- Discussion: Upper Limb Development;
    - subclavian artery projects into the early upper limb bud & forms subclavian-axillary-brachial  trunk;
    - its distal portion becomes interosseous artery that initially supplies plexus of arteries in the primitive hand;
          - branch of trunk artery, median artery, temporarily replaces interosseous artery in supplying the hand;
          - subsequently, ulnar and then radial arteries are formed & supplies forearm and of superficial & deep palmar arches of hand;
   - deep branch of brachial artery  & arteries about shoulder & elbow arise relatively late as branches of primary axial vessel;

- Discussion: Lower Limb Development:
    - umbilical artery it gives off small branch, ischiadic artery, that temporarily serves supplies the growing limb;
    - external iliac artery, arising from umbilical artery slightly proximal to ischiadic, soon provides most of the blood supply to the limb 
          and goes on to successively,  femoral , popliteal, & posterior tibial artery;
     - anastomosis is formed as popliteal artery  passes near ischiadic, artery and the lower part of ischiadic becomes peroneal  artery;
          - anterior tibial artery is subsequently formed;
    - persisting distal portions of ischiadic artery  become peroneal & inferior genicular  arteries;
    - proximal portion persists as branch of  inferior gluteal artery, which lies anastomoses w/ lateral & MFCA  & first perforating branch of
          deep femoral artery;
          - anastomosis sometimes called cruciate or crucial anastomosis;
    - early vascular plexus of foot is supplied by ischiadic artery
         - as this connection regresses, plexus is supplied by posterior tibial;
          - later, new anterior tibial artery  reaches foot & comes to supply dorsal arcuate artery & its branches, & posterior tibial artery
               supplies the plantar arteries.