230 ANATOMY OF THE tioWER EXTREMITY 



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ing in the direction of its fibres. The skin is thick and tongh, and 

 there is a deep layer of fat beneath it, which will probably be found 

 more or less infiltrated with the fluids which have gradually gravitatec 

 into the part while dependent. 



The glutens maximus, which is the first muscle expose 

 is composed of coarse bundles of fibres, between whicl 

 penetrate prolongations from its sheath. It is one of the 

 most difficult muscles in the body to dissect neatly, though 

 in a favorable subject, and when well dissected, few present 

 a more showy appearance. 



The GLUTEUS MAXIMUS MUSCLE arises from the posterior 

 fifth of the crest of the ilium, and of the bone beneath, 

 from the lateral tubercles of the sacrum, the sacro-iliac 

 and the greater sacro-ischiatic ligaments, and from the 

 side of the coccyx ; its upper half is inserted into a thick, 

 flat tendon, covering in the greater trochanter and con- 

 tinuous with the fascia lata of the thigh ; the lower portion 

 is inserted into the rough line on the femur, leading from 

 the trochanter major to the linea aspera. Beneath this 

 broad tendon is a large S3 r novial bursa. The upper border 

 of this muscle is closely adherent to the aponeurotic ex- 

 terior of the glutens medius muscle, by means of the fascia 

 lata ; its lower border forms the fold of the nates, and 

 overlaps the origins of the muscles of the back of the thigh. 



This muscle is to be divided transversely, and its two ends are to 

 be reflected ; this will expose the gluteus medius. 



In dividing the gluteus maximus, a number of arterial 

 twigs, distributed to the muscle, will be cut across ; they 

 are muscular branches of the gluteal and ischiatic arteries; 

 a few ascending twigs from the external circumflex will 

 also be seen. 



The LESSER SCIATIC NERVE, coming from the sacral 

 plexus, emerges with the ischiatic artery at the sacro-ischi- 

 atic foramen. Its branches supply the integument and 

 the gluteus maximus, which it penetrates at its lower 

 border ; some of its branches descend and are distributed 

 upon the posterior aspect of the thigh ; one of these, larger 

 than the others, is called the middle posterior cutaneous 

 nerve. 



The GLUTEUS MEDIUS MUSCLE, partially covered by the 

 gluteus maximus, and elsewhere by a dense aponeurosis, 

 which cannot be dissected from the muscular tissue beneath, 

 arises from the anterior four fifths of the crest of the ilium, 



