[Registry Research Funding of the German Society of Plastic, Reconstructive and Aesthetic Surgery (DGPRÄC) and Research Funding Report 2021/2022]. / Register Forschungsförderung der Deutschen Gesellschaft für Plastische, Rekonstruktive und Ästhetische Chirurgie (DGPRÄC) und Forschungsförderungs-Bericht 2021/2022.

BACKGROUND: Research is an integral part of academic medicine. In plastic surgery, it sets the course for innovations in the specialty. The purpose of this study is to present the research performance of plastic surgeons in Germany for the period 2021/2022 and to compare it with previous periods. MATERIALS AND METHODS: The directors of plastic surgical academic institutions reported all requested/approved and rejected research applications to public, non-public and industrial funding organizations. Data was gathered within an established online database. In addition, the DFG´s public database GEPRIS was screened for plastic surgical research grants. Data was also collected regarding research infrastructure and organization at the participating centers. RESULTS: 105 applications were reported to 54 different funding agencies from 20 plastic surgery centers. 37 funding applications were submitted to the major public funding agencies DFG, BMBF, BMWi, BMG, BMVg, G-BA and EU. Of these, 59,5% (22/37) were DFG, 13,5% (5/37) each BMBF and EU, 5,4% (2/37) BMWi, and 2,7% (1/37) each BMG, BMVg, and G-BA applications. The average funding volume of these proposals was 401,515 euros. Approved DFG proposals were most frequently assigned to the review board 205-27 Orthopedics, Trauma Surgery, Reconstructive Surgery (n=10/16, 62,5%). Over time, the research registry shows an increase in the number of proposals in general and those granted. 70,0% (14/20) of participating sites had their own experimental research laboratory, while only 40,0% (8/20) had their own clinical trial center. CONCLUSION: The 2021/2022 Research Funding Report once again highlights the impressive research accomplishments of the plastic surgery community.

[Registry Research Funding of the German Society of Plastic, Reconstructive and Aesthetic Surgeons (DGPRÄC) and Research Funding Report 2019/2020]. / Register Forschungsförderung der Deutschen Gesellschaft der Plastischen, Rekonstruktiven und Ästhetischen Chirurgen (DGPRÄC) und Forschungsförderungsbericht 2019/2020.

BACKGROUND: Since 2015/16 the DGPRÄC collects, evaluates and publishes the research activities of academic sections, departments and clinics for plastic surgery at university hospitals in Germany, in order to raise the awareness of plastic surgical research performance. MATERIALS AND METHODS: The directors of plastic surgical academic institutions were contacted via the DGPRÄC and asked to report any requested/approved and rejected research applications to public, non-public and industrial funding organizations. Data was collected in our previously established online database: https://docs.google.com/forms/d/e/1FAIpQLSe6F5xmTyw-k7VKJx_2jkPA4LBXsA0sgBGMrC3rx_4bHj6uzQ/viewform?usp=sf_link. In addition, applications were identified via the DFG's public database GEPRIS. RESULTS: A total of 41 funding applications to the public funding institutes DFG, BMBF, BMWi, BMG and EU were identified. 75.6 % (31/41) of the applications had already been approved at the time of data collection, of which 77.4 % (24/31) were DFG, 9.7 % (3/31) were BMWi, 6.5 % (2/31) were EU and 3.2 % (1/31) were BMBF or BMG applications. The average funding amounted to 358 301 Euro. In 50.0 % (12/24) of the cases, the approved DFG proposals were assigned to the subject review board 205-27 Orthopedics, Trauma Surgery, Reconstructive Surgery. CONCLUSION: The continuous publication of plastic surgical research funding reports submitted by the convention of university plastic surgeons of the DGPRÄC portraits the excellent, collaborative research activity in the field of plastic surgery.

[Diagnostic accuracy of conventional X-ray imaging for assessment of trapeziometacarpal joint osteoarthritis]. / Genauigkeit der konventionellen Röntgendiagnostik bei der Beurteilung der Daumensattelgelenkarthrose.

BACKGROUND: Osteoarthritis of the trapeziometacarpal joint is a common and painful affliction that can be diagnosed using conventional X­ray imaging as well as arthroscopy and if necessary treated; however, the X­ray classification often does not sufficiently demonstrate the cartilage damage found in arthroscopy. OBJECTIVE: The aim of the study was to evaluate the diagnostic accuracy of conventional X­ray imaging compared to arthroscopy for osteoarthritis of the trapeziometacarpal joint. MATERIAL AND METHODS: The preoperative conventional X­ray images of 23 patients were presented to 10 experienced hand surgeons who were blinded to the arthroscopy results. Their ratings were compared to the results found with arthroscopy. RESULTS: Of the patients 11 were found to have grade 4 cartilage lesions according to the Outerbridge classification, 8 grade 3 lesions, 4 grade 2 lesions and no grade 1 lesions. Overall, 43% (95% confidence interval, CI 37-49%) of the cartilage lesions were diagnosed correctly using conventional X­rays. For grade 4 lesions 73% (95% CI 65-81%) of the surgeons made the correct diagnosis, in the case of grade 3 lesions 38% (95% CI 27-49%) and in grade 2 lesions 13% (95% CI 3-23%). CONCLUSION: This study presents an arthroscopy classification system that is specific for osteoarthritis of the trapeziometacarpal joint and provides an additional method of assessment if the X­ray grading of osteoarthritis according to Eaton and Littler is too unspecific. Arthroscopy can be used to safely differentiate the treatment-relevant stage and also includes treatment options.

[A critical analysis of perception of plastic surgery in Germany]. / Kritische Perzeptionsanalyse der plastischen Chirurgie in Deutschland.

BACKGROUND AND OBJECTIVES: Plastic surgery includes a broad range of activities; however, there are no studies available in Germany which evaluated the specific role plastic surgeons play in providing patient care. The aim of the project was thus to analyze the public and professional perception of plastic surgery in Germany and to what degree the range of activities is appropriately represented. MATERIAL AND METHODS: An anonymous survey inquiring about demographic data and specific knowledge regarding plastic surgery procedures was conducted in various regions in German. Furthermore, factors that potentially influence the state of knowledge and personal perception were collated. The questionnaire was distributed among healthcare professionals and patients in plastic surgery. The statistical evaluation was performed using SPSS software. RESULTS: A total of 2100 people participated in the nationwide survey. While classical aesthetic operations were mostly assigned to plastic surgery, there was no uniformity as to whether other indications, such as reconstructive interventions and hand surgery were assigned to this specialty or not. In this context various factors could be elucidated, such as the place of residence, education and age of the survey participants and the respective knowledge, which influence the perception. CONCLUSION: Plastic surgery in Germany classically consists of the four pillars of general reconstruction, hand surgery, burn management and aesthetic procedures; however, the results of this survey revealed that plastic surgery in Germany is predominantly understood as burn management and aesthetic surgery. As a multidisciplinary specialty, plastic surgery could apparently benefit from a more positive lobby and from a better portrayal of its scope in the media and general public.

[Registry Research Funding of the German Society of Plastic, Reconstructive and Aesthetic Surgeons (DGPRÄC) and Research Funding Report 2017/2018]. / Register Forschungsförderung der Deutschen Gesellschaft der Plastischen, Rekonstruktiven und Ästhetischen Chirurgen (DGPRÄC) und Forschungsförderungs-Bericht 2017/2018.

INTRODUCTION: This report serves to publicize the research of academic institutions for Plastic Surgery within our society DGPRÄC in 2017/2018 and sequels the funding report of 2015/2016. Applications to public, non-public, or industrial funding organizations were evaluated. At the same time, this paper analyses the number of approved DFG applications in Plastic, Thoracic and Vascular Surgery in the GEPRIS system. Contrary to these specialties, Plastic Surgery is not classified as an independent speciality in the subject structure of the DFG review board which results in a lack of transparency concerning Plastic Surgery research work. MATERIALS AND METHODS: Our previously established online database (https://docs.google.com/forms/d/1OaSnHyKTysawiI1ie7kfUxDf7nJP_RiTUJTsnb7Mq_E/edit) for reporting requested/ approved and rejected research applications to public, non-public and industrial funding organizations was continued and evaluated together with applications found in the DFG's public database GEPRIS. RESULTS: Compared to the previous year's report, the number of approved applications from public research organizations (DFG, BMBF, BMWi, EU) was increased from 23 to 27. We identified 19 approved DFG applications from Plastic Surgery, as compared to 9 and 8 applications by Thoracic and Vascular Surgery, respectively. SUMMARY: Taken together, this data emphasizes that our research is at least equal to that of other newly established surgical specialties within the framework of the DFG. Accordingly, we hope to provide further arguments for an adaptation of the DFG review boards subject structure to include Plastic Surgery as an independent specialty as it is for Vascular Surgery and Thoracic Surgery.

Increased levels of sodium chloride directly increase osteoclastic differentiation and resorption in mice and men.

To better understand the association between high salt intake and osteoporosis, we investigated the effect of sodium chloride (NaCl) on mice and human osteoclastogenesis. The results suggest a direct, activating role of NaCl supplementation on bone resorption. INTRODUCTION: High NaCl intake is associated with increased urinary calcium elimination and parathyroid hormone (PTH) secretion which in turn stimulates the release of calcium from the bone, resulting in increased bone resorption. However, while calciuria after NaCl loading could be shown repeatedly, several studies failed to reveal a significant increase in PTH in response to a high-sodium diet. Another possible explanation that we investigated here could be a direct effect of high-sodium concentration on bone resorption. METHODS: Mouse bone marrow macrophage and human peripheral blood mononuclear cells (PBMC) driven towards an osteoclastogenesis pathway were cultivated under culture conditions mimicking hypernatremia environments. RESULTS: In this study, a direct effect of increased NaCl concentrations on mouse osteoclast differentiation and function was observed. Surprisingly, in a human osteoclast culture system, significant increases in the number of tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts, calcitonin receptor (CTR)-positive osteoclasts, nuclear factor-activated T cells c1 (NFATc1) gene expression, and areal and volumetric resorptions were observed for increasing concentrations of NaCl. This suggests a direct, activating, cell-mediated effect of increased concentrations of NaCl on osteoclasts. CONCLUSIONS: The reported that enhanced bone resorption after high-sodium diets may not only be secondary to the urinary calcium loss but may also be a direct, cell-mediated effect on osteoclastic resorption. These findings allow us to suggest an explanation for the clinical findings independent of a PTH-mediated regulation.

[Locoregional solutions for groin defects : Coverage after vascular surgery]. / Lokoregionale Lösungen bei Leistendefekten : Deckung nach gefäßchirurgischen Eingriffen.

INTRODUCTION: Vascular surgery through a groin incision may be associated with severe wound healing disorders in this sensitive area. There are many options to reconstruct the defect surgically. The choice of surgical reconstruction depends mainly on the individual status of vasculature, which is most often compromised in these patients. There are random pattern flaps, as well as perforator, pedicled flaps or microvascular flaps to choose from. AIM: We give an overview of plastic surgical solutions for groin defects, with a special focus on complex wounds after vascular surgical complications. We discuss advantages and disadvantages of different flaps with two case reports and also show alternatives. PATIENTS AND METHODS: We demonstrate in two cases how the reconstruction of the groin defect was planned, taking into account the vascular status, and why we chose an innovative and seldom-used option in each case. RESULTS: The selected flaps, a pedicled fasciocutaneous ALT propeller flap and a perforator-based, pedicled abdominal advancement flap reconstructed the defects successfully. DISCUSSION: The surgical therapy for the reconstruction of groin defects should be chosen according to the individual vascular status to ensure safe and reliable blood supply. To guarantee the best possible reconstruction and avoid postoperative healing disorders and infections, less common flaps should also be considered.

[Overview and Introduction of a Treatment Concept for Postoperative Care and Mobilisation After Free Flap Transplantation in the Lower Extremity]. / Überblick und Vorstellung eines Behandlungskonzeptes zur postoperativen Therapie und Mobilisation nach freier Lappenplastik an der unteren Extremität.

Introduction: Free flap transplants for soft tissue reconstruction in the lower extremity are associated with a higher rate of complications compared with other areas. Mobilisation and the resulting hydrostatic pressure put strain on the flaps. In general, these effects are countered by slowly increasing hydrostatic pressure with the leg being compressed by elastic bandages. These postoperative regimes are also called dangling procedures or "flap training", but are not scientifically validated and therefore there is no consensus or guideline leading to a standard treatment regime. The goal of our study was to present an overview of currently performed regimes. Material and Methods: We conducted an email survey by sending a questionnaire to departments for plastic and reconstructive surgery in Germany, Austria and Switzerland, which perform free flap transplantations in the lower extremity. The questionnaire ascertained the starting point and the frequency of the dangling procedures, the introduction of weight-bearing on the operated extremity and the incidence of complications occurring during mobilisation. Results: We included 32 departments and compared them by the number of free flap transplantations performed per year. We found a wide variation between the postoperative treatment regimes. In most departments, flap training is started between the 3rd and 7th day after surgery and lasts between 5 and 15 min. The intervals with which flap training intensity is increased are inhomogeneous as well. The time until full weight-bearing is exerted on the operated extremity ranges from day 5 to week 3 postoperatively. Complications due to flap training were reported by one third of the participating departments. Conclusion: Elastic compression and patient mobilisation after free flap procedures in the lower extremity are considered to be very important in reducing complications and in protecting the flap from edema and volume overload. This article demonstrates that there is a wide variety in flap training regimes. It aims to help readers evaluate their own regimes and provides guidance for an individualised patient-oriented regime.

[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.

[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.

Anatomical and histomorphometric observations on the transfer of the anterior interosseous nerve to the deep branch of the ulnar nerve.

This study focuses on the anatomical and histomorphometric features of the transfer of the anterior interosseous nerve to the deep motor branch of the ulnar nerve. The transfer was carried out in 15 cadaver specimens and is described using relevant anatomical landmarks. Nerve samples of donor and target nerves were histomorphometrically analysed and compared. The superficial and the deep ulnar branches had to be separated from each other for a length of 67 mm (SD 12; range 50-85) to reach the site of coaptation. We identified a suitable site for coaptation lying proximal to the pronator quadratus muscle, 202 mm (SD 15; range 185-230) distal to the medial epicondyle of the humerus. The features of the anterior interosseous nerve included a smaller nerve diameter, smaller cross-sectional area of fascicles, fewer fascicles and axons, but a similar axon density. The histomorphometric inferiority of the anterior interosseous nerve raises a question about whether it should be transferred only to selected parts of the deep motor branch of the ulnar nerve.Level III.

[Primary adaptive vs. secondary wound closure in hand infections - differences and benefits]. / Primär adaptierende vs. sekundäre Wundverschlüsse bei Infektionen der Hand - Unterschiede und Vorteile.

BACKGROUND: Hand infections are common surgical emergencies. There are still controversial opinions regarding the ideal timing of wound closure after radical débridement of the infection. The aim of this retrospective study was to compare the outcome of primary adaptive and secondary wound closures after operative débridement in patients with hand infections. METHODS: We retrospectively analysed all infections of the hand treated operatively in our hospital in the years 2011 and 2012 with a follow-up of at least 6 months. We included 16 patients with primary adaptive wound closure (PWC) and 12 patients with secondary wound closure (SWC) in this study. The evaluated parameters were the need for re-operations, the length of hospital stay, the overall satisfaction with the treatment, the characteristics of the scar and the mobility of the hand. RESULTS: No patient had to be re-operated after PWC or SWC, respectively. Patients in the PWC group were kept significantly shorter as inpatients in comparison to patients in the SWC group (3.0 days vs. 5.1 days; p=0.048). Overall patient satisfaction with the treatment and the scar was comparable for both groups, as was the re-establishment of the mobility of the treated hand to preoperative levels. CONCLUSION: This study shows that wounds after radical débridement for infection of the hand can be closed primarily adaptive without disadvantages for the patient. The length of hospitalisation is significantly shorter if the wound is closed primarily adaptive, a fact that is important for patient comfort and the socio-economic system. Both, primary adaptive and secondary wound closures generally have good outcomes with possible advantages for primary adaptive wound closures concerning the characteristics of the scar.

[Training in aesthetic surgery at a university clinic - the "Munich model"]. / Weiterbildung in der ästhetischen Chirurgie an einer Universitätsklinik - Das "Münchner Modell"

BACKGROUND: Aesthetic surgery is regarded as one of the 4 pillars of plastic surgery. To assure safety in this field of surgery, a structured and well guided surgical training is indispensable. However, during the specialist training for plastic and aesthetic surgery, plastic aesthetic interventions are often carried out in low numbers only. Objective of the present study was the development, implementation and evaluation of a new training concept in aesthetic surgery. PATIENTS: Over a period of 2 years, 304 aesthetic operations were performed in the fields of body contouring, breast surgery and facial surgery as an "educational surgery". Educational surgeries were performed by resident surgeons under the guidance of experienced specialists and under favourable financial conditions. As indicator for safety of the interventions, the incidence of complications was recorded and assessed. RESULTS: Out of a total of 304 operations included in the study 47.7% were performed as an educational surgery. In the fields of body contouring and breast surgery, the majority of interventions (51.3% and, respectively, 53%) were carried out as educational surgeries. In aesthetic surgeries of the face only 28.4% were educational surgeries. In 4.9% of all cases complications occurred. The incidences of complications were approximately the same in the educational surgeries (5.5%) and in the surgeries carried out by experienced specialists (4.4%), showing no significant difference. CONCLUSION: The presented training concept aims at ensuring high quality in patient care by structure and quality of surgical training. Our data give evidence that a structured training of residents in the field of aesthetic surgery is possible without loss in quality. We expect that -sufficient surgical education and the associated quality will consequently contribute to keep aesthetic surgeries a domain of plastic surgery and to prevent these procedures from being taken over by other surgical disciplines.

[Return of sensitivity after digital nerve reconstruction in children: how does age affect outcome?]. / Sensibilitätsrückkehr nach kindlichen Nervenverlet-zungen der Hand - welche Rolle spielt das Patientenalter?

BACKGROUND: The regenerative capacity after nerve reconstruction in children is believed to be superior compared to that in adults. However, the available data on this topic are limited. The aim of this work is to improve the age-dependent assessment of the prognosis after surgical treatment of peripheral nerve injuries of the hand. PATIENTS AND METHODS: 44 of 147 children with complete transections of proper and common digital nerves who were treated from 2000 to 2009 and who were currently 6 years or older, could be included for follow-up (mean time, 7.5 years). In total there were 60 nerve injuries, of which 56 were directly coaptated, 4 needed grafting. Sensitivity of the fingertips was assessed using the 2-point discrimination (2PD) test and the Semmes-Weinstein monofilament test. We also recorded hypersensitivity, sensitivity to cold, and paresthesia. To account for inter-individual differences in normal 2PD, the difference of the 2PD to the uninjured contralateral side was calculated as delta-2PD. The age at the time of the injury, divided into groups of 0-5, 6-10 and 11-15 years was correlated with the clinical outcome (2PD, monofilamenttest). Taking into account the results classified by age presented by Lohmeyer et al. and Mailänder et al., we assessed the correlation between age at injury (0-85 years) and clinical outcome. RESULTS: After 52 of the 56 direct nerve coaptations (93%) normal sensitivity was found with a 2PD<6 mm, 4 times the 2PD was 6 mm. Following nerve grafting a static 2PD of 6-7 mm was measured. Disturbing paresthesia, sensitivity to cold or hypersensitivity were not reported by any patient. The 2PD of the fingers of the opposite uninjured side showed great inter-individual differences. Patient's age and 2PD significantly correlated with significantly poorer results already in the second decade of life. CONCLUSION: In relation to adults, children have an excellent prognosis after nerve reconstruction. The high inter-individual differences in regular sensitivity, depending on age, co-morbi-dities, etc., suggest putting the results of the injured and uninjured sides into relation. Estimation of the Δs2PD may solve this -problem.

[Autologous fat grafts and supportive enrichment with adipose tissue stromal cells]. / Autologe Fetttransplantation in der Brustchirurgie - Klinische und Experimentelle Konzepte: vom Lipofilling bis zum Fettgewebe Tissue Engineering.

Liposuction is a most common surgical procedure in aesthetic surgery that aims at the local fat reduction. The obtained adipose tissue is currently used as a biocompatible filler. Autologous fat transplantation, also known as lipofilling, has become an attractive treatment method in the field of aesthetic facial surgery and scar tissue reconstruction. Lipofilling may also offer an alternative method to prosthetic breast surgery. Nevertheless, postoperative fat tissue resorption is still a limitiation to lipofilling in breast reconstruction leading to multiple revisions in order to reach the requested clinical outcome. The therapeutic effect of autologous fat grafts does not solely lie in its role as a filler material, but also in its wound healing and angiogenetic properties. The latter is not attributed to the mature adipocytes, but rather to the undifferentiated adipose derived stromal cells (ASC). Thus enrichment of the fat graft with autologous ASC, known as cell-assisted lipotransfer (CAL) may lead to further optimisation of lipofilling concerning fat graft survival. Still aiming to establish the application of autologous fat grafts and ASC in breast reconstruction, there is a necessity for systematic analyses in order to resolve questions regarding the operational technique and qualitative aspects of the ASC manufacturing in accordance with pharmaceutical guidelines and regulations in Germany. Besides, some open questions need to be addressed regarding the ASC differentiation potential in vivo.

[Erythropoietin in plastic surgery]. / Erythropoetin in der Plastischen Chirurgie.

EPO is an autologous hormone, which is known to regulate erythropoiesis. For 30 years it has been used for the therapy of diverse forms of anaemia, such as renal anaemia, tumour-related anaemias, etc. Meanwhile, a multitude of scientific publications were able to demonstrate its pro-regenerative effects after trauma. These include short-term effects such as the inhibition of the "primary injury response" or apoptosis, and mid- and long-term effects for example the stimulation of stem cell recruitment, growth factor production, angiogenesis and re-epithelialisation. Known adverse reactions are increases of thromboembolic events and blood pressure, as well as a higher mortality in patients with tumour anaemias treated with EPO. Scientific investigations of EPO in the field of plastic surgery included: free and local flaps, nerve regeneration, wound healing enhancement after dermal thermal injuries and in chronic wounds.Acute evidence for the clinical use of EPO in the field of plastic surgery is still not satisfactory, due to the insufficient number of Good Clinical Practice (GCP)-conform clinical trials. Thus, the initiation of more scientifically sound trials is indicated.

Cell-free carrier system for localized delivery of peripheral blood cell-derived engineered factor signaling: towards development of a one-step device for autologous angiogenic therapy.

Spatiotemporally-controlled delivery of hypoxia-induced angiogenic factor mixtures has been identified by this group as a promising strategy for overcoming the limited ability of chronically ischemic tissues to generate adaptive angiogenesis. We previously developed an implantable, as well as an injectable system for delivering fibroblast-produced factors in vivo. Here, we identify peripheral blood cells (PBCs) as the ideal factor-providing candidates, due to their autologous nature, ease of harvest and ample supply, and investigate wound-simulating biochemical and biophysical environmental parameters that can be controlled to optimize PBC angiogenic activity. It was found that hypoxia (3% O2) significantly affected the expression of a range of angiogenesis-related factors including VEGF, angiogenin and thrombospondin-1, relative to the normoxic baseline. While all three factors underwent down-regulation over time under hypoxia, there was significant variation in the temporal profile of their expression. VEGF expression was also found to be dependent on cell-scaffold material composition, with fibrin stimulating production the most, followed by collagen and polystyrene. Cell-scaffold matrix stiffness was an additional important factor, as shown by higher VEGF protein levels when PBCs were cultured on stiff vs. compliant collagen hydrogel scaffolds. Engineered PBC-derived factor mixtures could be harvested within cell-free gel and microsphere carriers. The angiogenic effectiveness of factor-loaded carriers could be demonstrated by the ability of their releasates to induce endothelial cell tubule formation and directional migration in in vitro Matrigel assays, and microvessel sprouting in the aortic ring assay. To aid the clinical translation of this approach, we propose a device design that integrates this system, and enables one-step harvesting and delivering of angiogenic factor protein mixtures from autologous peripheral blood. This will facilitate the controlled release of these factors both at the bed-side, as an angiogenic therapy in wounds and peripheral ischemic tissue, as well as pre-, intra- and post-operatively as angiogenic support for central ischemic tissue, grafts, flaps and tissue engineered implants.