavian on both sides of the body are the vertebral artery , the internal thoracic artery , the thyrocervical trunk , the costocervical trunk and the dorsal scapular artery , which may branch off the transverse cervical artery which is a branch of the thyrocervical trunk . The subclavian becomes the axillary artery at the lateral border of the first rib . </P>
where does the subclavian artery become the axillary
at the lateral border of the first rib