HEAD AND NECK 



attached to the tips of the transverse processes of the thoracic and the 

 accessory processes of the lumbar vertebrae, and a lateral row of muscular 

 slips which are inserted into the lower ten ribs, on the lateral sides of their 

 tubercles, and to the transverse processes of the lumbar vertebrae, and to 

 the posterior surface of the middle lamella of the lumbar fascia. 



Longissimus Cervicis (O.T. Transversalis Cervicis). This portion of the 

 longissimus springs from the transverse processes of the upper four thoracic 

 vertebrae, and ; is inserted into the posterior tubercles of the transverse 

 processes of the cervical vertebrae from the second to the sixth inclusive. 



Longissimus Capitis (O.T. Trachelo-mastoid}. The longissimus capitis 

 lies in the neck under cover of the splenius. It arises in common with the 

 longissimus cervicis from the transverse processes of three or four of the upper 

 thoracic vertebrae, and, in addition, from the articular processes of a like 

 number of the lower cervical vertebrae. The narrow fleshy band which results 

 is inserted into the posterior part of the mastoid portion of the temporal 

 bone, under cover of the splenius capitis and sterno-mastoid muscles. 



The Spinalis. This is the most medial, shortest, and weakest of the three 

 columns, and the most difficult to define. Below, it is intimately blended 

 with the longissimus dorsi, but it may be regarded as taking origin by four 

 tendons from the spines of the upper two lumbar and lower two thoracic 

 vertebrae. These end in a small muscular belly, which is inserted by a 

 series of slips into a very variable number of the upper thoracic spines. 

 It is closely connected with the subjacent semispinalis dorsi. 



Spinalis Cervicis. This upward prolongation of the spinalis is not 

 always easy to define. It springs from the spines of the lower four cervical 

 vertebrae and is inserted into the spines of the second, third, and fourth 

 cervical vertebrae. 



Dissection. The occipital artery has already been seen crossing 

 the apex of the posterior triangle (p. 149), and its terminal branches have 

 been dissected as they ramify in the scalp (p. 157). The second part of 

 the vessel, which extends from under shelter of the mastoid process, along 

 the superior nuchal line of the occipital bone, to the point where it pierces 

 the trapezius to become superficial, can now be exposed fully. To effect 

 this, the longissimus capitis (O.T. trachelo-mastoid) must be divided a 

 short distance below its insertion, and, along with the splenius capitis, 

 thrown upwards as far as possible. 



Arteria Occipitalis. The second part of the occipital 

 artery is now displayed. In the region of the mastoid process 

 it is very deeply placed ; indeed, no less than five structures 

 lie superficial to it. These are (enumerating them in order 

 from the vessel to the surface) (i) the origin of the posterior 

 belly of the digastric muscle; (2) the mastoid process; (3) 

 the longissimus cervicis ; (4) the splenius capitis ; and (5) 

 the sterno-mastoid. 1 As the artery runs posteriorly, it very 

 soon emerges from under cover of the first three of these 

 structures, and a little farther on it leaves the shelter of the 

 splenius, and is then covered by the sterno-mastoid alone. 

 Issuing from under cover of the posterior border of that muscle, 



1 It is not uncommon to find the artery at this point of its course between 

 the splenius and the longissimus capitis. 



