126 LABORATORY MANUAL OF HUMAN ANATOMY 



the Nn. clunium inf eriores in order that they may later be traced 

 to their source. The few coccygeal arteries passing through the 

 ligamentum sacrotuberosum may be sacrificed. The muscle can 

 now be partially reflected, but is still attached by blood-vessels 

 and nerves entering its under surface. These should now be 

 carefully cleaned. Having studied these last structures, they 

 may be cut away, leaving a small piece of muscle connected to 

 each. The whole muscle may then be reflected and its insertion 

 examined. Clean and study the following : 



Bursae. (Vide Spalteholz, Figs. 385, 386.) 



(a) Bursa trochanterica M. glutaei maximi. 



(b) Bursa ischiadica M. glutaei maximi. 



(c) Bursae glutaeofemorales. 



Muscles. 



(a) Gluteus medius muscle (M. glutaeus medius). 



(b) Piriform muscle (M. piriformis). Note the relation it bears to 



the foramen ischiadicum ma jus. 



(c) Tendon of obturator internus muscle (M. obturator internus), pass- 



ing through the foramen ischiadicum minus and having the Mm. 

 gemelli superior and inferior above and below it. 



(d) Quadratus femoris muscle (M. quadratus femoris). 



(e) Smallest adductor muscle (M. adductor minimus) (0. T. upper 



adductor magnus). 

 (/) Tendon of the obturator externus muscle (M. obturator externus). 



Blood-vessels. (Fig. 48.) 



(a) Above the M. piriformis: 



(aa) Superior gluteal artery (A. glutaea superior}. 



(aaa) Upper ramus (ramus superior). 



(aab) Lower ramus (ramus inferior). 



(ab) Superior gluteal veins (Vv. glutaeae superior -es). 



(b) Below the M. piriformis: 



(ba) Inferior gluteal artery (A. glutaea inferior) (0. T. sciatic 



artery). 



(baa) Coccygeal branch, passing inward between the 



greater and lesser sacrosciatic ligaments to reach 

 the integument and fascia in the region of the 

 coccyx. Some twigs derived from this have 

 already been cut in reflecting the muscle. 



(bab) Companion artery of the great sciatic nerve (A. 



comitans N. ischiadici). 



(bac) Artery to the quadratus femoris. This artery will 



serve as a guide for the nerve to this muscle in 

 the further dissection. 



(bb) Inferior gluteal veins (Vv. glutaeae inf eriores). 



(be) Internal pudendal artery (A. pudenda interna). The pudic 

 vessels can be seen emerging from the pelvis through the 

 foramen ischiadicum ma jus and immediately re-enter- 

 ing through the foramen ischiadicum minus. No 



