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Anatomy of Skeleton 



the Tensor, and the middle curved line runs into the lower of the two divisions : thus the middle 

 line never really reaches the crest, but the very front fibres of medius, at their origin, lie just under 

 cover of the posterior fibres of the Tensor, which otherwise only covers the minimus. The area 

 of Tensor fascias turns down along the outer side of the notch below the superior spine, with its 

 enclosing lines, here lying to the outer side of and behind Sartorius, 



The lines join again below the origin of the muscle, indicating the junction of the two layers of 

 its covering aponeurosis, and this complete layer turns back above and outside the Rectus to form 

 the inferior curved line, the deepest of the gluteal markings. 



We thus have an aponeurotic sheet covering the Glutei and turning deeply round the front 

 margin of Gluteus minimus, forming a sort of septum that divides this group from those in front : 



this will be placed in contact with the outer aspect of the tendon 

 of Rectus, and is pierced by the ascending branch of the external 

 circumflex artery coming from under that muscle to run among 

 the Glutei. The front fibres of the gluteal muscles are attached to 

 this " septum," which is in fact made from their degenerated 

 fibres, and it thus passes with them to the trochanter of the 

 femur : the aponeurotic band that covers the front of minimus is 

 usually strong, and is sometimes termed the ilio-trochanteric band ; 

 this can therefore be placed on the Ilium at the lower front part 

 of the Tensor area. The " septum " being continuous with the 

 aponeurotic layer on the deep aspect of minimus, comes into 

 contact with the capsule and is attached to it : this can sometimes 

 be followed on the bone when the Gluteus minimus is large. 



Below minimus the back of the acetabulum is covered 

 by Pyriformis, and has the great sciatic nerve resting 

 on it. This is soon separated from bone by Obturator 

 internus and gemelli, but the small nerve to Quadratus 

 femoris still lies with its accompanying vessels on bone 

 deep to these, finally passing to the deep aspect of its 

 muscle, superficial to the tendon of Obturator externus . 

 (Fig. 108). The tendon of the internal Obturator turns 

 round the lesser sciatic notch, which is lined by cartilage 

 and a bursa : upper Gemellus has a rounded tendinous 

 origin on the base of the spine above, while lower 

 Gemellus has a linear origin along the top of the 

 tuberosity below, therefore is covered somewhat by the 

 tendon leaving the notch. The spine of the Ischium is 

 crossed by the nerve to Obturator internus, and at its tip 

 by the internal pudic vessels, these separating it from the 



coccygeal branch of the sciatic artery running Ao pierce the great sciatic ligament. 



The small sacro-sciatic ligament is attached toute tip of the spine. 



The External Ischio-Pubic Region (Fig. 104). A few words may be said about 

 the attachments shown in the figure. The bony origin of Obturator externus can 

 usually be made out on the bone with little trouble : observe that it conies well on to 

 the body of the pubis, where its marginal line is fairly well marked. Its tendon, 

 passing under the capsule, covers the surface A, and lies therefore in front of 

 Quadratus femoris. The adductors as a whole, though they arise largely by tendon, 

 do not generally leave recognisable secondary markings, but their origins are as on the 

 plate, and can be placed as follows. Adductor longus is just below the spine, 

 occupying the space between the oblique marking for the sheath of the Rectus and the 

 Obturator externus : it extends down to just below the level of the mid-point of the 

 symphysis, and in its lower half is separated from the Obturator by Adductor brevis. 



FIG. 108. Schemes of gluteal 

 planes arranged round the 

 joint. P. Pyriformis ; Q. 

 Quadratus femoris. Be- 

 tween these is the Obtura- 

 tor internus and Gemelli. 

 A. plane of course of super- 

 ficial division of gluteal 

 artery ; B. plane of small 

 sciatic ; C. plane of great 

 sciatic ; D. plane of nerve 

 to Quadratus. 



