Split-Thickness Skin Grafts (SSGs): Overview
A split-thickness skin graft is a surgical technique that harvests the epidermis and a portion of the dermis to cover wounds, serving as the gold standard for major traumatic skin loss and deep burns. 1
Basic Technique and Characteristics
SSGs involve harvesting partial-thickness skin (epidermis plus partial dermis) from a donor site to cover recipient wounds, particularly in burn and reconstructive operations 2
The grafts can be meshed at various ratios (1.5:1,3:1, or 4:1) to expand coverage area and reduce donor site morbidity, or applied non-meshed for smaller wounds 2, 3
Meshing allows for drainage of fluid beneath the graft and enables greater expansion of limited donor skin, which is critical in large burns where donor skin availability is limited 1
Donor Site Management
The donor site creates a secondary wound that heals by re-epithelialization from dermal appendages, typically requiring 9-14 days 4
Transparent film dressings are the optimal choice for donor site care, associated with healing in 9.47 days, minimal pain (1.59 on 0-10 scale), low infection rate (3%), and minimal cost 4
In high-risk patients with poor wound healing potential (elderly, diabetic, malnourished), "back grafting" the donor site with an additional meshed graft (4:1) can convert the open wound to a covered wound, potentially decreasing healing time and complications 2
Clinical Application by Wound Size
For large lower extremity wounds (>150 cm²), 3:1 meshing demonstrates the lowest complication rates and acceptable healing outcomes, making it the preferred ratio for extensive coverage 3
For smaller wounds (<40 cm²), non-meshed grafts are appropriate despite higher rates of graft loss (19.1%) and ulcer recurrence (18.3%) compared to meshed alternatives 3
All meshing ratios achieve similar long-term healing by final follow-up (approximately 16 months), though meshed grafts show faster initial healing at 30 and 60 days 3
Important Caveats
Regrafting donor sites in healthy young patients may worsen long-term cosmetic outcomes despite initial improvement, so this technique should be reserved for patients with genuine healing concerns rather than applied routinely 5
Donor site morbidity includes pain, scarring, and risk of delayed healing, particularly problematic in patients with comorbidities affecting wound healing 2, 1
Emerging technologies (Xpansion Micrografting, fractional harvesting, ReCell) offer higher expansion ratios and decreased donor morbidity but require further clinical validation before routine use 1