CICATRIX. 



605 



which the ulcer was subjected in the process of 

 healing. When these have been considerable, 

 the hardness is correspondingly great, while, if 

 the cure has been expeditious and the part 

 been kept extended and irritation avoided, the 

 cicatrix remains soft, thin, and pliable, a point 

 of great importance in practice as applied to 

 the healing of burns. 3. The colour of the 

 new skin is different from the natural parts. 

 This arises from the want of rete mucosum, 

 which is not regenerated till long after the 

 other tissues, and sometimes not at all. For 

 this reason a cicatrix in a Black is as white as 

 that in an European ; but after a considerable 

 lapse of time, this structure is sometimes 

 formed anew, and in some instances becomes 

 even of a darker colour than before. 4. The 

 surface is perfectly dry from the want of ex- 

 halent pores, which are never found to be 

 restored even in the oldest cicatrices. Indeed, 

 in cases where the chorion has not been de- 

 stroyed through its entire thickness, the loss 

 of substance reaching only through its outer 

 layers, these pores are generally obliterated, 

 and the important exhalent function of the 

 skin is annihilated; and even when the injury 

 has extended only through the external vas- 

 cular structure of the skin, as is the case in the 

 healing of a blister which has been long in- 

 flamed, we have observed a drier state of the 

 parts, and more polished than the surrounding 

 skin which had not been injured. From this pe- 

 culiarity in the cicatrix, when the whole body is 

 bathed in sweat these parts are dry and po- 

 lished. This state of dryness, however, partly 

 results from another anatomical deficiency, 

 namely, of the perspiratory glands, which are 

 destroyed in cases where the entire integument 

 has been injured, and these are of course never 

 regenerated. 5. The new tissue contains no 

 hairs, and if, after superficial wounds, a few 

 scattered hairs appear on the surface, they are 

 feeble and white. 6. After the healing of a 

 large ulcer of long standing, the new surface 

 is sometimes much lower than the surround- 

 ing skin. Nature seems, in these cases, to 

 have exhausted her energies in the long en- 

 deavour to heal the ulcer, and the granulations 

 never rise to the level of the surrounding skin, 

 as in recent cases. The new cuticle there- 

 fore commences upon those granulations which 

 shoot from the elevated edges of the ulcer, and 

 the cicatrizing process is thus led as it were 

 into the hollow of the ulcer, and spreads along 

 its surface, completing the cicatrix in an exca- 

 vated form. 7. The elasticity of the cellular 

 tissue under the new chorion is less than that 

 of the ordinary cellular web; nor does it allow 

 of distension to the same degree. This is 

 seen in cedema and emphysema, where this 

 part will often remain depressed while the sur- 

 rounding parts are raised and distended ; it is 

 also seen in the impediments which large cica- 

 trices prove to the movements of the joints. 

 The same circumstance perhaps also gives a 

 reason for there being no fat contained in these 

 parts. This want of extensibility seems to be 

 but one consequence of the law which regu- 

 lates the products of inflammatory action. The 

 elastic power is materially diminished in the 



natural cellular tissue by inflammation, a de- 

 gree of stiffness and difficulty of movement 

 remaining for a long time after ; and as the 

 tissue of a cicatrix is, ab initio. the product of 

 inflammatory action, it is to be expected that it 

 should shew the same effects. 



How far are the vascular and nervous func- 

 tions of the lost part restored in the cicatrix ? 

 It is probable that the new structure receives 

 nerves, but in small number. Of those senses 

 which can be implicated in the destructive 

 process of ulceration, that of touch alone seems 

 to be restored. This is so in a marked though 

 still imperfect degree, the sensation in these 

 parts being somewhat of that dull kind expe- 

 rienced after paralysis. 



On the temperature of the cicatrix we have 

 not made sufficient observations to generalize, 

 but we have found that the actual temperature 

 of the bridle from a burn, while it retains its 

 hardness, is several degrees above that of the 

 healthy skin, while the power of retaining its 

 temperature, or of resisting the extremes of 

 heat and cold, is much inferior in the cicatrix to 

 that which the healthy skin possesses, although 

 the actual temperature, under ordinary circum- 

 stances, is the same as the surrounding skin. 

 Almost every traveller to the Poles or to the 

 Tropics mentions the liability of old ulcers that 

 had been healed, to announce the extremes of 

 temperature by pain and inflammation. 



The bloodvessels of the new structure are at 

 first numerous, as indicated by the redness and 

 the readiness with which it bleeds, but after- 

 wards they diminish much in size and number, 

 so that, in an old cicatrix, it is often impos- 

 sible to force an injection into them. M. Du- 

 puytren tells us that in scars upon the face the 

 greatest heat from exercise, or the influence of 

 the mind in producing blushing, leaves this 

 part uncoloured amid the surrounding redness.* 

 Bichat assures us that even the new epidermis 

 itself is overrun with bloodvessels.f We have 

 certainly never been able to discover the least 

 trace of vascularity in it, nor have we found 

 that sensibility in this part which he describes. 

 It seems to be a matter of doubt at present how 

 far the function of secretion exists in the new 

 production. Dr. Bright seems to believe in its 

 restoration, since he says that the scar in one of 

 his observations appeared to be covered with a 

 true mucous membrane ; but it is right to stale 

 that the proof he gives of this is rather equi- 

 vocal, namely, that the surface was quite con- 

 tinuous with the membrane lining the rest of 

 the canal; " indeed," he adds, " when inspect- 

 ing the ulcer in the process of healing, we per- 

 ceive the vessels of the mucous membrane 

 running over the surface to be repaired. "J M. 

 Troillet mentions in round terms that the cica- 

 trix had the thickness, consistence, and ap- 

 pearance of mucous membrane ; but neither 

 he nor Dr. Bright says any thing in particular 

 as to the villous structure, which we conceive to 

 be an essential characteristic of some forms of 



* Le9ons de Clinique Chir. torn. ii. p. 47. 

 t General Anatomy, Transl. vol. ii. p. 899. 

 j Med. Reports, vol. i. p. 182. 

 $ Med. Chir. Rev. vol. v. p. 194. 



