#Punctured Wounds.#—­Punctured wounds are produced by narrow, pointed instruments, and the sharper and smoother the instrument the more does the resulting injury resemble an incised wound; while from more rounded and rougher instruments the edges of the wound are more or less contused or lacerated.  The depth of punctured wounds greatly exceeds their width, and the damage to subcutaneous parts is usually greater than that to the skin.  When the instrument transfixes a part, the edges of the wound of entrance may be inverted, and those of the exit wound everted.  If the instrument is a rough one, these conditions may be reversed by its sudden withdrawal.

Punctured wounds neither gape nor bleed much.  Even when a large vessel is implicated, the bleeding usually takes place into the tissues rather than externally.

The risks incident to this class of wounds are:  (1) the extreme difficulty, especially when a dense fascia has been perforated, of rendering them aseptic, on account of the uncertainty as to their depth, and of the way in which the surface wound closes on the withdrawal of the instrument; (2) different forms of aneurysm may result from the puncture of a large vessel; (3) perforation of a joint, or of a serous cavity, such as the abdomen, thorax, or skull, materially adds to the danger.

Treatment.—­The first indication is to purify the whole extent of the wound, and to remove any foreign body or blood-clot that may be in it.  It is usually necessary to enlarge the wound, freely dividing injured fasciae, paring away bruised tissues, and purifying the whole wound-surface.  Any blood vessel that is punctured should be cut across and tied; and divided muscles, tendons, or nerves must be sutured.  After haemorrhage has been arrested, iodoform and bismuth paste is rubbed into the raw surface, and the wound closed.  If there is any reason to doubt the asepticity of the wound, it is better treated by the open method, and a Bier’s bandage should be applied.

#Contused and Lacerated Wounds.#—­These may be considered together, as they so occur in practice.  They are produced by crushing, biting, or tearing forms of violence—­such as result from machinery accidents, firearms, or the bites of animals.  In addition to the irregular wound of the integument, there is always more or less bruising of the parts beneath and around, and the subcutaneous lesions are much wider than appears on the surface.

Wounds of this variety usually gape considerably, especially when there is much laceration of the skin.  It is not uncommon to have considerable portions of skin, muscle, or tendon completely torn away.

Haemorrhage is seldom a prominent feature, as the crushing or tearing of the vessel wall leads to the obliteration of the lumen.