496 



MYOLOGY 





and the Abductor digiti quinti. The Interossei dorsales are abductors from an imaginary line 

 passing through the axis of the second toe, so that the first muscle draws the second toe medifil- 

 ward, toward the great toe, the second muscle draws the same toe lateralward, and the third 

 and fourth draw the third and fourth toes in the same direction. Like the Interossei in the hand, 

 each assists in flexing the first phalanx and extending the second and third phalanges. The 

 Abductor hallucis abducts the great toe from the second, and also flexes its proximal phalanx. 

 In the same way the action of the Abductor digiti quinti is twofold, as an abductor of this toe 

 from the fourth, and also as a flexor of its proximal phalanx. The adductors are the Interossei 

 plantares and the Adductor hallucis. The Interossei plantares adduct the third, fourth, and 

 fifth toes toward the imaginary line passing through the second toe, and by means of their inser- 

 tions into the aponeuroses of the Extensor tendons they assist in flexing the proximal phalanges 

 and extending the middle and terminal phalanges. The oblique head of the Adductor hallucis 

 is chiefly concerned in adducting the great toe toward the second one, but also assists in flexing 

 this toe; the transverse head approximates all the toes and thus increases the curve of the trans- 

 verse arch of the metatarsus. The flexors are the Flexor digitorum brevis, the Quadratus plants?, 

 the Flexor hallucis brevis, the Flexor digiti quinti brcvis, and the Lumbricales. The Flexor 

 digitorum brevis flexes the second phalanges upon the first, and, continuing its action, flexes the 

 first phalanges also, and brings the toes together. The Quadratus plantae assists the Flexor digi- 

 torum longus and converts the oblique pull of the tendons of that muscle into a direct backward 

 pull upon the toes. The Flexor digiti quinti brevis flexes the little toe and draws its metatarsal 

 bone downward and medialward. The Lumbricales, Like the corresponding muscles in the hand, 

 assist in flexing the proximal phalanges, and by their insertions into the tendons of the Extensor 

 digitorum longus aid that muscle in straightening the middle and terminal phalanges. The 

 Extensor digitorum brevis extends the first phalanx of the great toe and assists the long Extensor 

 in extending the next three toes, and at the same time gives to the toes a lateral direction when 

 they are extended. 



BIBLIOGRAPHY. 



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