Wireless microcurrent stimulation improves blood flow in burn wounds.

RATIONALE: Skin breakdown, as in wounds, leads to an electric potential, defined as current of injury with the intent of wound closure. Burn wounds are defined by different zones of perfusion having a direct influence on further therapy (e.g. conservative management or skin grafting). We studied immediate, quantifiable effects of electric stimulation on skin perfusion in burn wounds. METHOD: Wireless Microcurrent Stimulation (WMCS) was utilised as an adjunct therapeutic modality in 10 patients with partial thickness burn wounds. Microcirculation in the skin was quantified with a Laser Doppler (LDI) before and after WMCS treatment. We included a control group of 10 healthy individuals. RESULTS: A single application of WMCS significantly increased mean flow, velocity and subsequently, haemoglobin and oxygen saturation in partial thickness burn wounds. In healthy skin these parameters increased, but were far less pronounced than in thermally injured skin. CONCLUSION: This study revealed, for the first time that non-contact WMCS improves blood flow in critically perfused partial thickness burn wounds without disturbing the wound or systemically affecting the patient and may represent a promising adjunct tool in burn treatment, with the potential of faster healing by enhanced perfusion of burn wounds and reduction of the zone of stasis. LEVEL OF EVIDENCE: III.

Impact of scapholunate dissociation on human wrist kinematics.

Neither the complex motions of the scapholunate joint, nor the kinematic changes that occur as a result of injury to it, are fully understood. We used electromagnetic tracking within affected bones to evaluate the physiologic motions in the planes of flexion and extension, and of radial and ulnar deviation of human cadaver wrists, before and after complete transection of the scapholunate ligaments. Despite individual variance between each wrist, we were able to establish a pattern in the changes that occurred after scapholunate ligament injury. During the motions examined, the scaphoid showed an increase in translational deviation in almost all motion axes. In contrast, the movement of the lunate seemed to be impaired, especially in radial-ulnar deviation.

Evaluation of facial blood flow using three-dimensional scanning.

The Vectra X3 3-dimensional face scanner allows us to visualise the erythema of superficial layers of skin in addition to its regular scanning functions. The aim of our study was to find out whether changes we provoked in the circulation of the skin would be registered and displayed by the face scanner. We measured the circulation in the skin of the cheeks of 20 volunteers with a face scanner, a laser Doppler device, and a skin pigmentation analyser before and after the application of a nitric oxide cream. The results were compared in terms of grey tones, local concentrations of haemoglobin, and erythema. All methods showed significant changes (p<0.001) before and after application of the cream. The study proved that the Vectra X3 recognises changes in skin circulation and displays them in a simple and evident way.

Necrotizing fasciitis resulting in fatal lung aspergillosis: Uncommon pathogenesis. A case report.

We present a fatal case of Aspergillus-associated lung failure in a patient with necrotizing fasciitis. The cause of the fasciitis was a retroperitoneal perforation of a colon carcinoma. Being already a rare condition, the fasciitis did not manifest as Fournier's gangrene like similar described cases illustrate, but instead travelled along the fasciae and subcutaneous fat tissue cranially into the thoracic cavity, ultimately leading to a disseminated infection of the lungs. The lethal outcome was thus caused by respiratory failure at a time when the primary focus was already successfully treated, contrary to typical cases of necrotizing fasciitis. This case report depicts the importance of acknowledging opportunistic fungal infections in the practice of emergency surgery. Contributing factors, pathogenesis and possible prevention measures are discussed.

Two-component collagen nerve guides support axonal regeneration in the rat peripheral nerve injury model.

Progress in material development has enabled the production of nerve guides that increasingly resemble the characteristics of an autologous nerve graft. In the present study, 20 mm adult rat sciatic nerve defects were bridged with the collagen-based, two-component nerve guide 'Neuromaix', the commercially available NeuraGen® nerve tube or an autologous nerve graft. Neuromaix was able to support structural as well as functional regeneration across this gap. The majority of the axons grew across the scaffold into the distal nerve segment and retrograde tracing confirmed that these axons were of somatosensory and motor origin. Histomorphology revealed that axons regenerating through Neuromaix exhibited reduced myelin sheath thickness, whereas axon diameter and axon density were comparable to those of the autograft. Neuromaix implantation resulted in reinnervation of the gastrocnemius muscle to a level that was not significantly different from that supported by the autograft, as demonstrated by electrophysiology. Our findings show that the use of the Neuromaix scaffold not only allowed axonal regeneration across large nerve gaps, but that the regenerating axons were also able to functionally reinnervate the muscles. These data provide a promising perspective for the first in human application of the materials. Copyright © 2016 John Wiley & Sons, Ltd.

[Registry Research Funding of the German Society of Plastic, Reconstructive and Aesthetic Surgeons (DGPRÄC) and Research Funding Report 2015/2016]. / Register Forschungsförderung der Deutschen Gesellschaft der Plastischen, Rekonstruktiven und Ästhetischen Chirurgen (DGPRÄC) und Forschungsförderungs-Bericht 2015/2016.

In addition to the impact factor, research funding also plays a central role in evaluating the academic performance and quality of a researcher, a clinic or a surgical specialty. The scope and quality of research in Plastic Surgery are usually very little known, so that even large funding institutions do not get a full view of research funding in our specialty. Therefore, sometimes traditional structures are not adapted to new needs by the developing younger surgical fields. In peer review sometimes peers are not chosen from the same surgical specialty, but from a different surgical fields being peers in large field of surgery. By this a bias can easily be generated which would not be advantageous for subspecialties such Plastic Surgery. The goal of this paper is to establish an overview in the form of a registry of the German Society of Plastic Reconstructive and Aesthetic Surgeons (DGPRÄC) in order to make the joint academic achievements more visible in the future. At the same time, a research funding report is to be published for the years 2015 and 2016.

[Current Perceptions of Lipofilling on the Basis of the New Guideline on "Autologous Fat Grafting"]. / Aktuelle Erkenntnisse zur Eigenfett Transplantation anhand der neuen Leitlinie "Autologe Fetttransplantation".

Introduction: Autologous fat transfer has recently become an increasingly popular surgical procedure and comprises harvesting, processing and transplantation of adipose tissue, as well as professional follow-up care. This method, as a surgical procedure, can be utilised for trauma-, disease- or age-related soft tissue volume deficits and soft tissue augmentation. As usage is increasing, but the variables of fat harvest, specific indications and fashion of fat transfer are poorly defined, there is a great demand for development of a guideline in the field of reconstructive and aesthetic surgery. Methods: All relevant points were discussed within the scope of a consensus conference including a nominal group process of all societies involved in the procedure and ratified with a strong consensus (>95%). Literature from the standard medical databases over the last 10 years was retrieved, studied and specific guidelines were concluded. Results: Consensus was achieved among all professionals involved on the following points: 1. definition 2. indication/contraindication, 3. preoperative measures 4. donor sites 5. techniques of processing 6. transplantation 7. follow-up care 8. storage 9. efficacy 10. documentation 11. evaluation of patient safety. Conclusion: Definite indications and professional expertise are paramount for autologous fat tissue transfer. Successful transfers are based on the use of correct methods as well as specific instruments and materials. Autologous adipose tissue transplantation is considered to be a safe procedure in reconstructive and aesthetic surgery, due to the low rate of postoperative complications and sequelae.

Early Functional Treatment and Modern Cast Making for Indications in Hand Surgery.

Cast treatment can serve both as a nonsurgical treatment option and as a means for providing postoperative protection. However, with the duration of immobilization intervals, the benefits of cast treatment, especially in hand surgery, are at risk of being outweighed by undesired drawbacks such as joint stiffening and contracture formation. In order to minimize potential complications commonly associated with cast treatment, efforts to further improve cast making must attempt to reconcile two conflicting objectives: (1) to achieve stability and rigidity at the site of injury (e.g., fracture retention) and (2) to allow free range of joint movement as early as possible. In addition, in order to assure patient compliance, modern cast treatments should aim to improve wearing-comfort of the cast. This paper describes modern cast designs for four common types hand injuries, with sample cases highlighting the clinical outcome of each treatment.

[Research Assessment in Plastic and Reconstructive Surgery on a National Level: A 5-Years Systematic Review of Research Activity in German University Hospitals]. / Eine Analyse der Forschungsaktivität universitärer Kliniken für Plastische Chirurgie im nationalen Vergleich: Eine systematische 5-Jahres Evaluation der Forschungsaktivität in Deutschland.

BACKGROUND: In plastic surgery, a broad spectrum of research activity has been performed over the past decade. However, compared with other medical fields, there seems to be a lack of central coordination in the individual research areas. Also no comprehensive, periodical assessment has been undertaken to date. This study aims to provide an overview of German research activity in plastic surgery departments affiliated to medical universities. METHODS: We performed a 5-year interval (01/2010-12/2014) survey of PubMed-listed publications of plastic surgery departments in German university hospitals. For each university (n=11), statistical analyses of the following parameters were performed: distribution of research fields, number of publications, annual cumulative impact sum (IS) and impact factor (IF). RESULTS: For the above-mentioned period, a total of n=904 publications were analysed. Ranking among academic departments was as follows: number of publications: 1. Medizinische Hochschule Hannover 178 (annual average x̅=36/median x͂=34; 2. University Hospital of Erlangen 115 (x̅=23/x͂=23); 3. Bergmannsheil Bochum 90 (x̅=18/x͂=19). The annual impact sum (IS) averaged 33.51 (SD 11.088, p<0.05); separated IS: 1. Medizinische Hochschule Hannover x̅=74.66, x͂=62.22, 2. University Hospital of Erlangen x̅=53.24, x͂=50.84, 3. University Hospital RWTH Aachen x̅=46.12, x͂=44.67. The average impact factor per publication was: 1.98 (SD 0.31, p<0.05); separated IF: 1. University Hospital RWTH Aachen x̅=2.76, x͂=2.79; 2. University Hospital of Erlangen x̅=2.34, x͂=2.46; 3. Medizinische Hochschule Hannover x̅=2.08, x͂=2.05. The analysed publications were distributed as follows: 43% reviews, 20% cell biology/tissue engineering, 10% reconstruction, 27% others (including wound healing, vessel/nerve research, hand surgery, burn, aesthetics, oncology). CONCLUSION: Based on this comprehensive analysis, it seems that a periodical assessment of current research activity would be useful for the future. Data assessments should be started on European and international levels and should also be applied to other surgical and medical disciplines.

Extensive burn injury caused by fundamental electronic cigarette design flaw.

Currently, electronic cigarette (EC) devices are widely used as an alternative to conventional smoking. The underlying technical principle is an electric coil-based vaporizer unit, which vaporizes various solutions for inhalation purposes with a rechargeable lithium battery unit as power source. We report a case of extensive burn injury resulting from the thermal explosion of a battery unit within an EC device. Though internal thermal instabilities of lithium ion batteries are a known safety issue, the unique feature here is a pronounced amplification of the extent of burn injury due to an additional scalding burn mechanism that resulted from heating of the liquid reservoir adjacent to the battery. Thus, we demonstrate a relevant design flaw in various EC devices, which in the authors' opinion needs to be addressed both by manufacturers and safety regulations.

Les cigarettes électroniques sont de nos jours très largement utilisées comme alternative au tabagisme. Le principe est la vaporisation aux fins d'inhalation d'un liquide chauffé par une résistance alimentée par une batterie au lithium, rechargeable. Nous rapportons un cas de brûlure étendue causée par l'explosion de la batterie, surchauffée. Si le risque d'explosion des batteries au lithium est bien connu en cas de surchauffe, la particularité ici est que le patient a en outre été ébouillanté par le e-liquide dont le réservoir était très proche de la batterie. Nous montrons ici un défaut de conception de certaines cigarettes électroniques qui devrait être pris en compte par les fabricants et les autorités.

Efficient bridging of 20 mm rat sciatic nerve lesions with a longitudinally micro-structured collagen scaffold.

An increasing number of biomaterial nerve guides has been developed that await direct comparative testing with the 'gold-standard' autologous nerve graft in functional repair of peripheral nerve defects. In the present study, 20 mm rat sciatic nerve defects were bridged with either a collagen-based micro-structured nerve guide (Perimaix) or an autologous nerve graft. Axons regenerated well into the Perimaix scaffold and, the majority of these axons grew across the 20 mm defect into the distal nerve segment. In fact, both the total axon number and the number of retrogradely traced somatosensory and motor neurons extending their axons across the implant was similar between Perimaix and autologous nerve graft groups. Implantation of Schwann cell-seeded Perimaix scaffolds provided only a beneficial effect on myelination within the scaffold. Functional recovery supported by the implanted, non-seeded Perimaix scaffold was as good as that observed after the autologous nerve graft, despite the presence of thinner myelin sheaths in the Perimaix implanted nerves. These findings support the potential of the Perimaix collagen scaffold as a future off-the-shelf device for clinical applications in selected cases of traumatic peripheral nerve injury.

[In Vitro and In Vivo Biocompatibility of a Novel, 3-Dimensional Cellulose Matrix Structure]. / In vitro und in vivo Biokompatibilität einer neuartigen, 3-dimensionalen Cellulose-Matrixstruktur.

BACKGROUND: Biological and physical characteristics of matrices are one essential factor in creating bioartificial tissue. In this study, a new 3-dimensional cellulose matrix (Xellulin(®)) was tested in terms of biocompatibility and applicability for tissue engineering in vitro and in vivo. MATERIALS AND METHODS: The tested matrix Xellulin(®) is a natural hydrological gel-matrix containing bacterial cellulose and water. To evaluate the cell biocompatibilty, cell adherence and proliferation characteristics in vitro, the matrix was cultured with human fibroblasts. Further in vivo studies were carried out by transplanting preadipocytes of 4- to 6-week-old Wistar rats with 3 different conditions: a) Xellulin(®) including 500 000 preadipocytes subcutaneous, b) Xellulin(®) including 500 000 preadipocytes within an in vivo bioreactor chamber, c) Xellulin(®) without cells subcutaneous as control. After explantation on day 14 histomorphological and immunohistochemical evaluations were performed. RESULTS: In vitro study revealed an excellent biocompatibility with good cell adherence of the fibroblasts on the matrix and evidence of cell proliferation and creation of a 3-dimensional cell network. In vivo neocapillarisation could be shown in all groups with evidence of erythrocytes (H/E staining) and endothelial vascular cells (RECA-1-staining). A significantly higher vascular density was shown in vascularised bioreactor group (18.4 vessels/100 000 µm(2) (group b) vs. 8.1 (group a), p<0.05). Cell density was the highest in the vascularised group, but without significant values. No immunogenic reaction to the matrix was noticed. DISCUSSION: The promising in vitro results concerning cell adherence and proliferation on the tested matrix could be confirmed in vivo with an evidence of 3-dimensional neocapillarisation. Cell survival was higher in the vascularised group, but without significance. Long-term tests (28-42 days) need to be carried out to evaluate long-term cell survival and the matrix stability. Furthermore, studies concerning the implementation of the matrix within anatomic structures as well as long-term biocompatibility are needed.

L-arginine and arginine ethyl ester enhance proliferation of endothelial cells and preadipocytes - how an arginine ethyl ester-releasing biomaterial could support endothelial cell growth in tissue engineering.

Adipose tissue engineering is a promising solution for the reconstruction of soft tissue defects. An insufficient neovascularisation within the scaffolds that leads to necrosis and tissue loss is still a major shortcoming of current tissue engineering attempts. Biomaterials, which release angiogenic factors such as L-arginine, could overcome this challenge by supporting the neovascularisation of the constructs. L-arginine is insoluble in organic solvents and thus cannot be incorporated into commonly used polymers in contrast to its ethyl ester. Here, we compared the effects of arginine and its ethyl ester on endothelial cells and preadipocytes, and generated an arginine ethyl ester-releasing, angiogenic polymer. We cultivated adipose tissue-derived endothelial cells and preadipocytes in arginine-free medium supplemented with L-arginine or L-arginine ethyl ester and assayed the proliferation rate and the degree of adipogenic differentiation, respectively. Additionally, we prepared arginine ethyl ester-releasing poly(D,L-lactide) foils, and investigated their impact on endothelial cell proliferation. We could demonstrate that arginine ethyl ester like arginine significantly increased the proliferation of endothelial cells and preadipocytes without inhibiting an induced adipogenic conversion of the preadipocytes. Further, we could show that the arginine ethyl ester-releasing polymer significantly increased endothelial cell growth. The present data are helpful guidance for generating angiogenic biomaterials that promote endothelial cell growth, and thereby could support neovascularisation within tissue engineering approaches.

Management, clinical outcomes, and complications of acute cannula-related peripheral vein phlebitis of the upper extremity: A retrospective study.

OBJECTIVE: Acute phlebitis due to peripheral vein catheter use is frequently observed in clinical practice, and requires surgical therapy in severe cases. In this retrospective study, we aimed to increase awareness, evaluate current treatment options, and develop recommendations to optimize treatment outcomes. METHODS: A total of 240 hospitalized patients with a diagnosis of upper extremity phlebitis from 2006 to 2011 were evaluated in terms of initial clinical features, parameters, co-morbidities and treatment regimes. Severity of phlebitis was graded according to the Baxter scale by assessing clinical symptoms such as pain, erythema, induration, swelling, or palpable venous cord (grade 0-5). Patients were divided in two subgroups: conservative (n = 132) and operative (n = 108) treatment. RESULTS: Surgical intervention rates and severity were higher for cannula insertion in the cubital fossa region than for cannula insertion in the forearm and hand region (p < 0.05). Baxter scale grades were higher in the surgical treatment group than in the conservative treatment group (4.47 vs. 2.67, respectively). CONCLUSIONS: The cubital fossa region is vulnerable to severe phlebitis and is not recommended as the first site of choice for cannulation. Phlebitis of Baxter scale grade 4 or 5 should be considered for early surgical intervention.

Improvement of facial scar appearance and microcirculation by autologous lipofilling.

BACKGROUND: Autologous lipofilling has become a standard procedure for many indications in plastic surgery. Single-case studies have reported improvements in scars, especially in burn patients, after autologous lipofilling. Despite its widespread use, little is known about the mechanisms responsible for this improvement. It is hypothesized that the mesenchymal stem cells and numerous growth factors contained in the lipoaspirate contribute to the skin and scar remodeling. MATERIAL AND METHODS: Between 2008 and 2012, 35 facial scars (n=35) on 26 patients (n=26) were treated by autologous lipofilling. The preoperative examinations and postoperative follow-up included use of the patient and observer scar assessment scale (POSAS), photo documentation, and laser Doppler spectrometry (O2C) measurements of tissue oxygen saturation, hemoglobin levels, and microcirculation on the second, seventh, and ninetieth postoperative days. RESULTS: The scar quality improved in all cases, leading to a high patient satisfaction rate at the final follow-up examination. The POSAS scores were significantly increased for pain (p=0.0331), color (p=0.0007), stiffness (p=0.0030), irregularity (p=0.0039), pigmentation (p=0.0282), and pliability (p=0.0404). In addition, we observed increased hemoglobin levels in the early postoperative period (second day) and a reduction in the microcirculation, which normalized to the preoperative values after 7-90 days. CONCLUSIONS: We demonstrated that autologous lipofilling represents a valuable technique for the treatment of facial scars. Further prospective observational studies are needed to better understand the mechanisms leading to scar enhancement and to make this procedure more reliable and predictable for patients.

[Biomechanical modelling of the wrist joint]. / Biomechanische Modellierung der Handwurzel.

BACKGROUND: The hand represents one of the most complex joint mechanisms of the human body. The hand is also an important communication medium. The spectrum of today's hand injuries reaches from minor damage up to complex traumata with loss of several functional aspects. Enormous subsequent economic costs result. The therapeutic re-establishment of the equilibrium between maximum stress and the actual applied stress is the condition for a lifelong joint function. MATERIAL AND METHODS: A literature review about biomechanical wrist models was realised. The previous models found in the literature were systematically analysed as well as verifying their suitability for clinical use regarding pathological changes, therapy approaches and modelling/simulation approaches, respectively, of wrist injuries. RESULTS: The return of the wrist joint biomechanics to the normal condition is a key factor for a successful therapy. Furthermore, it is important for the re-establishment of an unimpaired joint function. Currently, there exist only simplified descriptions and models of the wrist joint, approximated by technical joints and furthermore, they are partially contradictory. Therefore, no uniform validated biomechanical wrist model exists as yet. CONCLUSION: Regarding the arising complex clinical problems, however, a valid biomechanical wrist joint model would be necessary as assistance, in order to improve the success of systematised therapies on the basis of computer-aided model-based planning and intervention.

The lipo-facelift: merging the face-lift and liposculpture: eight years experience and a preliminary observational study.

BACKGROUND: Since the introduction of the classic submucosal aponeurotic system (SMAS) face-lift, the surgical approach to improve the changes of an aging face has evolved, and significant technical improvements have been made. However, several problems still have not been solved satisfactorily. These problems include facial lipodystrophy and changes in skin and skin texture. METHODS: The Lipo-Facelift procedure consists of facial liposculpturing performed simultaneously with a biplanar, bivectorial SMAS face-lift procedure. The authors analyzed pre- and postsurgical photographs of 12 patients with a Lipo-Facelift after 3 and 12 months and analyzed their charts for complications. Furthermore, O2C measurement was performed to assess improved microcirculation. The longest follow-up period was 8 years. RESULTS: The Lipo-Facelift demonstrated very satisfying results. Initial swelling and bruising were seen as well as two cases of wound-healing disorders, but no surgical intervention or revision was needed. The findings show lasting improvement of skin quality and a youthful appearance. CONCLUSION: The Lipo-Facelift corrects age-related skin and SMAS changes as well as age-related lipodystrophy, improves skin circulation and skin revitalization, and provides a lasting and natural result. The skin quality resulting from simultaneous lipofilling can be explained by improved angiogenesis due to transferred growth factors in the lipoaspirate. Also, differentiation of progenitor cells to fibroblasts and increased production of collagen contribute to firmer skin. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

A rare case of massive carpal osteoblastoma requiring complex reconstructive surgery.

An osteoblastoma is a rare, commonly benign, osteoid-producing neoplasm of the bone with an incidence of 2% of all primary bone tumours. We present a case of a 54-year-old patient with persisting carpal pain and massive swelling of the hand for a period of 4 years. Incision biopsies revealed the histopathological finding of a carpal osteoblastoma. After complete tumour excision, including the carpal and, in parts, metacarpal bones, reconstructive surgery was performed with a free osteocutaneous iliac crest flap to obtain a natural hand contour and the best possible hand function. Follow-up revealed improvement of the hand function in terms of flexion, extension and strength without discomfort or further pain. Thus, ongoing carpal pain should lead to an intensive search with further diagnostic measures such as magnetic resonance imaging (MRI) scan as well as biopsies, if necessary, to obtain the correct diagnosis.

Micro-punch technique for treatment of Fordyce spots: a surgical approach for an unpleasant condition of the male genital.

Fordyce spots are ectopic sebaceous glands, ranging between 2 and 3 mm in diameter. These benign lesions are most frequently located in the oral mucosa and the genital skin. Especially in the male genital region they can cause itching, discomfort during sexual activities and are aesthetically unpleasant. So far, a variety of therapeutic procedures have been reported with varying success and recurrence rates. In the present retrospective study (n = 23 patients between 2003 and 2011), we present our surgical approach by means of the micro-punch technique. Using this effective method, we achieved very satisfactory functional and cosmetic results. There were no signs of recurrence during postoperative observations from 12 up to 84 months (median = 51.3 months).

Randomised, controlled pilot to compare collagen and foam in stagnating pressure ulcers.

OBJECTIVE: To compare the clinical efficacy of a collagen dressing covered with a foam dressing with the same foam used as a primary dressing in stagnating granulating pressure ulcer patients. METHOD: Patients were randomised to receive either a foam dressing (Suprasorb P; Lohmann & Rauscher) as a primary dressing (group A), or a combination of a collagen dressing (Suprasorb C; Lohmann & Rauscher) covered with the same foam dressing (group B).Wound fluid was collected and evaluated prior to treatment (day 0), and on days 3,7, 14 and 21 .The level and expression of matrix metalloproteinases (MMPs) MMP-2 and MMP-9, and tissue inhibitors of metalloproteinases (TIMPs) TIMP- I and TIMP-2,as well as elastase content in wound fluid and angiogenesis,were evaluated, comparing results on day 0 and day 2 I.Time to ulcer healing, reduction in ulcer area, safety of treatment, patient-reported ulcer pain and comfort of the dressing regimen were evaluated as secondary outcomes. Patients received standard preventive measures, in line with the pressure ulcer prevention guidelines. RESULTS: Ten patients were included in the pilot; five were treated with the foam dressing (group A) and five patients received the collagen dressing, using the foam as a secondary dressing (group B).Wound fluid from group B displayed a significant positive effect on angiogenesis (p < 0.05) compared with group A. In the collagen and foam groupTIMP- I and -2 increased faster and levels were higher than in group A. Furthermore, MMP-2, MMP-9 (p < 0.04) and elastase in group B showed faster and greater decrease in levels, compared with group A, indicating a faster and superior reduction of inflammation. In both groups the ulcers started to heal, with a faster onset of healing for group B. CONCLUSION: The results of this pilot support published data on the use of collagen dressings compared with foam for stagnating wounds, shown in clinical studies. DECLARATION OF INTEREST: This study was supported with an educational grant by Lohmann & Rauscher GmbH.Apart from DrAbel, the sponsors had no role in the design or conduct of the study, in the collection, analysis and interpretation of the data, or in the preparation, review or approval of the manuscript. DrAbel gave input to the study design from a scientific perspective. None of the authors received administrative, technical or material support for the conduct of this study.The authors have no other relevant financial interests to declare.