Scars
The most superficial wounds such as superficial
burns and abrasions will heal by epithelialisation alone without scar formation.
In these circumstances adnexal structures are preserved and the epithelium
regenerates from these structures. This may leave alterations in
keratinisation, texture or pigmentation of the healed area, but not scarring as
such. A scar is the inevitable consequence of wound repair. The final phase of
wound repair is the process of remodelling and scar maturation (Fig.
3.1). The
fibroblasts, capillaries, glycosaminoglycans, and immature collagen of
granulation tissue and the newly healed wound are replaced by relatively
acellular, avascular scar tissue composed of mature collagen with scattered
fibroblasts. This biological process is manifested by a change in appearance
of the scar from a red, raised, firm, contracting, perhaps itchy nodule to a
pale, flat, softer, static, symptomless plaque of mature scar. The rate at which
any given scar passes through this process can vary widely depending on the age
of the individual, the site of the wound, the time the wound took to heal, the
direction of the scar and the tension across it (Fig.
3.13). In general, scars
in younger patients with wounds on the trunk that heal slowly, perhaps with
infection or dehiscence, and scars that have a lot of tension across them will
take much longer to mature than scars in older people, in thin-skinned areas,
that heal rapidly by first intention and that have minimal tension across them (Table
3.2). It is important to be aware of this variation in the natural
history of scar maturation in order to counsel patients regarding the likely
progress and outcome of their scar, advise those having elective surgery what
the consequences in terms of scarring will be, and to recognise the various
types of adverse scarring which can occur. One of the most frequent types of
adverse scar, a hypertrophic scar, is one that remains red, raised, itchy and
tender for longer than might generally be expected.