514 



THE MUSCLES AND FASCIAE. 



1. Dissection of 

 gluteal region. 



THE HIP. 

 Gluteal Region. 



Gluteus maximus. Gemellus superior. 



Gluteus medius. Obturator internus. 



Gluteus minimus. Gemellus inferior. 



Pyriformis. Obturator externus. 



Quadratus femoris. 



Dissection (Fig. 328). The subject should be turned on its face, a block placed beneath 

 the pelvis to make the buttocks tense, and the limbs allowed to hang over the end of the table, 

 with the foot inverted and the thigh abducted. Make an incision through the integument along 

 the crest of the ilium to the middle of the sacrum, and thence downward to the tip of the coccyx, 

 and carry a second incision from that point obliquely downward and outward to the outer side 

 of the thigh, four inches below the great trochanter. The portion of integument included 

 between these incisions is to be removed in the direction shown in the figure. 



The Gluteus maximus (Fig. 329), the most superficial muscle in the gluteal 

 region, is a very broad and thick, fleshy mass of a quadrilateral shape, which 

 forms the prominence of the nates. Its large size is one of the most characteristic 

 points in the muscular system in man, connected as it is with the power he has of 

 maintaining the trunk in the erect posture. In structure the muscle is remarkably 

 coarse, being made up of muscular fasciculi lying parallel with one another, and 



collected together into large bundles, separated 

 by deep cellular intervals. It arises from the 

 superior gluteal line of the ilium and the por- 

 tion of bone, including the crest, immediately 

 behind it ; from the posterior surface of the lower 

 part of the sacrum, the side of the coccyx, the 

 aponeurosis of the Erector spinae muscle, and 

 the great sacro-sciatic ligament. The fibres 

 are directed obliquely downward and outward ; 

 those forming the upper together with the 

 superficial fibres of the lower portion termi- 

 nate in a thick tendinous lamina, which passes 

 across the great trochanter, and is inserted into 

 the fascia lata covering the outer side of the 

 thigh, the deep fibres of the lower portion be- 

 ing inserted by a tendon into the rough line 

 leading from the great trochanter to the linea 

 aspera between the Vastus externus and Ad- 

 ductor magnus. 



Three synovial bursce are usually found in 

 relation with this muscle. One of these, of 

 large size, and generally multilocular, separates 

 it from the great trochanter. A second, often 

 wanting, is situated on the tuberosity of the 

 ischium. A third is found between the tendon 

 of this muscle and the Vastus externus. 



Relations. By its superficial surface, Avith 

 a thin fascia, which separates it from the sub- 

 cutaneous tissue ; by its deep surface, from 

 above downward, with the ilium, sacrum, coccyx, 

 and great sacro-sciatic ligament, part of the 

 Gluteus medius, Pyriformis, Gemelli, Obturator 

 internus, Quadratus femoris, the tuberosity of 

 po S t F erior^i7w. i88ecti n f lower extremity " the ischium, great trochanter, the origin of the 



Biceps, Semitendinosus, Semimembranosus, 



and Adductor magnus muscles. The gluteal vessels and superior gluteal nerve 

 are seen issuing from the pelvis above the Pyriformis muscle, the sciatic and 



<3 / 3. Back of thigh. 



2. Popliteal space 



4- Back of leg. 



5. Sole of foot. 



