POSTERIOR AXTIBRACHIAL GROUP. 



227 



c- 



FLEXOR PEDIS PERFORATUS. 



{Flexor Subliniis — Bpicondylo-pTialangeus. ) 



(Fig. 81. b.) 



Situated in the posterior region of the 



Ibre-arm, under the flexors of the carpus, 



this muscle is -long, thin, and prismatic, 



its belly being fleshy, with tendinous 



intersections, and extending almost to the 



carpus, where it is succeeded by a long 



tendon, which passes through a synovial 



sheath behind the joint, closed in by the 



posterior annular ligament. Above the 



carpus, the tendon is joined by a broad 



band of fibrous tissue, called the superior 



carpal or superior *' check " ligament, 



which spriogs from the infero-posterior 



surface of the radius, being also attached 



to the antibrachial fascia, and usually to 



the perforans muscle ; below the knee, 



the tendon assists in the formation of a 



synovial sheath for the tendon of the 



flexor perforans. At the fetlock it ex- 

 pands and forms a ring or sheath, through 



which passes the perforans tendon, hence 



the names perforans and perforatus; below 



the pastern joint the tendon divides into 



two. 



Origin. — From the summit of the epi- 



condyle, by a tendon common to it and 

 the perforans. 



Insertion. — To the projecting lateral 

 parts of the os coronse. 



Relation. — Posteriorly with the flexor 

 metacarpi extemus and medius ; anteri- 

 orly with the perforans. Two important 

 synovial sheaths or canals are related 

 with this and the perforans tendon, 

 the carpal and the metacarpb-phalangeal. The first, to which 

 is attached the antibrachial fascia, is formed by the posterior 



Fio. 81. 



Internal view of the deep muscles 

 of the anterior limb, a, Caput par- 

 vum of triceps extensor brachii ; 

 i, Flexor pedis perforatus ; h', Ita 

 tendon ; h" b'", Slips to the phal- 

 anges ; c c, Flexor pedis perforans ; 

 c', Eadialis accessorius ; c", Ulnaris 

 accessorius ; c'", Inferior check liga- 

 ment ; d, Perforans tendon leaving 

 the sheath of oerforatus tendon. 



