The Leg. 375 



Fibular Muscles. Peroneus longus. From the 

 head and upper two-thirds of the outer surface of the 

 fibula. This muscle passes down behind the outer malle- 

 olus, then on the outer side of the os calcis, and then, 

 changing its course to the under surface of the cuboid, is 

 inserted into the outer side of the base of the metatarsal 

 bone of the great toe and into the internal cuneiform bone. 

 Action. It extends the foot at the ankle joint ; abducts its 

 anterior part, and raises up the outer border, and, in ad- 

 dition, assists in maintaining the arches of the foot. Its ac- 

 tion is seen in walking, in which, along with the muscles 

 forming the tendo Achilles, it raises the heel, and, counter- 

 acting the tendency of these muscles to invert the inner 

 border of the foot, balances, evenly, the foot in the act 

 of walking. 



Peroneus brevis. From the lower two-thirds of the 

 external surface of the fibula; into the outer side of the 

 base of the metatarsal bone of the little toe. Action. 

 To extend, slightly, the foot ; to abduct its anterior part, 

 and to raise up its outer border. Nerves. Having the 

 same action, as the above, it is supplied by the same nerve, 

 viz., the musculo-cutaneous. 



Fractures of the bones of the leg. Tibia. The 

 head of the tibia may be fractured, implicating the joint, 

 or, the epiphysis, which unites with the shaft about the 

 twentieth year, may be separated, or, the tubercle, which, 

 though usually included in the epiphysis, occasionally has 

 a separate centre of ossification, may be torn from the 

 bone. The shaft may be broken from falls on the feet or 

 from direct injury, or the lower epiphysis which unites 

 with the shaft about the eighteenth year, may be torn off. 

 The displacement in fractures of the shaft is very little 

 affected by muscular action, since the unbroken fibula pre- 

 vents any overriding. Fibula. The head of this bone is 



