PHYSIOLOGY OF MUSCLES IIQ 



Annular Ligaments 



The tendons which pass from the leg to the foot are kept in 

 place by special ligaments, anterior and lateral, and surrounded by 

 synovial sheaths as in the wrists. 



POINTS. Eversion of the foot, or lifting the medial border, is done by the 

 tibialis anterior. 



Inversion. Or lifting the lateral border, by the peroneus tertius, and 

 peroneus longus. 



Adduction. By deep posterior muscles of the leg. 



Abduction. By lateral muscles of the leg. 



RESUME. 



Observe certain similarities and differences in the extremities. 

 Extension of the elbow is accomplished by the three-headed muscle, 

 the triceps. Extension of the knee requires a powerful four-headed 

 muscle, the quadriceps. 



The great toe is on the medial border of the foot, the thumb is 

 on the lateral border of the hand. This is so because the terms 

 medial and lateral are applied to the pronated position of the lower 

 extremity and the supinated position of the upper extremity. 



In the upper extremity the joints are all flexed in one direction, 

 as though the limb might be rolled up. In the lower extremity 

 they flex and extend alternately, as though the limb were folded 

 back and forth. 



STRUCTURE AND PHYSIOLOGY OF MUSCLES 



A complete muscle is a complicated structure. It consists of: 



First, the essential muscle substance in the muscle cells, p. 83. 



Second, connective tissue wrappings and partitions. 



Third, tendons or aponeuroses, or both. 



Fourth, blood- and lymph-vessels in great abundance. 



Fifth, muscle nerves. 



The connective tissue supports all of the other structures and 

 protects the muscle, preserving its shape and stability. 



The tendons and aponeuroses provide a means whereby the 

 attachment to other organs is kept within a small space. 



EXAMPLE: The biceps of the arm contains many fibers, but the slender 

 tendons of this muscle occupy only small areas upon the surface of the bones. 

 The aponeurosis of that very powerful muscle, the quadriceps femoris, receives 



