However, as an invasive technique, surgery has a high risk of inducing the new scar formation and recurrence of scarring. It is taken to correct the deficiencies and deformities and is especially applicable when a patient has functional impairment caused by contracture of the scar. Surgical intervention is currently one of the mainstream methods for the treatment of traumatic scars. Many treatment options have been developed for the management of traumatic scars, which are divided into surgical and non-surgical approaches. The early stage scars have diffuse capillaries and excessive abnormally arranged collagen fibers in histology, which manifest as red hypertrophic scars, whereas the late stage of scars has closed vessels and excessive fiber deposition, which manifest as normal color or reduced color scars with elevation, flat, or atrophy in morphology. The dysregulation of proliferation and apoptosis of fibroblasts, an imbalance between synthesis and degradation collagen in the extracellular matrix, and abnormal structure of epithelium are responsible for scarring. Traumatic scars, therefore, are the results of wound healing after tissue injury. Even after remodeling for many years, the wounded tissue never regains the properties of uninjured skin. During the remodeling phase, a variety of extracellular matrix (collagen and elastic fiber) and their corresponding enzyme system (matrix metalloproteinases) act to achieve the purpose of restoring normal histological structure. The remodeling phase can take up to a year or longer to complete, which is characterized by the rearrangement of granulation tissue, the replacement of collagen III by collagen I, and the contracture of the lesion through the action of myofibroblasts. Keratinocytes from the edge of the wound and adnexal structures migrate and proliferate to make the wound healed by re-epithelialization. Angiogenesis is initiated by the function of endothelial cells in response to the upregulation of vascular endothelial growth factor (VEGF). Activated by the cytokines and growth factors, such as transforming growth factor beta (TGF-β) and platelet-derived growth factor (PDGF) released mainly from macrophages, fibroblasts are induced to produce collagen and extracellular matrix. The proliferation phase was accomplished by the migration and proliferation of various cells. Excessive inflammation response, resulting from infection for instance, often leads to abnormal wound healing and increases the risk of scarring. A moderate amount of inflammation is vital to the wound healing process for transition from the inflammatory phase to the proliferative phase.

The inflammation is crucial to the removal of dead tissue and the prevention of infection by neutrophils and macrophages through the actions of phagocytosis and the secretion of proteases and cytokines. Īlthough the complete pathogenesis of traumatic scars needs further elucidated, the formation of pathological scars is regarded as a result of dysregulation in the process of wound healing which characterizes by an inflammatory phase, a proliferative phase, and a remodeling phase. It should always be noticed that patients with traumatic scars are prone to having anxiety, depression, or even the serious consequence of suicide. Severe linear or diffuse contracted scars usually require aggressive therapy such as surgical intervention to relieve tension and ultimately improve range of motion and correct the deformities. Restricted range of motion of the functional joints and the deformities of facial organs resulted from contracture are among the most severe morbidities. Up to 87% of burn patients especially those with hypertrophic scars report the symptom of pruritus, which disrupts sleep and daily activities. Pruritus and pain associated with traumatic scars are major and very common morbidities. Besides the cosmetic effects, there are several other morbidities associated with traumatic scars. The traumatic scars especially those on the face and neck are cosmetically unappealing due to dyschromia and irregular texture compared to the surrounding skin. The prevalence of hypertrophic scar, the most common type of traumatic scars, is reported as high as 70% after burn injury.

Scarring is regarded as one of the inevitable consequences of trauma. Tens of millions of individuals acquire traumatic scars every year caused by burns and other traumatic injuries worldwide.

Road burn scars