Utilization of laser Doppler flowmetry and tissue spectrophotometry for burn depth assessment using a miniature swine model

Currently, the diagnosis of burn depth is primarily based on a visual assessment and can be dependent on the surgeons' experience. The goal of this study was to determine the ability of laser Doppler flowmeter combined with a tissue spectrophotometer to discriminate burn depth in a miniature swine burn model. Burn injuries of varying depth, including superficial‐partial, deep‐partial, and full thickness, were created in seven Göttingen minipigs using an aluminium bar (100 °C), which was applied to the abdominal skin for periods of 1, 3, 6, 12, 30, and 60 seconds with gravity alone. The depth of injury was evaluated histologically using hematoxylin and eosin staining. All burns were assessed 3 hours after injury using a device that combines a laser light and a white light to determine blood flow, hemoglobin oxygenation, and relative amount of hemoglobin. The blood flow (41 vs. 124 arbitrary units [AU]) and relative amount of hemoglobin (32 vs. 52 AU) were significantly lower in full thickness compared with superficial‐partial thickness burns. However, no significant differences in hemoglobin oxygenation were observed between these depths of burns (61 vs. 60%). These results show the ability of laser Doppler flowmeter and tissue spectrophotometer in combination to discriminate between various depths of injury in the minipig model, suggesting that this device may offer a valuable tool for burn depth assessment influencing burn management.     

Cutaneous microcirculatory assessment of the burn wound is associated with depth of injury and predicts healing time

Rationale

Current trends for the treatment of deep partial thickness and full-thickness burns include early excision and skin grafting. In this study we retrospectively evaluated the ability of Laser Doppler Flowmetry (LDF), taken within 24 h of the burn to predict: (1) burn wound depth and (2) wounds which would heal in less than 21 days.

Method

The Laser Doppler Flowmeter (O2C, LEA Medizintechnik, Germany) was employed to non-invasively measure the cutaneous microcirculation of 173 selected areas on 28 patients who suffered burns.

Results

A distinct association between initial flow (<24 h after burn injury) and the clinical assessment of depth of burn wounds was observed. Wounds demonstrating an initial blood flow of >100 AU were, in 93.1% of cases, correctly (positively) predicted for spontaneous healing within 21 days. A blood flow of <100 AU (negatively) predicted in 88.2%, those wounds which would not go on to heal within 21 days. Sequential measurement analysis (<24 h, 3 days after injury and 6 days after injury) revealed no significant decrease in skin perfusion velocity or flow rate.

Conclusion

LDF can provide immediate results for early determination of burn wound depth and is useful in selecting patients for conservative treatment of their burn wounds.     

Predictors of re-epithelialization in pediatric burn

Introduction

An important treatment goal for burn wounds is to promote early wound closure. This study identifies factors associated with delayed re-epithelialization following pediatric burn.

Methods

Data were collected from August 2011 to August 2012, at a pediatric tertiary burn center. A total of 106 burn wounds were analyzed from 77 participants aged 4–12 years. Percentage of wound re-epithelialization at each dressing change was calculated using Visitrak™. Mixed effect regression analysis was performed to identify the demographic factors, wound and clinical characteristics associated with delayed re-epithelialization.

Results

Burn depth determined by laser Doppler imaging, ethnicity, pain scores, total body surface area (TBSA), mechanism of injury and days taken to present to the burn center were significant predictors of delayed re-epithelialization, accounting for 69% of variance. Flame burns delayed re-epithelialization by 39% compared to all other mechanisms (p = 0.003). When initial presentation to the burn center was on day 5, burns took an average of 42% longer to re-epithelialize, compared to those who presented on day 2 post burn (p < 0.000). Re-epithelialization was delayed by 14% when pain scores were reported as 10 (on the FPS-R), compared to 4 on the first dressing change (p = 0.015) for children who did not receive specialized preparation/distraction intervention. A larger TBSA was also a predictor of delayed re-epithelialization (p = 0.030). Darker skin complexion re-epithelialized 25% faster than lighter skin complexion (p = 0.001).

Conclusions

Burn depth, mechanism of injury and TBSA are always considered when developing the treatment and surgical management plan for patients with burns. This study identifies other factors influencing re-epithelialization, which can be controlled by the treating team, such as effective pain management and rapid referral to a specialized burn center, to achieve optimal outcomes.     

Dual-imaging system for burn depth diagnosis

Currently, determination of burn depth and healing outcomes has been limited to subjective assessment or a single modality, e.g., laser Doppler imaging. Such measures have proven less than ideal. Recent developments in other non-contact technologies such as optical coherence tomography (OCT) and pulse speckle imaging (PSI) offer the promise that an intelligent fusion of information across these modalities can improve visualization of burn regions thereby increasing the sensitivity of the diagnosis. In this work, we combined OCT and PSI images to classify the degree of burn (superficial, partial-thickness and full-thickness burns). Algorithms were developed to integrate and visualize skin structure (with and without burns) from the two modalities. We have completed the proposed initiatives by employing a porcine burn model and compiled results that attest to the utility of our proposed dual-modal fusion approach. Computer-derived data indicating the varying burn depths were validated through immunohistochemical analysis performed on burned skin tissue. The combined performance of OCT and PSI modalities provided an overall ROC-AUC = 0.87 (significant at p < 0.001) in classifying different burn types measured after 1-h of creating the burn wounds. Porcine model studies to assess feasibility of this dual-imaging system for wound tracking are underway.     

Contribution of thermal imaging in determining the depth of pediatric acute burns

BackgroundEarly burn wound assessment is a major problem in pediatrics. It involves regular clinical evaluations, and may be helped by objective tools, such as thermal imagers. Because of the skin temperature difference between partial and full thickness burns, due to injured vascular perfusion of the dermis in the latter, it could precisely identify areas with superficial burns which could heal from controlled wound healing, and those with deep burns which would need skin graft, at an early stage. The objective of this study was to assess the validity of the Flir one thermal imager® for this purpose.MethodsThermal images were obtained by a single observer three times after burn: day 1–3 (T1); day 4–7 (T2); day 8–10 (T3). ΔT (temperature difference between burned area and healthy skin) was calculated on a tablet with Flir One application. Validity was assessed by comparing ΔT obtained at each time between two groups at day 15 depending on the healing time of the burn wounds : before or after day 15. Primary outcome was the AUC (area under curve) of the ROC (Receiver operating characteristic) curve for ΔT at T1, T2 and T3, representing the ability of the Flir One Thermal Imager® to discriminate between a healing time <15 days and >15 days.Results40 patients were included (13 months to 13 years old). AUC at T1 and T2 are 0.700 (95% CI: 0.649; 0.925) and 0.787 (95% CI: 0.523; 0.877), respectively. AUC at T3 is 0.968 (95% CI: 0.918; 1.00). A ΔT threshold of −1.2 °C at T3 is associated with a specificity of 100% allowing to diagnose as of day 8 all the patients having deep burns which heal after 15 days.ConclusionsThe Flir One Thermal Imager® is an inexpensive, non-invasive, and easy-to-use device. It measures indirectly but with an excellent specificity the dermis perfusion reflecting the burns depth in children. However its low sensitivity calls for additional research to allow skin grafts earlier in common practice and decrease the length of stay.     

Temperature controlled burn generation system based on a CO2 laser and a silver halide fiber optic radiometer

BACKGROUND AND OBJECTIVES: Experimental animal study of burns is dependent on a reliable burn generation system. Most of the experimental systems used today are unable to produce precise partial thickness burns. This limits the ability to study minor changes associated with burn care. The aim of the study was to develop a method for generating burns with a fixed depth using a CO2 laser burn generation system. MATERIALS AND METHODS: The burn generation system was composed of two components: a burn generation device and a temperature sensing and control system. These components were designed to operate together in order to keep a constant, predetermined skin surface temperature during prolonged burn generation. One hundred thirty-eight spot burns were generated on the back of five shaved 450 g male Wistar rats. The rat skin was exposed to a 70 degrees C for 5-60 seconds. The burned areas were excised and underwent evaluation by hematoxylin-eosin-stained slide microscopy. RESULTS: A linear correlation was found between the duration of exposure and the average burn depth (r = 0.93). This correlation is represented by the equation: burn depth in millimeters = 0.012x (duration in seconds of skin exposure at 70 degrees C). CONCLUSIONS: The fiber-optic-controlled laser burn generation system studied is a reliable tool for creating partial thickness as well as full thickness skin burns in rats.     

Ultrasound assessed thickness of burn scars in association with laser Doppler imaging determined depth of burns in paediatric patients

This study describes the ultrasound assessment of burn scars in paediatric patients and the association of these scar thickness with laser Doppler imaging (LDI) determined burn depth. A total of 60 ultrasound scar assessments were conducted on 33 scars from 21 paediatric burn patients at 3, 6 and 9 months after-burn. The mean of peak scar thickness was 0.39 ± 0.032 cm, with the thickest at 6 months (0.40 ± 0.036 cm). There were 17 scald burn scars (0.34 ± 0.045 cm), 4 contact burn scars (0.61 ± 0.092 cm), and 10 flame burn scars (0.42 ± 0.058 cm). Each group of scars followed normal distributions. Twenty-three scars had original burns successfully scanned by LDI and various depths of burns were presented by different colours according to blood perfusion units (PU), with dark blue <125, light blue 125–250, and green 250–440 PU. The thickness of these scars was significantly different between the predominant colours of burns, with the thinnest scars for green coloured burns and the thickest for dark blue coloured burns. Within light blue burns, grafted burns healed with significantly thinner scars than non-grafted burns. This study indicates that LDI can be used for predicting the risk of hypertrophic scarring and for guiding burn care. To our knowledge, this is the first study to correlate the thickness of burns scars by ultrasound scan with burn depth determined by LDI.     

The optimal duration and delay of first aid treatment for deep partial thickness burn injuries

Using our porcine model of deep dermal partial thickness burn injury, various durations (10 min, 20 min, 30 min or 1 h) and delays (immediate, 10 min, 1 h, 3 h) of 15 °C running water first aid were applied to burns and compared to untreated controls. The subdermal temperatures were monitored during the treatment and wounds observed weekly for 6 weeks, for re-epithelialisation, wound surface area and cosmetic appearance. At 6 weeks after the burn, tissue biopsies were taken of the scar for histological analysis. Results showed that immediate application of cold running water for 20 min duration is associated with an improvement in re-epithelialisation over the first 2 weeks post-burn and decreased scar tissue at 6 weeks. First aid application of cold water for as little as 10 min duration or up to 1 h delay still provides benefit.     

Spectrophotometric intracutaneous analysis: a novel imaging technique in the assessment of acute burn depth

The noncontact spectrophotometric intracutaneous analysis scope (SIAscope) is a novel portable imaging device that rapidly produces images of the blood and melanin content of large areas of skin. The estimation of burn depth is often difficult in the clinical setting, and this pilot study was conducted to assess the potential for the SIAscope in aiding burn assessment. Nine patients with a variety of burn injuries had images taken of their acute burns within 48 hours of injury, both with a noncontact SIAscope and a laser Doppler perfusion imaging system (LDPI). Results showed that superficial partial thickness burns had increased hemoglobin and loss of melanin on SIAgraphs, whereas deep partial thickness burns had more pronounced hemoglobin concentrations and apparent melanin increases, helping to differentiate these 2 burn types. The SIAscope, a relatively inexpensive, portable device, has the potential to be a highly useful clinical adjunct in the bedside estimation of acute burn depth.     

Successful prevention of secondary burn progression using infliximab hydrogel: A murine model

IntroductionBurn injury remains a serious cause of morbidity and mortality worldwide. Severity of burns is determined by the percentage of burned area compared to the body surface area, age of patient, and by the depth of skin and soft tissue involvement; these factors determine management as well as prospective outcomes. The pathophysiology of partial- to full-thickness burn conversion remains poorly understood and is associated with a worse overall prognosis. Recent studies have demonstrated that an altered inflammatory response may play a significant role in this conversion and therefore a reduction in early inflammation is crucial to ultimately decreasing burn severity and morbidity. We hypothesize that the application of a microcapillary gelatin–alginate hydrogel loaded with anti-TNF-α (infliximab) monoclonal antibodies to a partial-thickness burn will reduce inflammation within partially burned skin and prevent further progression to a full-thickness burn.MethodsAssembly of the microfluidic hydrogels is achieved by embedding microfibers within a hydrogel scaffold composed of a gelatin–alginate blend, which is then soaked in a solution containing anti-TNF-α antibodies for drug loading. 12 young (2–4 months) and 12 old (>16 months) mice were given partial thickness burns. The treatment cohort received the anti-TNF-α infused hydrogel with an occlusive dressing and the control cohort only received an occlusive dressing. Mice were euthanized at post-burn day 3 and skin samples were taken. Burn depth was evaluated using Vimentin immunostaining.ResultsAll mice in the treatment cohort demonstrated decreased conversion of burn from partial to full thickness injury (old = p < 0.01, young = p < 0.001) as compared to the control group. Old mice had greater depth of burn than young mice (p < 0.001). There were greater eosinophils in the treatment cohort for both young and old mice, but it did not reach statistical significance.ConclusionThe application of a novel microcapillary gelatin–alginate hydrogel infused with anti-TNF-α antibody to partial thickness burns in mice showed reduction in partial to full thickness burn secondary progression as compared to controls using this murine model; this promising finding might help decrease the high morbidity and mortality associated with burn injuries.     

The boiled potato peel as a burn wound dressing: a preliminary report

This paper discusses the suitability of potato peel as a burn wound dressing in developing countries. Clinical trials have demonstrated that epithelial growth occurs under the potato peel dressing in superficial partial thickness skin loss burns. In deep partial, full skin thickness burns and in the late granulating burn wound the results are not so favourable. More experience is required.     

Assessment of burn depth: a prospective, blinded comparison of laser Doppler imaging and videomicroscopy

INTRODUCTION AND AIMS: There is a need, both in clinical and research settings, for an affordable, objective method of assessing burn depth. This study compares burn depth assessment by videomicroscopy with laser Doppler imaging (LDI) in patients with dermal burns. The videomicroscope is inexpensive compared to LDI, and can visualise the dermal capillary structure, therefore potentially allowing objective assessment of dermal burn injuries. METHODS: Patients admitted <72 h post-injury were included in the trial. Blinded LDI and videomicroscopy assessments were carried out. The patients were then followed up to one of three end-points: primary healing without surgery; early surgery; delayed healing and subsequent split skin grafting. The incidence of infection was also noted. RESULTS: Twenty-seven burn wounds were examined. In superficial partial thickness injuries, the videomicroscope reliably demonstrated an intact or nearly intact dermal vascular structure, progressing through to large amounts of capillary destruction and haemoglobin deposition in deep partial thickness injuries and complete destruction in full thickness injuries. The videomicroscope findings correlated strongly with both those of the LDI (p<0.001) and with clinical outcome (p<0.001). DISCUSSION: The videomicroscope is capable of accurately and objectively assessing burn depth. The results correlated well with both the clinical outcome and the laser Doppler findings. In addition, videomicroscopy is significantly cheaper than LDI and avoids several of the disadvantages of LDI.     

Epidemiology of outpatient burns in Tehran: An analysis of 4813 cases

This study aims to demonstrate the epidemiologic characteristics of outpatient burn injuries in Tehran. This cross-sectional study was performed over a 1-year period in a referral burn centre in Tehran and included all outpatient burns. The required data were recorded by two trained physicians. Of the 4813 studied patients, including 293 infants, 2901 patients (60%) were male (P < 0.001). The mean age of the adult patients was 31.3 ± 18.3 years, while for infants it was 10.68 ± 2.27 months. In all age groups and both genders, scalding was the most common aetiology. Majority of the burns were non-intentianal (n = 4808) and 70.5% of the injuries occurred at home. Housewives consisted of 24% of the burn patients. With respect to the site of burn, multiple injuries were the most frequent (53%) followed by upper extremities (37%). Most of the burns (96%) were partial thickness. Significant association was present between the aetiology and depth of burn (P < 0.001). The mean affected total body surface area (TBSA) was 3.16 ± 2.92% and there was significant association between burnt TBSA and the mechanism of injury (P < 0.001). In conclusion, it seems that women aged 21–30 years and children younger than 10 years are at greater risk of these injuries and therefore should be the target for preventive strategies.     

Use of Suprathel for partial thickness burns in children

We evaluated the use of Suprathel^®, a synthetic skin substitute, for partial thickness burns in children. Thirty-three children (20 females, 13 males; mean age 29 months, range 5 months to 11 years) with burns were treated with Suprathel^®. The burns were superficial partial thickness (n = 24) or mid-dermal (n = 19); the median %TBSA was 4% (range 1–13%).     

Accuracy of early burn depth assessment by laser Doppler imaging on different days post burn

Background

Accurate diagnosis of burn depth is essential in selecting the most appropriate treatment. Early assessment of burn depth by clinical means only has been shown to be inaccurate, resulting in unnecessary operations or delay of grafting procedures. Laser Doppler imaging (LDI) was reported as an objective technique to determine the depth of a burn wound, but the accuracy on very early days post burn has never been investigated yet.

Methods

In 40 patients with intermediate depth burns, we prospectively evaluated and compared the accuracy of the LDI measurements with the clinical assessments on days 0, 1, 3, 5, 8. Clinical evaluation of the depth of the burn was performed by two observers blinded to the LDI images. Accuracies were assessed by comparison with outcome: healing times longer than 21 days were considered to be equivalent to a biopsy finding of a deep dermal wound. Obviously superficial and full thickness wounds were excluded. LDI flux level was used for LDI prediction of outcome: less than 220 PU to predict non-healing at day 21.

Results

The accuracies of burn depth assessments on the day of burn and post burn days 0, 1, 3, 5 and 8 using LDI were 54%, 79.5%, 95%, 97% and 100% compared with clinical assessment accuracies of 40.6%, 61.5%, 52.5%, 71.4% and 100%, respectively. LDI accuracy was significantly higher than clinical accuracy on day 3 (p < 0.001) and day 5 (p = 0.005). Burn depth conversion was also considered. This is the first study to quantify the advantage of LDI scanning over clinical assessments during these important early after burn days.     

Apoptotic death in deep partial thickness burns vs. normal skin of burned patients

BACKGROUND: Deep partial thickness burns have an ambiguous behavior evolving either into spontaneous healing or full thickness burns. The aim of this study was to investigate these lesions for the presence of apoptosis thereby giving a possible cellular explanation to their peculiar clinical progression. METHODS: We used colocalization of DNA fragments (terminal deoxynucleotidyl transferase mediated dUTP nick end labeling) and Fas ligand CD95 antibodies to calculate the apoptotic rate of deep partial thickness burns and normal skin in 21 patients after acute thermal injuries (significant difference considered: P < 0.05). RESULTS: Deep partial thickness burns were associated with a higher apoptotic rate than normal skin (48.15% +/- 17.22% versus 18.6% +/- 7.2%; P = 0.0002). There were no apparent significant correlations of apoptotic rate with age, days from injury, total burn surface area or deep burn area except for a slight correlation with sex (r = 0.484; P = 0.02). CONCLUSIONS: A higher apoptotic rate was present in dermal cells of deep partial thickness burns if compared to that of the unburned skin. These data would suggest that deep partial thickness progression derive from apoptosis. Specific studies are required to confirm this hypothesis and to investigate its clinical and therapeutic significance.     

Functional late outgrowth endothelial progenitors isolated from peripheral blood of burned patients

Background

Bioengineered skin substitutes are increasingly considered as a useful option for the treatment of full thickness burn injury. Their viability following grafting can be enhanced by seeding the skin substitute with late outgrowth endothelial progenitor cells (EPCs). However, it is not known whether autologous EPCs can be obtained from burned patients shortly after injury.

Methods

Late outgrowth EPCs were isolated from peripheral blood sampled obtained from 10 burned patients (extent 19.6 ± 10.3% TBSA) within the first 24 h of hospital admission, and from 7 healthy subjects. Late outgrowth EPCs were phenotyped in vitro.

Results

In comparison with similar cells obtained from healthy subjects, growing colonies from burned patients yielded a higher percentage of EPC clones (46 versus 17%, p = 0.013). Furthermore, EPCs from burned patients secreted more vascular endothelial growth factor (VEGF) into the culture medium than did their counterparts from healthy subjects (85.8 ± 56.2 versus 17.6 ± 14 pg/mg protein, p = 0.018). When injected to athymic nude mice 6 h after unilateral ligation of the femoral artery, EPCs from both groups of subjects greatly accelerated the reperfusion of the ischaemic hindlimb and increased the number of vascular smooth muscle cells.

Conclusions

The present study supports that, in patients with burns of moderate extension, it is feasible to obtain functional autologous late outgrowth EPCs from peripheral blood. These results constitute a strong incentive to pursue approaches based on using autotransplantation of these cells to improve the therapy of full thickness burns.     

A comparative study of 1% silver sulphadiazine (Flammazine) versus an enzyme alginogel (Flaminal) in the treatment of partial thickness burns

Introduction

In the conservative treatment of burns, rapid wound healing is desirable to obtain good a esthetic and functional results. The aim of this study was to compare the efficacy of 1% Silversulfadiazine (SSD/Flammazine^®) and an enzyme alginogel (Flaminal^® or Flaminal^® Forte) on the healing of superficial and intermediate partial thickness burns.

Methods

In this retrospective cohort study comparable burn wounds treated with Flaminal^® or with 1% SSD were included. Outcome parameters included: length of hospital stay, bacterial burden and time to wound closure. Significance was tested using SPSS package.

Results

44 wounds in the Flaminal^® group, and 39 wounds in the 1% SSD group were included. Wounds treated with Flaminal^® showed a significantly higher bacterial load (p = 0.024) and contained significantly more bacterial species (p = 0.010) but showed a significantly shorter healing time of 17 vs. 24 days (p < 0.0001).

Conclusion

A significantly shorter healing time was demonstrated in partial thickness burn wounds treated with Flaminal^® versus 1% SSD, which may lead to a shorter length of hospital stay and better scar quality. The possibility of accurate burn depth assessment and the results in this study corroborate the change in treatment protocol made in the year 2000 when we switched from 1% SSD to Flaminal^®.     

Evaluation of hyperspectral imaging as a modern aid in clinical assessment of burn wounds of the upper extremity

The most common burn wound assessment continues to be the clinical inspection and the tactile examination, which are subjective and remain challenging even for experienced burn surgeons. Recently, hyperspectral imaging camera systems have been increasingly used to support the evaluation of burn wounds. The aim of our study was to determine if hyperspectral imaging analysis differentiates and objectifies the assessment of burn wounds in burns of the upper extremities.We included 97 superficial partial, deep partial dermal burns, and full thickness burns. Hyperspectral imaging analysis was performed for all burns using proprietary software. The software recorded parameters for tissue oxygenation (StO2), tissue hemoglobin index, and near-infrared perfusion. These values were compared with the recordings for healthy, non-burned skin.We found that hyperspectral imaging analysis effectively differentiates burn wounds and shows the ability to distinguish even superficial partial burns from deep partial burns in the near-infrared perfusion analysis feature. Although, it was not possible to differentiate burn wounds in all features.Currently, it is important to optimize the respective reference values of the individual burn degrees for an objectified assessment.     

Dermal substitution with Matriderm in burns on the dorsum of the hand

Background

Dermal substitutes are used increasingly in deep partial and full-thickness burn wounds in order to enhance elasticity and pliability. In particular, the dorsum of the hand is an area requiring extraordinary mobility for full range of motion. The aim of this comparative study was to evaluate intra-individual outcomes among patients with full-thickness burns of the dorsum of both hands. One hand was treated with split-thickness skin grafts (STSG) alone, and the other with the dermal substitute Matriderm^® and split-thickness skin grafts.

Material and Methods

In this study 36 burn wounds of the complete dorsum of both hands in 18 patients with severe burns (age 45.1 ± 17.4 years, 43.8 ± 11.8% TBSA) were treated with the simultaneous application of Matriderm^®, a bovine based collagen I, III, V and elastin-hydrolysate based dermal substitute, and split-thickness skin grafting (STSG) in the form of sheets on one hand, and STSG in the form of sheets alone on the other hand. The study was designed as a prospective comparative study. Using both objective and subjective assessments, data were collected at one week and 6 months after surgery. The following parameters were included: After one week all wounds were assessed for autograft survival. Skin quality was measured 6 months postoperatively using the Vancouver Burn Skin Score (VBSS). Range of motion was measured by Finger-Tip-Palmar-Crease-Distance (FPD) and Finger-Nail-Table-Distance (FNTD).

Results

Autograft survival was not altered by simultaneous application of the dermal matrix (p > 0.05). The VBSS demonstrated a significant increase in skin quality in the group with dermal substitutes (p = 0.02) compared to the control group with non-substituted wounds. Range of motion was significantly improved in the group treated with the dermal substitute (p = 0.04).

Conclusion

From our results it can be concluded that simultaneous use of Matriderm^® and STSG is safe and feasible, leading to significantly better results in respect to skin quality of the dorsum of the hand and range of motion of the fingers. Skin elasticity was significantly improved by the collagen/elastin dermal substitute in combination with sheet-autografts.