Split-Thickness Skin Graft Augmentation with Amniotic Membrane

Split-thickness skin grafting (STSG) remains a workhorse for wound closure, but every graft creates two wounds: the recipient bed and the donor site. Amniotic membrane products are increasingly used as a wound covering and biological scaffold to support both STSG donor-site healing and recipient-site preparation. This review examines the clinical evidence for amniotic membrane augmentation in STSG care, with a focus on practical application for wound care physicians, podiatrists, orthopedic surgeons, and wound center coordinators.

Where amniotic membrane fits in STSG care

Amniotic membrane provides a biological matrix that supports cell adhesion and proliferation while modulating local inflammation. In periocular reconstruction, cryopreserved umbilical cord amniotic membrane has been used successfully as a skin substitute for anterior lamellar defects, with all reported wounds healing across nine sites in four patients followed for 10 to 22 months. The material was described as readily available, with antibacterial and anti-inflammatory properties, and as providing a structural scaffold for cell adhesion and growth. For STSG specifically, amniotic membrane has been studied as a donor-site dressing and as an adjunct to prepare complex recipient beds before grafting. These dual roles make it a useful option when standard dressings or immediate grafting alone may not be optimal.

Clinical evidence

Two systematic reviews and meta-analyses support the use of amniotic membrane for STSG donor sites. Liang et al. analyzed seven studies with 219 patients and found that amniotic membrane reduced mean healing time by 3.87 days compared with other treatments (95% CI, -4.39 to -3.35; P < 0.00001). There was no statistically significant difference in pain sensation (P > 0.05) or infection rate (relative risk 0.66; 95% CI, 0.29 to 2.18; P = 0.65).

Abul et al. pooled four studies enrolling 157 patients and reported a significant difference in wound healing time (P < 0.0001) and in the proportion of wounds healed by day 12 (P = 0.01), with no significant difference in infection rates (P = 0.27).

A prospective randomized trial by Hunger et al. compared amniotic membrane with split-thickness skin graft for radial forearm free flap donor-site coverage. Among 47 patients followed for 6 months, the amniotic membrane group healed more slowly (64.5 ± 38.4 days vs. 29.2 ± 8.9 days for STSG; P < 0.001). However, there were no differences in the prevalence of healing defects, dehiscence, or wound infection, and among 42 patients followed for 12 months, clinical, aesthetic, and functional outcomes were comparable. The authors concluded that amniotic membrane offers an alternative that avoids secondary donor-site morbidity.

In difficult wounds, amniotic membrane may serve as a bridge to STSG. Maier et al. treated four patients with pyoderma gangrenosum using dehydrated human amniotic/chorionic membrane following excisional debridement. All wounds produced granulation tissue and were subsequently closed with split-thickness skin grafts. Transcriptome analysis showed changes in local expression of inflammatory response, positive regulators of cellular proliferation, and extracellular matrix disassembly cytokines.

Loeffelbein et al. evaluated human amniotic membrane as a donor-site dressing in 45 patients randomized to HAM with polyurethane foam, polyurethane foam alone, or polyurethane foil/paraffin gauze. No difference in re-epithelialization or infection rate was found, but the amniotic membrane group had less ichor exudation and less pruritus.

Protocol considerations

Application technique varies by product form and wound location. For donor sites, amniotic membrane is typically applied after hemostasis and covered with a non-adherent secondary dressing. For recipient-site preparation, it may be placed after debridement to modulate inflammation and build granulation tissue prior to STSG. Because product handling, shelf life, and reimbursement vary by manufacturer and payer, clinicians should verify current coding and coverage policies with their wound center billing team and the product vendor. The evidence reviewed here does not establish a single standard protocol; treatment should be individualized to the patient and wound.

Comparison: amniotic membrane, STSG, and conventional dressings

The choice depends on whether the goal is donor-site coverage or recipient-site preparation. For STSG donor sites, meta-analytic evidence suggests amniotic membrane shortens healing time compared with conventional dressings without increasing infection risk. For radial forearm defects, STSG closed faster than amniotic membrane, but the 12-month functional and aesthetic outcomes were similar, and amniotic membrane spared a secondary donor site. For complex wounds such as pyoderma gangrenosum, amniotic membrane can create a graftable bed when STSG alone would be premature.

Application	Amniotic membrane	Alternative
STSG donor site	Faster mean healing time in meta-analyses; no significant infection increase	Conventional dressings: standard care, comparable infection rates
Radial forearm free flap donor site	Slower initial closure than STSG but comparable 12-month outcomes; avoids secondary donor site	STSG: faster closure but creates a second wound
Complex recipient bed	May generate granulation tissue and enable delayed STSG closure	Direct STSG or advanced dressing alone

Key takeaways

• Amniotic membrane has demonstrated faster healing time for STSG donor sites in meta-analyses, with no significant increase in infection risk.
• In a prospective randomized trial, amniotic membrane healed radial forearm donor sites more slowly than STSG but produced comparable 12-month outcomes without creating a secondary donor site.
• Amniotic membrane can prepare complex recipient beds, including pyoderma gangrenosum, for subsequent STSG closure.
• Reduced ichor exudation and pruritus have been reported compared with conventional dressings.