238 ANATOMY OP THE LOWER EXTREMITY. 



termination of the external saphena nerve, which supplies 

 the little toe, and sometimes the outer side of the next. 

 The distribution of the nerves to the toes constantly varies. 

 The fascia of the leg, extending across from the anterioi 

 surface of the tibia to the fibula, is extremely dense, and, 

 at the upper part of the leg, binds down and is closel; 

 adherent to the muscles beneath, some of their fibres 

 originating from it. At the ankle, it- forms the anterioi 

 annular ligament; this is a thickened portion, crossing 

 from the external malleolus and upper surface of the os 

 calcis to the internal malleolus, and the borders of which 

 are imperfectly defined ; it contains three sheaths for the 

 tendons of the muscles which pass down from the leg to 

 the dorsum of the foot, viz., one for the tibialis anticns, 

 one for the extensor proprius pollicis, and the third for the 

 extensor longus digitorum and peroneus tertius muscle. 

 The under portion of the sheath for the extensor proprius 

 pollicis muscle converts that part of the ligament into a 

 sort of sling, and is attached to the os calcis under the 

 name of ligament of Retzius. 



The fascia of the leg should be removed by detaching it from below 

 upward ; where it becomes blended with the bellies of the muscles, it 

 should be left in connection with them. The annular ligament is not 

 to be removed. The muscles of this region should be separated from 

 each other by following them up from their tendons. 



The TIBIALIS ANTICUS MUSCLE lies along the side of the 

 tibia, arising from the upper two thirds of its inner surface 

 and from the interosseous membrane ; its tendon passes 

 through a separate sheath in the annular ligament, and is 

 inserted into the side of the internal cuneiform bone and 

 the head of the first metatarsal bone. 



The EXTENSOR PROPRIUS POLLICIS is a thin muscle, 

 covered in by the tibialis anticus on one side and the 

 extensor longus digitorum on the other ; it arises from the 

 middle third of the fibula, and its tendon, which runs along 

 the anterior border of the muscle, receiving the fibres in a 

 penniform manner, passes through a separate sheath in the 

 annular ligament, and is inserted into the base of the second 

 phalanx of the great toe. 



The EXTENSOR LONGUS DIGITORUM arises from the upper 

 half of the fibula, from the head of the tibia and from the 

 interosseous membrane ; its fibres are inserted in a penni- 

 form manner into three tendons which commence upon the 



