130 



REGIONS OF THE LEG. 



rarely occurs. This we conceive to be a ratio- 

 nal and practical explanation of phenomena 

 which are otherwise obscure. 



It seems probable that that most troublesome 

 ulcer, the varicose, is kept up, and the difficulty 

 of its healing produced not by the irritation 

 occasioned by the mere vicinity of the enlarged 

 veins, but from the actually varicose state of 

 the capillaries of the skin at that part ; at least 

 we have found such a state of the vessels fre- 

 quently, if not generally, to co-exist with this 

 species of ulcer. The depth of the cellular 

 layer (superficial fascia) in which these veins 

 lie should be accurately understood and borne 

 in mind in performing the operation of passing 

 a needle under the vein for the cure of varices, 

 according to Velpeau's plan (a method which 

 we have adopted with considerable success.) 

 Should the needle be passed so deep as to 

 reach the fascia, the inflammation would pro- 

 bably be severe, at any rate sufficient to com- 

 plicate needlessly the operation. The thickness 

 of the cellular layer varies in different subjects, 

 according as it is distended more or less with 

 fat or with accidental effusion ; it is rarely, 

 however, less than two lines in depth, thus 

 affording abundance of room for the transmis- 

 sion of the needle. 



The size of these veins of the leg in the 

 healthy state is at the most not larger than a small 

 goose-quill, but when varicose they sometimes 

 swell to the size of the finger, and we lately 

 saw a varicose enlargement of the saphena 

 major a little below the knee, of the size of a 

 large hen's egg ; the quantity of blood that may 

 in a short time be lost from them may hence be 

 conceived. On the anterior region the veins 

 are few, and varices but rarely occur compara- 

 tively. On the inner region the saphena major 

 lies close upon the bone in part of its course, 

 and even indents it deeply when distention has 

 continued long. In cutting upon the vein in 

 this situation, we must bear in mind the conti- 

 guity of the internal saphenus nerve, whose 

 situation, with relation to the vein, varies much, 

 sometimes being before, sometimes behind it. 

 We cannot, therefore, lay down any rule for its 

 avoidance, unless it be to open the vein parallel 

 to its length. The saphena minor has a nerve 

 running with it, which in phlebotomy must be 

 avoided with the same precaution as the nerve 

 on the inner side. 



The two nerves found imbedded in this su- 

 perficial layer of the leg are, 1st, the internal 

 saphenus, which is the largest, and is passing 

 from the inner side of the knee to the inner 

 side of the foot, accompanying the saphena 

 major vein; 2d, the external saphenus or com- 

 inunicans tibialis from the tibial nerve, which 

 runs near the saphena minor through the lower 

 part of its course. 



Imbedded in the superficial fascia, we also 

 find a set of lymphatics, principally on the 

 inner side of the leg, receiving part of those 

 from the sole and dorsum of the foot, while 

 those absorbents which accompany the sa- 

 phena minor are receiving their commence- 

 ment entirely from the sole of the foot. All 

 of these superficial lymphatics ascend to the 



inner side of the thigh, and terminate in the 

 inguinal glands. Hence diseases of the sub- 

 cutaneous cellular tissue of the leg exert their 

 influence upon the superficial glands of the 

 groin, and are not unfrequently the cause of 

 disease in them, which, without due inquiry, 

 might erroneously be attributed to disease of 

 the genital organs. 



The aponeurosis. of the leg forms an important 

 part of its economy. It is a dense tendinous 

 structure, which immediately invests the mus- 

 cles, and partly affords them origin. In conse- 

 quence of its strength and want of elasticity, it 

 prevents swelling in deep-seated inflamma- 

 tions, and we are consequently obliged to 

 divide it early and freely, particularly when 

 suppuration already exists, and when the mat- 

 ter would otherwise burrow among the muscles. 

 On the anterior region it is strong, very dis- 

 tinct, and tense. In its superior fifth, it gives 

 attachment to the fibres of the tibialis anticus, 

 extensor communis digitorum, and peroneus 

 longus. Below, it is pierced by the anterior 

 tibial and musculo-cutaneous nerves. It is 

 attached above to the heads of the tibia and 

 fibula, and along the crest of the tibia, 

 stretching from this to the anterior edge of the 

 fibula. At the upper third of the leg, it sends 

 processes backwards between the muscles, to 

 be attached to the bones, thus forming sheaths 

 for the muscles, and affording to their fibres a 

 greater extent of origin. At the lower two- 

 thirds of the leg, the fascia is closely attached 

 to the intermuscular tissue, but has here no 

 septa from its own structure. At the lower 

 third, it binds the tendons firmly down in their 

 places, and by its transverse fibres opposite the 

 ankle forms the anterior annular ligament of 

 that part.* From the anterior edge of the 

 fibula, this fascia passes over the two peronei 

 muscles, and is again inserted on the posterior 

 border of the bone, forming a sheath for these 

 muscles, and dividing them from the soleus. 

 The observations made above on the surgical 

 treatment of purulent collections refer especi- 

 ally to this anterior portion of the fascia of the 

 leg, on account of its greater strength, density, 

 and inelasticity. 



At the back part of the leg, the aponeurosis 

 is a continuation of that of the ham. We may 

 consider it as formed of two principal layers; 

 one superficial, and the other deep. Attached 

 to the posterior border of the fibula externally, 

 and to the inner margin of the tibia internally, 

 the first appears to arise from the expansion of 

 the tendons of the sartorius, gracilis, and semi- 

 tendinosus. Applied over the posterior surface 

 of the calf, it is lost below in the fibre-cellular 

 tissue surrounding the heel. This portion being 

 thin and yielding, it allows deep-seated ab- 

 scesses to become superficial with great facility. 

 The second layer is a continuation of the apo- 

 neurosis of the popliteal cavity, and descends 

 between the two layers of muscles ; but split- 

 ting into two, at the point where the soleus de- 

 taches itself from the deep parts, one of its 

 divisions follows the anterior surface of the 



* See ANKLE-JOINT, REGIONS OF. 



