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.