648 



HUMAN ANATOMY. 



peroneal tendons to be attached to the tuberosity of the same bone. The otner 

 band, the internal an^iular ligament (ligamentum laciniatum) passes downward and 

 backward from the inner malleolus to the calcaneum, bridging over a groove which 

 is divided into four compartments by partitions extending from the ligament to the 

 subjacent bone. The innermost of these compartments is occupied by the posterior 

 tibial muscle ; the second one contains the tendon of the flexor longus digitorum ; 

 the third, the posterior tibial vessels and nerve ; and the outermost, the tendon of 

 the flexor longus hallucis. 



From the deep surface of that portion of the crural fascia which covers the 

 peroneus longus and brevis two strong expansions of connective tissue pass deeply, 



Fig. 617. 



Anterior tibial arten.- 

 Anterior tibial nerve 



Extensor longus digitorum 



Musculo-cutaneous nerv( 



Extensor longus halluci 



Peroneus longus. 

 Peroneus brevi 

 Fibula, 

 Extern, intermuscular septum. 



Flexor longus hallucis 

 Peroneal vesseli 



Deep fascial septum 



Gastrocnemius, outer hea 



Tibialis anticus 



Interosseous membrane 



Tibia 



Tibialis posticus 



Flexor longus digitorum 



Internal saphenous vein 



Posterior tibial vessels 

 Internal saphenous nerve 

 Posterior tibial nerve 



■Soleus 



Tendon of plantaris 

 Gastrocnemius, inner head 



Deep fascia 



Skin Superficial fascia 

 Section across right leg at junction of upper and middle thirds, viewed from below. 



one in front of and one behind the muscles, to be attached to the fibula. These are 

 the anterior and posterior i?itermuscular septa ; they serve for the origin of portions 

 of the adjacent muscles. 



In regions in which the crural fascia is adherent to subjacent bony structures a 

 number of subcutaneous bursa occur between the deep fascia and the integument. 

 Thus, over the patella there is usually to be found a bursa (bursa prepatellaris sub- 

 cutanea) ; occasionally one (bursa prepatellaris subfascialis) occurs between the 

 patella and the fascia. Another (bursa infrapatellaris subcutanea) frequently lies over 

 the ligamentum patellae, and immediately below it the bursa subcutanea tuberositatis 

 tibiae. Again, over each malleolus a bursa often exists (bursae malleoli lateralis et 

 medialis) ; finally, a bursa frequently occurs over the tendo Achillis at its insertion 

 into the tuberosity of the calcaneum (bursa subcutanea tendinis calcauei). 



{a) THE PRE-AXIAL MUSCLES. 



As is the case with the antibrachial pre-axial muscles, those of the crus are 

 primarily arranged in three layers, the most superficial sheet being attached above 

 to the condyles of the femur, for the most part to the outer one. A further simi- 

 larity to the arrangement in the forearm is to be found in the continuation of the 

 muscles of the middle layer into the foot, to act as flexors of the digits. 



