THE LIMBS OF THE HORSE 109 



Dissection. — The removal of the deep fascia is tedious, and more 

 particularly so over the gluteal muscles. The dissector will be well 

 advised to begin its removal just distal to the level of the hip joint 

 and work in a proximal direction. The fascia lata should not be 

 interfered with until its tensor muscle has been examined. 



M. TENSOR FASCIA LAT^.— The tensor of the fascia lata has a com- 

 paratively restricted origin from the coxal tuber of the ilium ; but, in 

 addition, some fibres spring from an intermuscular septum that is 

 adherent to the lateral border of the ilium, and from which some of 

 the fibres of the superficial gluteal muscle arise. From this origin the 

 fibres of the muscle spread out in fan-like manner, to merge into the 

 fascia lata and the fascia of the leg. Through its fascial connections 

 the muscle may be regarded as having indirect insertions to the patella, 

 the most lateral of the three patellar ligaments, and the crest of 

 the tibia. 



Dissection. —The fascia lata should now be cut across about the middle 

 of the thigh and transverse to the long axis of the limb. Its tensor 

 should then be turned forwards as far as possible. 



M. GLUTEUS suPERFiciALis.^Tlie Superficial gluteal i muscle consists 

 of two fleshy parts that converge and blend towards the insertion of 

 the muscle into the third trochanter of the femur. The lateral portion 

 of the muscle arises from the coxal tuber of the ilium in common with 

 the tensor fasciae latse, from the lateral border of the ilium in the 

 neighbourhood of the coxal tuber, and from the intermuscular septum 

 between the gluteal muscle and the tensor fascise latte. The medial part 

 takes origin from the gluteal fascia not far from the sacral tuber of 

 the ilium. 



M. BICEPS FBMORis. — The very powerful and thick biceps muscle has 

 a double origin. One head arises from the spinous processes of the third, 

 fourth, and fifth sacral segments, the short dorsal sacro-iliac ligament, 

 the coccygeal and gluteal fascise, and the sacro-tuberous ligament. The 

 other head is tendinous, and has origin from the sciatic tuber. The two 

 heads combine to form a single muscular mass that soon divides into 

 three parts. (1) The most anterior portion is the strongest, and, by 

 means of an aponeurotic tendon, is inserted into the patella and the 

 most lateral of the three bands that represent the patellar ligament. It 

 is also connected, by a flattened tendinous band, with the femur behind 

 and immediately distal to the third trochanter, where a synovial bursa 

 lies between the tendon and the bone. (2) The aponeurotic tendon of 

 the middle portion of the muscle is attached to the crest of the tibia 

 and the fascia of the leg. (3) The posterior part of the biceps also is 

 connected with the fascia of the leg, and, by means of a stout band 



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