370 



PRACTICAL ANATOMY. 



THE GLUTEAL REGION. 



The gluteus maximus muscle (Eig. 256) must now be put on the stretch 

 by rotating the entire limb inward, and at the same time drawing the subject to 

 the edge of the table and slightly lowering the leg. Now, with a sharp scalpel 

 remove the deep fascia from the muscle itself (Fig. 257), and locate the line of 

 differentiation between the gluteus maximus and medius. Theoretically, this is 

 easily done, but practically some experience is necessary to obtain perfect results, 

 since the gluteal aponeurosis continues forward and completely covers the gluteus 

 medius muscle. The gluteus maximus originates : (i) From the aponeurosis of 

 the gluteus medius ; (2) from the lumbar aponeurosis and the greater sacro-sciatic 

 ligament ; (3) from the side of the coccyx ; (4) from the back of the lateral part 



FIG. 257. GLUTEUS MAXIMUS MUSCI.K. 

 I. Gluteus maximus. 2. Its inferior portion. 3. Fibres of attachment to linea aspera. 4. Superior 

 portion. 5, 5. Tendinous fibres of insertion into linea aspera. 6. Upper portion of femoral apo- 

 neurosis. 7. Duplicature of this aponeurosis at superior level of gluteus maximus. 8. Portion of 

 its superficial layer attached to tendinous bands. 9. Lower extremity of tensor vaginae femoris. 



10, IO. Portion of femoral aponeurosis continuous with tendinous fibres of gluteus maximus. 



11. Upper portion of biceps femoris. 12. Upper portion of semitendinosus. 13. Upper portion of 

 seminiembranosus. 14. Gracilis. 



of the lower two segments of the sacrum ; (5) from the posterior one-fifth of the 

 outer lip of the iliac crest ; (6) from the surface of the bone between the crest of 

 the ilium and the superior gluteal ridge. ( l ; ig. 226.) The muscle is inserted 

 into: (i) The ilio-tibial band; (2) into the gluteal ridge of the femur. (Fig. 

 227.) The inferior gluteal nerve, a branch of the sacral plexus, supplies this 

 muscle. 



Cut at its insertion into the deep fascia of the thigh, and into the gluteal 

 ridge of the femur, the gluteus maximus ; turn tin- same back, as seen in figure 

 258. Also cut the insertion of the gluteus medius at the oblique line of the 

 greater trorhanter (Fig. 227), turn same up. and develop your work like 

 figures 258 and 259. Caution! Take the greatest care, in turning the 



