DISSECTION OP THE POSTERIOR LIMB. 



77 



hock it is directed obliquely forward, and joins the tendon of the 

 extensor pedis about the middle of the metatarsus. 



Action.- — The same as the preceding muscle. 



Directions. — Cut the extensor pedis about the middle of the leg, and 

 reflect it upwards and downwards to expose the next muscle. 



The Flexor Metatarsi (Fig. 3). This muscle consists of two parallel 

 portions — a superficial and a deep. The superficial division exists in 

 the form of a tendinous cord with little or no 

 muscular tissue, and arises, in common with the 

 extensor pedis, from the pit between the trochlea 

 and external condyle of the femur. This tendon 

 of origin passes through the notch between the 

 anterior and external tuberosities at the upper 

 end of the tibia, and is there enveloped by the 

 synovial membrane of the femoro-tibial joint. 

 In the leg the tendinous cord rests on the deep 

 division of the muscle, and passes under the 

 annular band at the lower extremity of the tibia, 

 in company with the tendon of the extensor 

 pedis. At the front of the hock it is perforated 

 by the tendon of the deep division, and then 

 bifurcates, one branching continuing downwards 

 to be inserted into the upper extremity of the 

 . large metatarsal bone, the other deviating out- 

 wards to be inserted into the cuboid. 



The deep division of the flexor metatarsi rests 

 on the tibia, and its muscular fibres arise from 

 the upper part of the outer surface of that bone. 

 At the lower end of the tibia it is succeeded by 

 a tendon which perforates that of the superficial 

 division of the muscle, and divides, one branch 

 passing to be inserted into the head of the large 

 metatarsal bone, along with the large division 

 of the superficial cord, while the other branch is 

 carried inwards to be inserted into the cuneiform 

 parvum. 



Action. — To flex the hock. In this action 

 the superficial tendinous cord plays merely a 

 mechanical part, flexing the hock when the 

 stifle is flexed. 



The External Popliteal Nerve (Plate 18). 

 This nerve has already been seen in the hip and 



thigh. It is a branch given oS by the great sciatic ; and, descending 

 in front of the parent nerve, it passes between the biceps and the outer 



Fig. 3. 



Flexor Metatarsi Muscle 

 (Chauveau). 



1. Sixperficial division of 

 the muscle ; 2. Its origin 

 from the femur ; 3. Its 

 cuboid branch ; 4. Its meta- 

 tarsal branch ; 5. Deep 

 division of the muscle ; (i. 

 Its tendon passing through 

 that of the superiicial 

 division ; 7. Cuneiform 

 branch of this tendon ; S. 

 Metatarsal branch of the 

 same ; 9. Extensor pedis ; A. 

 Peroneus ; B. Insertion of 

 middle straight patellar liga- 

 ment ; C. Femoral trochlea. 



