272 THE ARTICULATIONS, OR JOINTS 



highly elastic property serves to preserve the upright posture and to assist in 

 resuming it after the spine has been flexed. These ligaments do not exist 

 between the occiput and atlas or between the atlas and axis. 



3. LIGAMENTS CONNECTING THE ARTICULAR PROCESSES. 

 Capsular Ligaments. 



The capsular ligaments (capsulae articulares) (Fig. 224) are thin and loose 

 ligamentous sacs, attached to the contiguous margins of the articulating processes 

 of each vertebra through the greater part of their circumference, and completed 

 internally by the ligamenta subflava. They are longer and looser in the cervical 

 than in the thoracic or lumbar regions. The capsular ligaments are lined on 

 their inner surface with synovial membrane. 



4. LIGAMENTS CONNECTING THE SPINOUS PROCESSES. 



Supraspinous Ligament. 

 Ligamentum Nuchae. 

 Interspinous Ligaments. 



The Supraspinous ligament (ligamentum supraspinale (Fig. 222) is a strong 

 fibrous cord, which connects the apices of the spinous processes from the seventh 

 cervical to the spinous processes of the sacrum. It is thicker and broader in 

 the lumbar than in the thoracic region, and intimately blended, in both situa- 

 tions, with the neighboring aponeurosis. The most superficial fibres of this 

 ligament connect three or four vertebrae; those deeper-seated pass between two 

 or three vertebrae; while the deepest connect the contiguous extremities of neigh- 

 boring vertebrae. It is continued upward to the external occipital protuberance 

 as the ligamentum nuchae. 



The ligamentum nuchae is a fibrous membrane which, in the neck, represents 

 the Supraspinous ligaments of the lower vertebrae. It extends from the external 

 occipital protuberance and crest to the spinous process of the seventh cervical 

 vertebra. From its anterior border a fibrous lamina is given off, which is attached 

 to the posterior tubercle of the atlas, and to the spinous processes of all the cervical 

 vertebrae, so as to form a septum between the muscles on either side of the neck. 

 In man it is merely a rudiment of an important elastic band w r hich, in some of 

 the lower animals, serves to sustain the weight of the head. 



The interspinous ligaments (ligamenta interspinalia) (Fig. 222), thin and 

 membranous, are interposed between the spinous processes. Each ligament 

 extends from the root to the summit of each spinous process and connects their 

 adjacent margins. They meet the ligamenta subflava in front and the supraspin- 

 ous ligament behind. They are narrow and elongated in the thoracic region; 

 broader, quadrilateral in form, and thicker in the lumbar region; and only slightly 

 developed in the neck. 



5. LIGAMENTS CONNECTING THE TRANSVERSE PROCESSES. 

 Intertransverse Ligaments. 



The intertransverse ligaments (ligamenta intertransversaria) (Fig. 235) consist 

 of bundles of fibres interposed between the transverse processes. In the cervical 

 region they consist of a few irregular, scattered fibres; in the thoracic, they are 

 rounded cords intimately connected with the deep muscles of the back; in the 

 lumbar region they are thin and membranous. 



