ioi THE ANATOMY OF THE HORSE 



THE DEEP MUSCLES OF THE ILIO-FEMORAI 



REGION 



Four small muscles attach the fussa uf the trochanter major to tho 

 pelvis, and rotate the femur outwards. 



PvRiFOKMis. — Orujin — from the transverse processes of the sacrum, and 

 the internal face of the ilium by fleshy fi])res, which are inserted into tho 

 trochanteric fossa. Action — to rotate the femur outwards. 



Obturator externus and internus are attached, one to the outside and 

 the other to the inside of the margins of the obturator foramen, and to 

 the two faces of tlie fascia which fills it up. Insertion — by separate 

 tendons into the trochanteric fossa. 



Gemini arise by two bundles of fibres from the supero-postcrior part 

 of the ischium. Insertion — to the trochanteric fossa. Action — the same as 

 the three last-named muscles. 



ANTERIOR FEMORO-CRURAL REGION 



Extensor pedis lies superficially on the anterior part of the leg. 

 Orifjin — from a depression on the anteroinferior and external part of the 

 external condyle of the femur. Insertion — to the coronal process of the os 

 pedis. Action — to flex the hock and extend the foot. 



Peroneus lies on the antcro-extcrnal side of the leg. Origin — from 

 the head of the fibula and outer part of tho tibia. Insertion — to the 

 supero-anterior part of the os suffraginis. Action — to assist the foregoing 

 muscle. 



Flexor metatarsi is situated on the antcro-internal side of the leg. 

 Origin — in common with the extensor pedis, from the outer condyle of 

 the femur, and from the upper part of the anterior face of the tibia. 

 Insertion — to the os cuboidcs and to the large and small metatarsal bones. 

 Action — to flex the hock. 



POSTERIOR FEMORO-CRURAL REGION 



Gastrocnemius externus lies along the posterior part of the leg. 

 Origin — in two portions from the fossa just behind and above each condyle 

 of the femur. Insertion — to a depression on the centre of the point of the 

 OS calcis. Action — to elevate the point of the hock, and thus to extend 

 the leg. 



Gastrocnemius internus is situated on the postero-mesian part of the 

 leg. Origin — from the inner part of the ridge which surrounds tho fossa 

 behind and between the two condyles of the femur. Insertion — above 

 the hock it becomes tendinous, and passes over the point (from which it is 

 separated by a large bursa mucosa, the seat of capped hock), and descends 

 along the back of the flexor tendons, where it corresponds with tlie flexor 



