Autologous Graft Thickness Affects Scar Contraction and Quality in a Porcine Excisional Wound Model.

BACKGROUND: Texture, color, and durability are important characteristics to consider for skin replacement in conspicuous and/or mobile regions of the body such as the face, neck, and hands. Although autograft thickness is a known determinant of skin quality, few studies have correlated the subjective and objective characters of skin graft healing with their associated morphologic and cellular profiles. Defining these relationships may help guide development and evaluation of future skin replacement strategies. METHODS: Six-centimeter-diameter full-thickness wounds were created on the back of female Yorkshire pigs and covered by autografts of variable thicknesses. Skin quality was assessed on day 120 using an observer scar assessment score and objective determinations for scar contraction, erythema, pigmentation, and surface irregularities. Histological, histochemical, and immunohistochemical assessments were performed. RESULTS: Thick grafts demonstrated lower observer scar assessment score (better quality) and decreased erythema, pigmentation, and surface irregularities. Histologically, thin grafts resulted in scar-like collagen proliferation while thick grafts preserves the dermal architecture. Increased vascularity and prolonged and increased cellular infiltration were observed among thin grafts. In addition, thin grafts contained predominately dense collagen fibers, whereas thick grafts had loosely arranged collagen. α-Smooth muscle actin staining for myofibroblasts was observed earlier and persisted longer among thinner grafts. CONCLUSIONS: Graft thickness is an important determinant of skin quality. High-quality skin replacements are associated with preserved collagen architecture, decreased neovascularization, and decreased inflammatory cellular infiltration. This model, using autologous skin as a metric of quality, may give a more informative analysis of emerging skin replacement strategies.

Recipient wound bed characteristics affect scarring and skin graft contraction.

The use of autograft skin is essential in the treatment of full thickness burns and large cutaneous defects. Both autograft thickness and condition of the wound bed modulate aesthetic and functional outcomes. Thicker autografts contract less and maintain greater functionality as the scar matures. The presence of hypodermis can also positively affect the eventual appearance and functionality of the wound site by modulating contraction and alleviating inflammation and cellular stress responses. In this study, we characterize wound-site physical and cellular characteristics following split-thickness skin grafting onto hypodermis vs. onto fascia. Compared to autografts grafted onto fascia, identical thickness autografts grafted onto fat demonstrated reduced contraction, enhanced mobility and vascularity, and reduced topographical variability. Grafts onto fat also showed reduced levels of myofibroblasts and leukocytic infiltration. The status of the wound bed prior to engraftment is an important contributor of skin quality outcome. The presence of hypodermis is associated with improved functional and aesthetic qualities of split thickness skin grafts, which are correlated with reduced presence of myofibroblasts and leukocytic infiltration.

Characterization and management of mandibular fractures: lessons learned from Iraq and Afghanistan.

Fractures of the mandible are among the most common facial injuries. Invasiveness of treatment should be determined by the extent of injury: degree of displacement, number of fractures, the patient's health status, and concomitant injuries. Complex, comminuted, and avulsive injuries frequently seen in combat will require coordination with multiple specialties to provide the best treatment. Stabilization treatment with arch bars or external fixators and splints is often desirable when fractures are highly comminuted or the soft tissue envelope is compromised by tissue loss or burns. In severe injuries, many times reconstruction will take several surgeries. Debridement of necrotic tissue and devascularized bone and skin grafting often are necessary before reconstruction. Microvascular or myocutaneous flaps should be considered with significant tissue loss and osteocutaneous flaps when large continuity defects are present. Most mandible fractures are repaired in a single operation. Those caused by explosives and high-velocity projectiles are more complex. Research should continue to focus on improving outcomes for these patients. Advances in tissue engineering, bone regeneration, and composite tissue allografting will have to continue if we hope to restore facial form and function for our combat wounded.

Head and neck manifestations of tuberculosis.

TB is a serious communicable disease that causes 2 million deaths a year worldwide. It is estimated one third of the world's population is infected with TB. TB has proved difficult to eradicate. Laboratory testing also has been challenging, with as many as 19% of TB cases failing to show positive bacteriology tests. Head and neck masses and oral lesions always should be included in the differential diagnosis of TB, especially in high-risk patient populations. A combination of clinical suspicion, extensive laboratory analysis, and radiographic examination is invaluable in treating and preventing the spread of this insidious but deadly disease that has plagued mankind for ages.