Labio-glossal Paralysis j\ 



the spinal accessory is the nerve of phonation. As the spinal and the 

 accessory parts of the eleventh nerve pass through the jugular foramen 

 they interchange filaments, and thus it is that the sterno-mastoid 

 and trapezius are in direct association with the muscles of the vocal 

 cords. 



Peripheral or central irritation of the spinal part of the nerve may 

 cause spasmodic or tonic contraction of the sterno-mastoid and 

 trapezius ; rhythmic contraction and relaxation of those muscles of the 

 two sides cause the nodding movement so often seen in old persons 

 nodding palsy. 



Stretching, or partial resection, of the spinal accessory nerve may 

 be needed in certain aggravated cases of spasmodic contraction of the 

 sterno-mastoid. The nerve is sought as it runs beneath the anterior 

 border of the muscle, previous to piercing it, about two inches below 

 the mastoid process. The incision is made through skin, platysma, 

 and fasciae for about three inches along the front of the muscle, down- 

 ward from the mastoid process. The muscle is then relaxed by rais- 

 ing the head, and, its anterior border having been drawn outwards, the 

 nerve is seen entering it. 



No. 12. The hypoglossal is the motor nerve of the tongue; it 

 arises in the floor of the fourth ventricle, and emerges from the groove 

 between the anterior pyramid and olive, that is, in the line of the 

 motor roots of the cervical nerves. It leaves the skull through the 

 anterior condylar foramen, and descends with the vagus, between the 

 internal jugular vein and the carotid artery, to the level of the angle 

 of the jaw, when it passes forwards, over the internal and external 

 carotids, and over the hyo-glossus; then, sloping upwards beneath the 

 posterior tendon of the digastric, and under the mylo-hyoid, it ends in 

 the genio-hyo-glossus. It supplies also the stylo- and hyo-glossus, the 

 genio-hyoid, and, by a special branch, the thyro-hyoid. 



It gives off the descendens hypoglossi (or descendens noni, when the 

 motor linguae is reckoned as the ninth nerve), which, joined by a com- 

 municating loop from the second and third cervical nerves, supplies the 

 depressors of the hyoid bone. This nerve lies upon the sheath of the 

 common carotid. 



When one of the twelfth pair of nerves is paralysed the genio- 

 hyo-glossus of that side cannot help in the protrusion of the tongue, 

 which it should do by its posterior fibres ; so that, on the patient try- 

 ing to put out his tongue, the tip is carried over to the paralysed 

 side (p. 68). And this paralysed side is weak, flabby, and greatly 

 wasted. 



Duchenne s disease, or glosso-labio-laryngeal, or labio-glosso-pha- 

 ryngeal paralysis, is the result of disease of that part of the medulla from 

 which the facial, glosso-pharyngeal, vagus, spinal accessory, and hypo- 

 glossal nerves arise. Another name for the disease is bulfcar paralysis, 

 because of the degeneration existing in the bulbar part of the cord. 



