FEMORAL ARTERY. 



237 



cess of the pubes, and from two and a half to 

 two and three quarters from the superior an- 

 terior spinous process of the ilium. 



The femoral artery is attended through its 

 entire course by the femoral vein, the two 

 vessels lying in apposition and inclosed within 

 a fibre-cellular investment, to which the ap- 

 pellation femoral sheath will be applied. It 

 is also related to the crural nerve or its branches, 

 and it is contained, together with the vein, in 

 a canal of fascia, which will be denominated 

 the femoral canal. 



It is necessary to dwell here, for a little, 

 upon the distinction between the two appel- 

 lations femoral canal and femoral sheath, that 

 a confusion of the one with the other may not 

 arise. The vessels have in fact, throughout 

 their course, two distinct sheaths, which may 

 be considered peculiar to them, contained the 

 one within the other : the external is formed 

 by the fascia lata in a manner to be presently 

 explained, and is in all respects analogous to 

 the canal furnished by the cervical fascia to 

 the carotid artery and jugular vein. This outer 

 sheath, which many may regard as the sheath 

 of the vessels, extends from Poupart's liga- 

 ment to the aperture by which they escape into 

 the popliteal region, and will, for reasons 

 which will appear more fully by-and-bye, be 

 here called t lie femoral canal. The second or 

 internal sheath is situate within the former, 

 is of variable thickness, according to the point 

 at which it may be examined, being for the 

 most part very thin; adheres in general closely 

 to the vessels, in which particular it differs from 

 the outer one, within which they are com- 

 paratively free ; and not only covers, but also 

 separates them by a thin internal process, 

 which by its density and intimate adhesion to 

 the vessels connects them straitly to each 

 other; it is further not confined, as the other is, 

 to the vessels, while called femoral, but is 

 prolonged upon them into the popliteal region, 

 where in like manner it invests and connects 

 them: to this investment the denomination 

 femoral sheath will be applied. A distinction 

 between the two structures is necessary in a 

 description of the relations of the femoral 

 artery, were it only to mark their existence, 

 but that which I have adopted is rendered 

 imperative by the use already made of the 

 latter appellation with reference to the anatomy 

 of hernia, in the history of which it is ap- 

 plied not to the canal as formed by the 

 fascia lata, but to that, through which the 

 femoral vessels escape from the abdomen, and 

 as formed by the fasciae transversalis and 

 iliaca; and the prolongation of the former of 

 these two fasciae being, in my opinion, con- 

 tinued into the internal and immediate in- 

 vestment of the vessels, it has appeared to me 

 justifiable to extend the signification of the 

 title femoral sheath, and to apply it to that 

 investment throughout their entire course, as 

 well below as above the saphenic opening of 

 the fascia lata; while his application of the 

 former appellation, femoral canal, is sanc- 

 tioned by Cloquet, by whom it is used in the 

 same sense. 



Beside those which have been already 

 mentioned, the femoral artery has also, 

 during its course, the following general re- 

 lations : posteriorly it corresponds in suc- 

 cession to the psoas magnus, the pectinalis, 

 the adductor brevis, adductor longus and ad- 

 ductor magnus muscles; anteriorly it is, in 

 the first part of its course, not covered by 

 any muscle and is comparatively superficial ; 

 and through the remainder and more exten- 

 sive portion it is covered by the sartorius. 

 Externally it corresponds to the psoas and 

 iliacus, to the sartorius, the rectus, and lastly 

 to the vastus internus muscles; the latter of 

 which is interposed between it and the inside 

 of the femur: internally it corresponds to 

 the pectinalis and the adductor longus mus- 

 cles ; and lastly it is overlapped by the sar- 

 torius. 



It is contained, through its upper half, in 

 the inguinal region. This region is of a 

 triangular prismatic form, the base of the 

 triangle represented by it being above formed 

 by Poupart's ligament, or by a line connecting 

 the anterior superior spinous process of the 

 ilium and the symphysis pubis; its apex 

 below by the meeting of the sartorius and 

 the adductor longus muscles. The sides of 

 the prism are external and internal, inclined, 

 the former backward and inward, the latter 

 backward and outward, and meeting each 

 other along the internal and posterior side 

 of the femur; they are formed, the external 

 by the iliacus and psoas, the rectus, the vastus 

 internus and the sartorius muscles, and the 

 internal by the pectinalis and the adductors. 

 The base of the prism is in front, consisting 

 of the coverings of the space. During its 

 descent from the os innominatum into the 

 inguinal region, the artery generally inclines 

 inward, describing a curve convex out- 

 ward ; and hence, as it seems to me, the 

 entire course of the vessel has been assumed 

 to be inward ; but this first curve, when 

 present, is soon compensated by another in 

 the opposite direction. In its lower half the 

 artery is enclosed between muscles, the vastus 

 internus upon its outside, the adductors longus 

 and magnus behind it, and the sartorius in 

 front. 



The course of the femoral artery may be 

 advantageously divided into three parts or 

 stages, to be distinguished as first, second, 

 and third, or as superior, middle, and inferior 

 thirds ; in each of which will be found such 

 peculiarities in the relations of the vessel as 

 will justify the number of subdivisions. They 

 may be defined with sufficient precision by 

 dividing the two superior thirds of the thigh 

 into three equal parts, and they will occupy 

 each, according to the stature, from three to 

 five inches. 



The superior stage reaches from Poupart's 

 ligament to the point at which the artery 

 is first covered by the sartorius : during this, 

 its upper third, the vessel is not covered by 

 muscle, except at its termination, where it 

 is overlapped by the inner margin of the 

 sartorius : it is therefore comparatively super- 



