Exploring the potential of dermal grafting: a narrative review in plastic surgery

INTRODUCTION

Skin grafting is an essential and extensively utilized reconstructive method for addressing skin defects, regardless of their cause or anatomical location. Among the various free grafts used in reconstructive surgery, such as split-thickness skin grafts (STSGs), full-thickness skin grafts (FTSGs), and composite grafts, STSGs are the most frequently employed and have the broadest application in routine surgical practice^[1,2].

An STSG is defined as a free tissue transfer deliberately separated from a donor site and transplanted to a recipient site, where the graft relies on capillary ingrowth for survival. While the concept of skin grafting is ancient, the modern STSG technique was first described in the 1872-ties by Ollier^[3] and Reverdin^[4]. Remarkably, this procedure has remained largely unchanged for 150 years^[2,3,4].

Despite its widespread use, the STSG technique has notable limitations, including donor site morbidity and recipient site scarring^[5]. This is especially problematic in burn management, where scar contracture and the characteristic mesh or MEEK patterns post-transplantation contribute to suboptimal healing and scarring^[2].

Meshing or the MEEK procedure is typically performed to extend the graft over a larger area, as STSGs are inelastic. However, for facial regions, STSGs are left unmeshed to avoid the unattractive mesh pattern and reduce scarring. An unmeshed STSG, or sheet graft, improves scar quality but requires a larger donor site^[2].

An alternative technique involves using only the dermis portion as a graft. This approach harvests skin in two layers from the same site: a traditional STSG of the upper layer and a dermal graft (DG) of the lower layer. The upper part is returned to the donor site, while the dermal portion is grafted to the recipient site^[2]. This method has gained attention for its potential to reduce issues at both donor and recipient sites, with the DG’s elasticity potentially reducing the need for meshing or the use of the MEEK technique at the recipient site^[2,6-9]. Furthermore, it needs to be emphasized that the dermal graft re-epithelializes from the epidermal appendages included in the dermal graft and no STSG is needed for wound closure.

HISTORICAL ASPECTS OF DERMAL GRAFTING

The initial idea of using a separate dermal component in STSG procedures was introduced by Hynes in 1954 as an alternative to conventional flap techniques^[2,10]. Following this, two publications described a modified technique where the DG was inverted at the recipient site, allowing it to vascularize before a secondary STSG was applied after two weeks^[2,7].

Tanabe et al. used dermal grafting to reconstruct palmar skin defects, achieving a 99.1% graft take rate with excellent aesthetic results and no scarring^[9]. In this method, the STSG was harvested first, followed by the dermis graft, which healed at the recipient site without scarring within 7-8 days^[2].

Querings et al.^[11] reported favorable functional and aesthetic outcomes with dermal grafting^[2]. An experimental study by Rubis et al.^[8] using a porcine model showed slower epithelialization at the dermal recipient site but achieved complete healing within two weeks^[2].

Kogan et al.^[12] studied eight patients and found good dermal graft take rates at the recipient site^[2]. Han et al.^[6] conducted the largest study, comparing dermal grafting to STSG, and found less severe scarring at the recipient site with the dermal graft technique^[2].

Kang et al.^[13] demonstrated successful dermal graft application over exposed bone and tendons in a small case series^[2]. These findings align with the results of a study conducted by Lindford et al.^[14]. In this study, 16 dermal grafts performed on nine patients were compared to regular STSG. The time to epithelialization of the dermal grafts at the recipient sites ranged from 12 to 35 days (median 21 days), with all grafts achieving > 90% epithelialization by 4 weeks. There was no significant difference in donor site healing times between the DG “deeper” donor site (range 7-35 days, mean 16.1 days) and the conventional STSG donor site (range 7-35 days, mean 16.7 days). The donor sites were located on the backs of the patients^[2].

Han et al. conducted a retrospective study showing satisfactory aesthetic and functional outcomes when using dermal grafts to cover small skin defects on the face after tumor resection^[15]. Most patients had high-quality skin characteristics and excellent satisfaction with the dermal grafts for both functional and aesthetic results at the recipient sites^[2]. A recent dual-center, international study [“Trial registration: ClinicalTrials.gov Identifier (NCT05189743) 12/01/2022”] by Dogan et al.^[2] highlighted reduced donor site morbidity and favorable long-term recipient site outcomes with dermal grafting, owing to its elasticity and reduced need for meshing^[2].

TECHNICAL ASPECTS

The dermal grafting technique represents a novel approach, and there is currently no established instrument specifically designed for DG harvesting. In short, regular DG harvesting involves first taking a regular STSG followed by harvesting a second graft from the same skin area with high precision, ensuring it is of the same size; the second skin strip is the DG. Consequently, significant training is required to achieve satisfactory graft yields using a conventional dermatome, which resulted in the limited sample sizes in the present studies^[2]. We also believe this may explain why the technique has not been further explored in previous attempts, and why most of the evidence presented in this review regarding the DG technique is based on small patient series. The process of obtaining a DG is significantly more technically demanding compared to the conventional STSG harvest. While the first layer, the STSG, is typically managed with relative ease by a trained plastic surgeon, the harvesting of the second layer, the DG, poses significant challenges. These challenges can be summarized as follows^[2]:

1. Lack of tissue firmness: The dermal tissue exhibits less firmness compared to the epidermis, making it difficult to ascertain the precise thickness of the graft during harvesting when addressing the skin the second time with the dermatome.

2. Precise border alignment: To obtain a proper DG, the second harvesting procedure needs to be meticulously adjusted to align with the first, as the four borders of the previously harvested STSG need to be in precise alignment to avoid obtaining a deranged dermal graft, as the dermatome is tilted between uncut skin and the wound of the previous graft.

These challenges have hindered the implementation of the technique despite its evident advantages.

ADVANTAGES OF DERMAL GRAFTING IN PLASTIC AND RECONSTRUCTIVE SURGERY

PRELIMINARY RESULTS WITH A NEW MULTIBLADE DERMATOME AND FUTURE WORK

Recent advancements in dermal grafting technology have led to the development of a multiblade dermatome, designed to address the technical challenges associated with harvesting dermal grafts using traditional single-blade dermatomes. The study presented below describes the development and initial application of a novel multiblade dermatome, designed to concurrently harvest a conventional STSG and a DG within a single surgical procedure. Traditional methods of DG extraction have faced significant technical challenges, limiting their clinical adoption. However, this new prototype aims to overcome these obstacles, potentially broadening the usage of dermal grafting techniques.

Initial experiments with this device [Figure 1] (Patent, Reg. 2050787-7 and 21739981.5) on four human cadavers demonstrated its capability to produce at least two distinct grafts with predetermined thicknesses, simplifying what has typically been a complex and demanding surgical task. The thickness of the dermal graft can be adjusted within the desired range by modifying the opening at the second cutting blade. As shown in the paper, this adjustment enables the production of dermal grafts with thicknesses ranging from 200 to 1,000 µm. At the microscopic level, the uniformity of both the upper and lower grafts confirmed the precision of the dermatome, and the ease of use was documented in parallel and thus supported its future potential. This proof-of-concept study highlights the multiblade dermatome’s feasibility in producing dual grafts, suggesting a future where dermal grafting could be more accessible and practical in clinical settings^[15].

Figure 1. The first prototype of a multi, e.g., double-blade dermatome. The two blades and the opening for tissue transfer are marked in green.

Preliminary results utilizing this new device are promising. The multiblade dermatome allows for more precise and consistent cuts, significantly reducing the technical difficulty of the procedure. This innovation not only simplifies the harvesting process but also enhances the quality of the dermal grafts obtained, leading to better integration and healing at the recipient site.

FUTURE WORK

One challenge that needs further exploration is the expansion level of the DG and its relationship with the healing process. Another topic of interest is the choice of thickness for the DG component, where two issues evolve. Firstly, there is a need for a thicker dermal component in the reconstruction of areas with restrictive scars or contractures. Secondly, the multiblade dermatome can be adjusted to take different thicknesses of the graft, and the choice of thickness needs to be explored, also from the point of creating a full-thickness skin defect. The variability of the dermal component thickness needs to be included in the decision process, as different body areas, such as the back, limb, and sole, provide dermal areas with varying thicknesses. Additionally, the value of generating more than two strips with a multiblade dermatome needs to be further explored.

Future work will also focus on further refining the multiblade dermatome to optimize its performance and ease of use. Additionally, clinical trials are needed to validate the long-term benefits of using this device in various reconstructive procedures. Researchers are also exploring the potential for combining the multiblade dermatome with other advanced technologies, such as tissue engineering, to further enhance the precision and efficiency of dermal grafting. These efforts aim to make dermal grafting more accessible and practical for a wider range of clinical applications, ultimately improving patient outcomes in plastic and reconstructive surgery.

SUMMARY

The review traces the historical development of skin grafting, leading to the introduction of dermal grafting in the early 21st century as a novel approach to overcome the limitations of conventional techniques. Four main advantages of dermal grafting are highlighted:

Accelerated healing at donor sites compared to conventional split-thickness grafts.

Improved aesthetic outcomes due to the elastic nature of dermal grafts, enabling application without meshing for a smoother appearance.

Increased graft availability by effectively at least doubling the material from a single donor site, when using a double-blade dermatome as compared to a singleblade one.

Utility in the reconstruction of areas with restrictive scars or contractures.

Recent innovations like the multiblade dermatome have addressed technical challenges in harvesting dermal grafts, potentially broadening clinical adoption. Initial studies demonstrate the feasibility of this device in concurrently producing split-thickness and dermal grafts, significantly simplifying the surgical procedure.

Key areas of future work include optimizing the multiblade dermatome, exploring expansion levels and thickness variability of dermal grafts, conducting large clinical trials to validate long-term benefits, and combining dermal grafting with advanced technologies for tissue regeneration.

Overall, this review highlights dermal grafting’s significant advantages and potential to revolutionize plastic and reconstructive surgery, ultimately improving patient outcomes and quality of life.