1288 



HUMAN ANATOMY. 



Variation. The superficial cervical, instead of a single nerve, may arise as two or more 

 filaments from the cervical plexus. 



The descending branches (nn. supraclaviculares) (Fig. 1089) arise from the 

 third and fourth cervical nerves and pass downward in the anterior margin of the 

 occipital triangle along the posterior edge of the sterno-mastoid. On nearing the 

 clavicle they break up into three distinct sets : (4) the suprasternal , (5) the supra- 

 clavicular and (6) the supraacromial. 



FIG. 1088. 





Third occipital nerve 

 Great occipital nerve 



Branch from III. cervical, 

 dorsal division 



Branches from IV. cer- J 

 vical, dorsal division J 



Inosculation between facial nerve and 

 small occipital and great auricular 

 nerves 



Sterno-cleido-mastoid muscle 



Great auricular nerve 

 Small occipital nerve 



Superficial cervical nerve 



Superficial descending branch of cervical plexus; 

 the leader crosses the suprasternal branch 

 Spinal accessory nerve 

 Muscular branch to trapezius 



raclavicular branches 

 Supraacromial branches 



Dissection showing superficial branches of cervical plexus and posterior cutaneous branches. 



4. The suprasternal branches (rr. supraclaviculares anteriores) are the 

 smallest. They pass over the lower end of the sterno-mastoid and the inner end of 

 the clavicle and supply the skin of the chest as far down as the angulus Ludovici. 

 One or two filaments terminate in the sterno-clavicular articulation. 



5. The supraclavicular branches ( rr. supraclaviculares medii) pass across 

 the middle of the clavicle and supply the integument of the chest as far down as the 

 third or fourth rib, inosculating with twigs from the anterior cutaneous branches of 

 the upper thoracic nerves. 



Variation. A twig may perforate the clavicle. 



