216 ANATOMY IX A NUTSHELL. 



lies upon the l>ack of the ischium, the nerve to Quadratus femoris. the Gemelli 

 muscles, Obturator interims. Quadratus femoris. and Adductor magnus muscles. 

 It i- accompanied by the sciatic artery and the small sciatic nerve. In the 

 tipper part of its course it is covered by the Gluteus maximus and in its lower 

 part by the long head of the Biceps. Before it divides it gives, (a) articular 

 branches t<> the hip-joint which perforates the capsular ligament posteriorly. 

 (b) MUS< ri. ak branches beneath the long head of the Biceps to the Biceps. 

 Semitendinosus, Semimembranosus, and Adductor magnus. The fibers in the 

 internal popliteal or popliteal are from the fourth and fifth Lumbar, first, second. 

 ami third sacral. (Plate LXXVII.) This is the larger of the two divisions, 

 it passes through the popliteal space. At the lower border of the Popliteus 

 muscle it is called the posterior tibial nerve. It is like the median nerve of 

 arm in that it lies at first on the outer side of the artery, then crosses it to lie 

 on its inner side. It gives off the following branches. (1) articular branches 

 to the knee-joint which are three in number: first, superior internal; second, 

 superior external, and third, azygos. 



(2) Muscular branches to the Gastrocnemius. Plantaris, Popliteus. and 

 Soleus. 



(3) Communicans poplitei which joins the communicans peronei to form 

 the short saphenous nerve, which supplies integument on the posterior part of 

 the Leg and on the outer side of the foot. (4) This nerve continues as the 

 posterior tibial after it passes the lower border of the Popliteus muscle. The 

 posterior tibial nerve crosses the posterior tibial vessels from within out. just the 

 opposite from the median and popliteal nerves. (Plate LXXVIII.) In the 

 lower part of the leg these posterior tibial vessels and the nerve lie parallel with 

 the inner border of the tendo Achillis. The branches of this nerve are. (1) mus- 

 cular to the Soleus. Tibialis posticus. Flexor longus hallucis. Flexor longus 

 digitorum. (2) Internal calcanean (cutaneous) which passes with the in- 

 ternal calcaneal) artery. It supplies the integument and fascia of the heel and 

 a part of the sole. (3) Articular branches to the ankle. (4) Internal 

 axd external plantar nerves, which are formed by the division of the pos- 

 terior tibial nerve at a point midway between the internal malleolus and inner 

 tubercle of the os calcis. These nerves accompany the internal and external 

 arteries. While the internal plantar nerve islarger than the external plantar, the 

 arteries are just the reverse. the external being Larger than the internal. The in- 

 ternal nerve supplies the following five muscles. (1) Abductor hallucis, (2) Flexor 

 brevis digitorum, (3) and (4) the two inner Lumbricales. (5) Flexor brevis 

 hallucis. It also supplies integument on the inner aspect of the plantar sur- 

 face of the fo«.t. (Plate LXXXI.) The external plantar nerve supplies the 

 following fourteen muscles. (1) Abductor minimi digiti, (2) and (3) the two 

 outer Lumbricales, (4) Flexor accessorius, (5) Flexor brevis minimi digiti. the 

 seven [nterossei make twelve. (13) the Adductor transversus hallucis. and 



1 I the Adductor obliquus hallucis. This nerve also supplies integument on 

 the plantar surface of the foot. 



