1 66 HEAD AND NECK 



vertebrae, and the supraspinous ligaments between them. 

 The dissector will note, however, that this is not an indepen- 

 dent and distinct attachment, but that it is effected through 

 the medium of the lumbo- dorsal fascia, with which the 

 aponeurotic tendon of the muscle blends. The muscle 

 passes upwards and laterally and is inserted into the outer 

 surfaces of the lower four ribs. 



Fascia Lumbo-dorsalis. On the third day after the body 

 is placed upon its face the dissector of the head and neck 

 should associate himself with the dissector of the abdomen 

 in the examination of the lumbo-dorsal fascia. It is an 

 aponeurotic layer, thin in the thoracic portion of its extent, 

 but thick and strong in the lumbar and sacral regions ; and 

 in all these regions it binds down the muscles of the back 

 to the sides of the spinous processes and to the transverse 

 processes of the vertebrae. 



The Dorsal Part of the Lumbo-dorsal Fascia (O.T. Vertebra,, 

 Aponeurosis]. This part of the lumbo-dorsal fascia is a thin 

 transparent lamina which extends from the tips of the spines 

 and the supraspinous ligaments to the angles of the ribs. 

 At the upper end of the thoracic region it dips beneath the 

 serratus posterior superior into the neck, and at the lower 

 end it blends with the aponeurosis of origin of the serratus 

 posterior inferior, and through that becomes continuous with 

 the posterior layer of the lumbar portion. 



Dissection. To display the lumbar part of the lumbo-dorsal fascia clear 

 away the remains of the origin of the latissimus dorsi, which springs from 

 its posterior surface, and then reflect the serratus posterior inferior by 

 cutting through it at right angles to its fibres and turning it medially and 

 laterally towards its origin and insertion. As the lateral part is turned 

 aside secure its nerves of supply, which are derived from the lower inter- 

 costal nerves, and enter its deep surface. Next remove the remains of the 

 origin of the serratus posterior inferior, and then the posterior layer of the 

 lumbar part of the lumbo-dorsal fascia will be completely exposed. 



The Lumbar Part of the Lumbo-dorsal Fascia. This portion 

 of the lumbo-dorsal fascia is separable into three lamellae, a 

 posterior, a middle, and an anterior. All three fuse together 

 laterally, where they become connected with the internal 

 oblique and the transversus abdominis muscles. The posterior 

 layer, which is the strongest of the three, is a dense tendinous 

 aponeurosis. It is continuous above with the thoracic part. 

 Below, it is attached to the posterior part of the lateral lip of 

 the iliac crest, and to the dorsum of the sacrum and the coccyx. 



