Text-book of forensic medicine and toxicology

by R. J. M. Buchanan

Examination of the Living.—With regard to the identification of the living, the presence of a medical man is seldom required, but there are many occasions when his opinion may be sought. Thus, under the Factory Acts, he may have to examine children about whose age doubts may have arisen. The Table on [p. 33], giving the periods at which the teeth appear, will assist him. A medical man may also be requested to give an opinion as to the mental soundness or unsoundness of an individual. He may also be consulted in cases where questions have arisen as to the existence and character of certain marks on the body—of deformities, either congenital or produced subsequent to birth, or of doubtful sex. The marks which most frequently give rise to differences of opinion are nævi materni, scars, and tattoo marks. In cases of doubtful sex, the male organs may resemble the female, the female the male, or they may be blended together in about equal proportions.

In all cases where an examination of a living person is required, the consent of the person must be obtained, the nature of the examination explained, and that any facts recorded will be used as evidence if required. If the person refuse to be examined then it must not be carried out.

Cicatrices.—The following questions may be put to the medical expert—(1) Do scars ever disappear? (2) Can the age of a scar be definitely stated?

In reply to the first and second questions, I shall quote the words of the late Professor Casper: “Consequently the scars occasioned by actual loss of substance, or by a wound healed by granulation, never disappear, and are always to be seen upon the body; but the scars of leech bites, or lancet wounds, or of cupping instruments, may disappear after a lapse of time that cannot be more distinctly specified, and may therefore cease to be visible upon the body. It is extremely difficult, or impossible, to give any certain or positive opinion as to the age of a scar.”

All cicatrices should be examined with oblique light and the aid of a lens. In the early stages a cicatrix is of a red colour, changes to brown, and later to white, and the surface glistens. In the intermediate stages one could not give any positive evidence of the age of a cicatrix. The probability is that a red cicatrix is a recent one, a white cicatrix is not recent.

I have seen well-defined cicatrices upon the back of a Russian, after incisions made by the blades of a cupping instrument fourteen years previously, and in an Englishman after twenty-five years (R. J. M. Buchanan).

Devergie states that where the brand of a galley-slave has vanished, it may be recalled by slapping its usual position with the palm of the hand. The scar remains white, while the skin round it is reddened. A change of temperature to the part will sometimes cause the reappearance of a vanished scar. Washing may also help to reproduce scars. Cicatrices produced in childhood may grow with the ordinary growth of the individual. The shape of a cicatrix will depend upon the character of the wound which produced it; on the nature of the healing process; on the elasticity or tension of the skin; on the convexity of the part; and on the looseness of the subcutaneous cellular tissue. An incised wound healing by the “first intention” will most probably leave a white linear cicatrix; on the other hand, a wound healing by granulation will leave a more or less irregular scar. The position of a wound on the body also modifies the subsequent cicatrix; thus a linear cicatrix is produced when the wound is in the long diameter of the limb, a more or less oval one when across the limb. The retraction of the skin in the latter case tends to draw the skin at right angles to the line of incision, thus approximating the extremities of the cut, increasing it in breadth and lessening it in length. Owing to one or more of the above-mentioned conditions the typical cicatrix of an incised wound is elliptical, tending, however, in some cases to assume a circular form. Linear cicatrices are found chiefly between the fingers and toes, and where the cutaneous surfaces are concave. In gunshot wounds the resulting cicatrix is depressed and disc-shaped, and more or less adherent in the centre to the subcutaneous tissues, and if the weapon be fired close to the surface of the body, grains of unburnt powder may be seen in the surrounding skin. Cicatrices from burns are, as a rule, large, irregular, and superficial, and frequently give rise to deformity. A scar left by caustics is circumscribed, deep and depressed in the centre. Cicatrices in the groins are probably venereal; those in the neck and under the jaw, strumous. Scars from operation incisions are much less evident now than when wounds were more likely to suppurate and heal by granulation. It is remarkable, after an incision made with aseptic precautions and healing by first intent, as time progresses the cicatrix becomes less and less noticeable, but they can be detected by methods described above. Fine punctures and stitch cicatrices may eventually leave little or no trace.

Dupuytren and Delpech state that the tissue formed in a cicatrix is never converted into true skin—the rete mucosum when once destroyed never being re-formed. It contains no sebaceous glands, sweat glands, or hair follicles, and is but slightly vascular. This may account for the white colour of ordinary cicatrices, but even to this rule exceptions may be taken, and dark brown patches of pigment have been known to mark the situation of old lacerated wounds. It must be remembered also that in irregular wounds and in incised wounds which may heal with an uneven joint, that portions of skin may become embedded or grow into the scar tissue and give rise to difficulty in forming an opinion. I have seen a well-defined dark coloration of the skin continue for three months after the application of a mustard plaster, followed at the time by desquamation.

Tattoo Marks.—With regard to tattoo marks, the question of their disappearance gave rise to considerable discussion in the celebrated Tichborne case. On this subject the experiments of Hutin, Tardieu, and Casper appear to point to the fact “that tattoo marks may become perfectly effaced during life,” but that after death the colouring matter with which the marks were made may be found in the lymphatic glands. This is especially the case when vermilion is used. The most permanent marks are made with Indian ink, powdered charcoal, gunpowder, washing blue or ink, and vermilion. These are given in the order of their permanency. Hutin found that in 506 men who had been formerly tattooed, the marks had disappeared from 47 of the number. Not only does permanency depend upon the colouring matter used, but also upon the depth to which it has penetrated. If superficial, it may gradually become effaced. If the material be carried down to the papillæ, it will remain permanent, and can only be removed in such a way as to leave a scar. But besides the spontaneous disappearance of tattoo marks from the lapse of time, these marks may be artificially removed, and in such a manner as to prevent the possibility of a definite opinion being given as to their primary character. The presence of a scar in the situation of a well-known tattoo mark is suspicious. Thus, the Claimant had a scar on a part where it was sworn that Arthur Orton had been tattooed. The application of strong acetic acid, potash, hydrochloric acid and glycerole of papain appears to be the means adopted for the removal of tattoo marks. Efforts are made to remove superficial tattoo marks by removing the particles with needles. Tattoo marks according to their position and design are useful evidence of identification.

Birth Marks.—The presence and characters of birth marks should be noted for purposes of identification. Their removal may be possible, but, except in such as are small and superficial, the process used for removal leaves traces behind in the form of cicatrices or irregularities of surface, which may generally be detected in oblique light and with the aid of a good lens. Large moles or nævi may he excised, but a cicatrix will remain, which will differ in shape from the original mark.