Microvascular Muscle vs. Fascio-Cutaneous Free Flaps for Reconstruction of Plantar Load-Bearing Foot Defects-An International Survey.

Background: The reconstruction of plantar load-bearing foot defects faces many plastic surgeons with a major challenge. The optimal patient- and defect-oriented reconstructive strategy must be selected. Methods: To analyze the current trends and recommendations in reconstruction of plantar load-bearing foot defects, we conducted an international survey among plastic surgeons querying them about their recommendations and experiences. Results: The survey revealed that the most common strategies for reconstruction of the foot sole are locoregional and microvascular free flaps, emphasizing the relevance of plastic surgery. Among microvascular free flaps, muscle and fascio-cutaneous free flaps are by far the most frequently used. The target qualities of the reconstructed tissue to be considered are manifold, with adherence being the most frequently mentioned. We observed a noteworthy correlation between the utilization of muscle flaps and a preference for adherence. In addition, we identified a substantial correlation between the usage of fascio-cutaneous free flaps and further target qualities, such as good skin quality and sensitivity. Conclusions: Our findings provide insights into the clinical reality and highlight important aspects that must be considered in reconstruction of the weight-bearing areas of the foot providing support in the selection of the appropriate therapy.

[Perioperative Use of Antibiotics as Infection Prophylaxis in Elective Wrist Arthroscopy: A Nationwide Survey]. / Einsatz von Antibiotikum zur perioperativen Infektprophylaxe in der elektiven Handgelenksarthroskopie: Eine deutschlandweite Befragung.

BACKGROUND: Wrist arthroscopy is a standard procedure in hand surgery for the diagnosis and treatment of wrist conditions. While perioperative antibiotic prophylaxis (PAP) is not generally recommended for elective hand surgery, there is no official standard for elective wrist arthroscopy. This study aimed to determine the actual clinical use of PAP in elective wrist arthroscopy in Germany and relate it to the structural conditions of clinics performing this procedure. MATERIAL AND METHODS: We conducted a systematic search of all facilities in Germany offering wrist arthroscopy. Among these, we performed an online survey using the SoSci Survey online tool via email. RESULTS: PAP is more frequently administered in cases involving simultaneous bone procedures. Cephalosporins are the most commonly used antibiotics in cases of PAP administration. Hospitals administer PAP more frequently than outpatient settings, with most surveyed institutions following facility-specific internal standards for antibiotic administration. The number of arthroscopies performed in the surveyed centres does not influence antibiotic administration. CONCLUSIONS: The use of PAP in wrist arthroscopies in Germany is inconsistent. The increased use in arthroscopies with bone involvement corresponds to AWMF guidelines, but a general recommendation for wrist arthroscopies, including soft tissue arthroscopies, is necessary to provide physicians with medical and legal certainty.

Diagnostic power of ChatGPT 4 in distal radius fracture detection through wrist radiographs.

Distal radius fractures rank among the most prevalent fractures in humans, necessitating accurate radiological imaging and interpretation for optimal diagnosis and treatment. In addition to human radiologists, artificial intelligence systems are increasingly employed for radiological assessments. Since 2023, ChatGPT 4 has offered image analysis capabilities, which can also be used for the analysis of wrist radiographs. This study evaluates the diagnostic power of ChatGPT 4 in identifying distal radius fractures, comparing it with a board-certified radiologist, a hand surgery resident, a medical student, and the well-established AI Gleamer BoneView™. Results demonstrate ChatGPT 4's good diagnostic accuracy (sensitivity 0.88, specificity 0.98, diagnostic power (AUC) 0.93), surpassing the medical student (sensitivity 0.98, specificity 0.72, diagnostic power (AUC) 0.85; p = 0.04) significantly. Nevertheless, the diagnostic power of ChatGPT 4 lags behind the hand surgery resident (sensitivity 0.99, specificity 0.98, diagnostic power (AUC) 0.985; p = 0.014) and Gleamer BoneView™(sensitivity 1.00, specificity 0.98, diagnostic power (AUC) 0.99; p = 0.006). This study highlights the utility and potential applications of artificial intelligence in modern medicine, emphasizing ChatGPT 4 as a valuable tool for enhancing diagnostic capabilities in the field of medical imaging.

[Coverage of complex pararectal pelvic defects: role of the free myocutaneous musculus vastus lateralis flap]. / Deckung komplexer pararektaler Beckendefekte: Rolle der freien myokutanen Musculus vastus lateralis Lappenplastik.

BACKGROUND: In the event of an advanced rectal carcinoma, an evisceration with rectal amputation may become necessary. The resulting defects, due to their extent, depth, or local tissue damage from previous surgeries and radiation, can in many cases only be closed through free microvascular tissue transfer. In this case series, we demonstrate the successful combination of a musculocutaneous musculus vastus lateralis flap (MVL) with a direct connection to the superior gluteal artery. MATERIALS AND METHODS: Over a 47-month period, we retrospectively examined 11 cases of patients with dorsal pelvic defects after evisceration and rectal amputation that could not be closed using local or regional means. In cases of extensive defects with deep pararectal wound cavities, all these patients underwent defect coverage through a free myocutaneous MVL flap with a direct vascular anastomosis to the superior gluteal vessels. RESULTS: The mean defect size was 290.0 cm² (SD: 131.2; range: 200-600 cm²). The mean defect depth was 10.5 cm, necessitating MVL flap reconstruction with an average size of 336.3 cm². Three operative revisions were required due to postoperative bleeding. There were no arterial or venous thromboses, and no flap loss occurred. Only one necrosis of a distal flap tip was observed, which could be corrected secondarily by direct suturing. The case-mix evaluation yielded an average value of 24.251 (SD: 21.699; range: 7.036-65.748) points, emphasizing the complexity of the cases. CONCLUSIONS: Our results indicate that a free microvascular MVL flap is a viable therapeutic option for pararectal defects that cannot be closed by local or regional methods. The superior gluteal artery proves to be a safe and sufficient vascular connection. In combination, even extensive defects can be successfully closed.

Postoperative Benefits of Soft Tissue Wrist Arthroscopy: Retro- and Prospective Analyses of Outcome Measures.

Background: Elective soft-tissue-only wrist arthroscopy is a standard procedure in hand surgery for the diagnosis and treatment of wrist pain. A number of pathologies can be treated arthroscopically, with the aim of pain reduction and improved wrist mobility. A postinterventional evaluation of the treatment using objective and patient-reported outcome measures (PROMs) allows for an evidence-based statement about the benefits of soft-tissue-only wrist arthroscopy. Methods: A dual-center study combining retro- and prospective clinical analyses of patient outcomes after soft-tissue-only wrist arthroscopies was performed. The data were collected at two hospitals with departments specializing in hand surgery. The outcome was measured by assessing the range of motion of the wrist and its manual strength, as well as PROMs, including Disabilities of the Arm, Shoulder and Hand (DASH) scores. Results: A total of 154 soft interventions met the study criteria and could be included. Seven months after the elective soft-tissue-only wrist arthroscopies, mobility improved significantly for active extension and flexion, as well as the ulnar and radial abduction of the wrist. The grip strength also improved significantly, by an average of 6 kg, during this period. The DASH score improved significantly, from 35 points to 14 points. Additionally, wrist pain at rest was reduced significantly. Conclusions: After elective soft-tissue-only wrist arthroscopy, patients showed an overall functional improvement in their wrist, with a significant reduction in pain and improvement of mobility and grip strength. This study emphasizes the importance of wrist arthroscopy as a successful treatment option for soft tissue pathologies of the wrist.

[Robotic-assisted harvesting of a latissimus dorsi muscle flap: a case report]. / Roboter-assistierte Hebung der M. latissimus dorsi ­ Lappenplastik: Ein Fallbericht.

Having established itself in various other areas of surgery as well as in urology, robotics is increasingly gaining importance in plastic surgery. The case presented in this manuscript describes the first published robotic-assisted harvesting of a latissimus dorsi muscle free flap in the German-speaking world. The aim is to increase the knowledge of robotics in plastic surgery and to support the introduction of robotic-assisted plastic surgery in Germany.

ESPRAS Survey: National and European Societies for Plastic Surgeons.

BACKGROUND: The European Society of Plastic, Reconstructive and Aesthetic Surgery (ESPRAS) comprises 40 national societies across Europe. In addition to ESPRAS, there are 8 different European Plastic Surgery societies representing Plastic Surgeons in Europe. The 4th European Leadership Forum (ELF) of ESPRAS, held under the motto "Stronger together in Europe" in Munich in 2023, aimed to collect and disseminate information regarding the national member societies of ESPRAS and European societies for Plastic Surgeons. The purpose was to identify synergies and redundancies and promote improved cooperation and exchange to enhance coordinated decision-making at the European level. MATERIAL AND METHODS: An online survey was conducted regarding the organisational structures, objectives and challenges of national and European societies for Plastic Surgeons in Europe. This survey was distributed to official representatives (Presidents, Vice Presidents and General Secretaries) and delegates of national and European societies at the ELF meeting. Missing information was completed using data obtained from the official websites of the respective European societies. Preliminary results were discussed during the 4th ELF meeting in Munich in March 2023. RESULTS: The ESPRAS survey included 22 national and 9 European Plastic Surgery societies representing more than 7000 Plastic Surgeons in Europe. Most national societies consist of less than 500 full members (median 182 members (interquartile range (IQR) 54-400); n=22). European societies, which covered the full spectrum or subspecialities, differed in membership types and congress cycles, with some requiring applications by individuals and others including national societies. The main purposes of the societies include research, representation against other disciplines, specialisation and education as well as more individual goals like patient care and policy regulation. CONCLUSION: This ESPRAS survey offers key insights into the structures, requirements and challenges of national and European societies for Plastic Surgeons, highlighting the relevance of ongoing close exchange between the societies to foster professional advancement and reduce redundancies. Future efforts of the ELF will continue to further explore strategies for enhancing collaboration and harmonisation within the European Plastic Surgery landscape.

Abdominoplasty in a Patient With Type 3 von Willebrand Disease: A Case Report.

ABSTRACT: von Willebrand disease (vWD) is an inherited bleeding disorder that is characterized by a quantitative or qualitative deficiency of the von Willebrand factor (vWF). Type 3 is the most severe form of vWD with a near-complete absence of vWF and a significantly increased risk of excessive bleeding and hematoma during a surgical procedure. To date, no data on surgical and hemostatic management of a type 3 vWD patient undergoing body-contouring surgery has been published. We report the case of a 47-year-old woman with type 3 vWD requiring medically indicated abdominoplasty after massive weight loss due to bariatric surgery. The case was successfully managed with individualized bodyweight-adapted substitution of recombinant vWF vonicog alfa and tranexamic acid under close monitoring of vWF and factor VIII activity. For further risk stratification, we propose the multidisciplinary treatment of patients with severe vWF undergoing elective plastic surgery in specialized centers providing around-the-clock laboratory testing and access to a blood bank. In addition, strict hemostasis during surgery and early postoperative mobilization with fitted compression garments are recommended to further reduce the risk of bleeding and thromboembolic complications.

The Influence of Scar Patterns After Reduction Mammoplasty on Eye Movement and Gaze Pattern: An Eye-Tracking Investigation.

BACKGROUND: Given that scars are acknowledged as the primary cause of postoperative dissatisfaction following reduction mammoplasty, it is imperative to comprehend the patient's visual perception of different scar patterns in order to enhance patient satisfaction. To achieve this, eye-tracking technology provides an unbiased method of evaluating how observers assess breast scars. METHODS: 58 participants (32 females and 26 males) between the ages of 19 and 82 years (mean age of 29.47 ± 10.98 years) were shown 18 color photographs, taken at 3 viewing angles (right 45° oblique, frontal and frontal view with arms raised), from 6 patients undergone reduction mammoplasty with the inverted T-scar technique (3 patients) or no-vertical-scar technique (3 patients). The images were presented to every participant for a fixed duration of 5 s each. Eye-tracking device was used to collect and analyze the gaze data of viewers. RESULTS: The nipple-areola complex (NAC) and the periareolar scar captured observers' gaze faster, had longer duration and more count of eye fixation than all other parts of breast scars, regardless of the viewing angle and scar pattern. Moreover, the scar region in the inverted T-scar pattern received greater and faster visual attraction of observer's gaze than the no-vertical-scar pattern. CONCLUSION: The NAC and the periareolar scar seem to be perceived as the most important regions for breast aesthetics. The findings can be helpful to assist plastic surgeons in determining the most appropriate technique for reduction mammoplasty, meanwhile underlining the importance of a fine periareolar scar and symmetric NAC for excellent aesthetic outcomes. This is to our best knowledge the first study using eye-tracking technology in evaluating reduction mammoplasty outcomes. This study explored the influence of different scar patterns after reduction mammoplasty on eye movements and gaze patterns among observers. The study have validated the significance of the NAC and the periareolar scar for breast aesthetics and revealed that the scar region in the inverted T-scar pattern may be judged less visually attractive than the no-vertical-scar pattern. LEVEL OF EVIDENCE V: 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 .

[German Translation and Validation of the Patient-Oriented Questionnaire "Thumb Disability Examination" (TDX) for Specific Diagnosis and Follow-Up of Thumb Carpometacarpal Joint Osteoarthritis]. / Deutsche Übersetzung und Validierung des patienten-orientierten Fragebogens "Thumb Disability Examination" (TDX) zur spezifischen Diagnostik und Verlaufskontrolle bei Rhizarthrose.

BACKGROUND: Patient-reported outcome measures (PROMs) are becoming increasingly important in today's patient care. Unfortunately, the most common PROMs in hand surgery are very time-consuming and usually do not cover the actual, diagnosis-specific complaints of the patients. For diagnosis and follow-up of thumb carpometacarpal joint osteoarthritis, Noback et al. developed and validated the Thumb Disability Examination (TDX) questionnaire. This 20-item questionnaire specifically assesses daily living limitations and pain as well as patient-reported satisfaction of thumb function. The aim of this study is to validate the German translation of the TDX, the Thumb Disability Examination - German (TDX-G), and to compare it with the German-language versions of the MHQ and qDASH, which are currently used as gold standard. MATERIAL UND METHODS: Translation and back-translation were performed in accordance with accepted guidelines. For statistical validation of the TDX-G, 30 consecutive patients with thumb carpometacarpal joint osteoarthritis were interviewed under standardised conditions. Internal consistency was calculated using Cronbach's alpha. Test-retest reliability was determined in 10 patients who completed the TDX-G twice at an interval of 2 weeks. The validity of the TDX-G was determined by calculating the correlation coefficients of the TDX-G with the MHQ and qDASH, subjective pain sensation (NRS), and hand strength levels (coarse and pinch strength). In addition, the time to collect each questionnaire was compared. RESULTS: The TDX-G has high internal consistency (Cronbach's alpha 0.932) and test-retest reliability (intraclass correlation coefficient 0.963 [0.850-0.991]). There is a significant correlation between TDX-G and MHQ (- 0.782; p<0.001) and qDASH (0.833; p<0.001). All questionnaires correlate significantly with pain on exertion and pinch force, with the TDX-G having the highest correlation in each case. Significantly less time is needed to record the TDX-G (110±28 s) than to record the MHQ (413±98 s). CONCLUSION: The TDX-G is a reliable tool for diagnosing and monitoring the progression of thumb carpometacarpal joint osteoarthritis. It can be used in both patient care and clinical research and accurately mirrors the symptoms.

[Goal-setting in Plastic Surgery using the SMART principle]. / Operative Ausbildungsziele in der Plastischen und Ästhetischen Chirurgie einfach "SMART".

INTRODUCTION: The process of continuous acquisition of surgical expertise is a key element in registrar training. The principle of active, self-directed learning, which is regularly applied in medical school, can also be used to gain surgical expertise in registrar training. METHODS: Surgical training can be compared to acquiring expertise in music or sport, where both intellectual and manual capabilities are required. Specific training principles, including analysis, goal setting, practice and reflection on the process, are commonly encountered in these fields. Smart goal setting is preferred in order to ensure compliance and a successful strategy. This can also be used in plastic surgery training. APPLICATION: Surgical principles as well as partial or complete surgical procedures can be practiced using the smart principle. The fragmentation of a larger task into smaller units allows rapid acquisition of surgical expertise without impeding patient safety. DISCUSSION: Surgical training today happens in a setting caught between economic and medicolegal challenges. The reduction of case load requires simulation practice as well as self-directed learning - which has been shown to improve outcomes. The smart principle allows distinct goal setting which can improve compliance of the student and increase success. As this form of learning is not intuitive to all individuals, supervisors and mentor can support trainees in the acquisition of surgical expertise using this principle.

The minimum required overlap length for tendon transfer A biomechanical study on human tendons.

In tendon transfer surgeries sufficient stability of the tenorrhaphy is essential. In addition to the choice of a suitable technique, adequate overlap of donor and recipient tendons must be ensured. The aim of this study was to investigate the tensile strength with regard to tendon overlap of a recently published tenorrhaphy, termed Woven-Fridén (WF) tenorrhaphy, which displayed higher tensile strength and lower bulk when compared to the established Pulvertaft technique. For this purpose, WF tenorrhaphies with 1.5 cm, 2 cm, and 3 cm tendon overlap were performed and subsequently tested for different biomechanical properties by tensile testing. Among others, the parameters of ultimate load and stiffness were collected. Native tendons served as controls. A formula was derived to quantify the relation between tendon overlap and ultimate load. We observed that sufficient tensile strength (mean ultimate load of 217 N) is already given with a 2 cm tendon overlap. In addition, with more than 3 cm overlap length only little additional tensile strength is to be expected as the calculated ultimate load of 4 cm overlap (397 N) is approaching the plateau of the maximal ultimate load of 435 N (native tendons).

[Current Trends in Flexor Tendon Surgery: Results of a National Online Survey]. / Aktuelle Trends in der Beugesehnenchirurgie ­ Ergebnisse einer nationalen Online-Umfrage.

Within the last 50 years, there has been a change in trend in flexor tendon surgery. After the introduction of the 2-strand technique, the 4-strand technique was propagated in the 1990s. In order to obtain a status quo of which technique is used in Germany and if the gold standard of the 4-strand suture has changed in favour of a 6-strand suture, we conducted an online survey among members of the DGH ("Deutsche Gesellschaft für Handchirurgie", German Society for Hand Surgery) on the suture technique of flexor tendon injuries zone 2. MATERIAL AND METHODS: An online survey was conducted and sent out by email to all DGH members. The questionnaire included 7 questions. Participants accessed the survey via a link. RESULTS: 155 hand surgeons from Germany participated in the survey. All of them answered the questionnaire in full and all questionnaires were included in the evaluation. The main question of how many strands are currently used for core suturing was answered as follows: 21% (n=32) of the 155 participants (TN) stated that they use a 2-strand suture, 53% used (n=82) a 4-strand suture and 10% used a 6-strand suture. Regarding techniques, 81 TN used the Kirchmayr-Kessler technique or a modification of it, 9 TN used the M-Tang technique, and 15 TN indicated "other technique". The question about the application of an epitendinous suture was overwhelmingly answered with "yes". Here, 98.2% agreed. Only with regard to the suture material, different opinions were found. 68% (n=106) use an absorbable monofilament suture (such as PDS). Just under a quarter (23%, n=36) use a non-absorbable monofilament suture (such as Prolene). CONCLUSION: Flexor tendon surgery has changed considerably due to intensive advances in research during the last decades. It was interesting to note in our survey that German hand surgeons have adapted their suture technique within the last years based on the results of the literature. Our results clearly show that convincing scientific data has an influence on the choice of surgical technique and that discussions about new techniques, e. g. in the context of annual meetings, may well stimulate the auditorium to rethink.

[Breast implant-associated squamous cell carcinoma: a systematic literature review]. / Brustimplantat assoziiertes Plattenepithelkarzinom (BIA-SCC) ­ eine systematische Literaturübersicht.

BACKGROUND: Breast implant-associated squamous cell carcinoma (BIA-SCC) is being discussed as a distinct malignant tumour entity originating from the implant capsule. The FDA and the ASPS published a safety communication on BIA-SCC in 2022, with a first case report of BIA-SCC having been published in the 1990s. This manuscript summarises the current scientific data on this rare tumour entity. MATERIAL AND METHODS: This systematic literature review from two independent databases includes all publications of cases with histopathologically confirmed BIA-SCC. Data extraction included study design, demographic data, implant information and details regarding diagnosis and treatment. RESULTS: Nineteen cases of BIA-SCC with a mean age of 57±10 years were reported in 16 publications. In most cases, the indication was aesthetic augmentation (n=13). Both silicone (n=11) and saline (n=7) implants with different surfaces (smooth n=3, textured n=3, polyurethane n=1) were used. Symptoms such as unilateral swelling (n=18), pain (n=14) and erythema (n=5) occurred on an average of 23±9 years after implantation. Imaging showed fluid collection (n=8) or a tumour mass (n=4) around the breast implant. The most common surgical treatment was explantation with capsulectomy. Metastasis was described in 6 cases. CONCLUSIONS: BIA-SCC is a malignant tumour entity associated with breast implant capsules. Based on current low-quality data (level of evidence class V), no definitive conclusion regarding correlation and causality of SCC in patients with breast implants can be drawn. There is an urgent need for national and international breast implant and breast cancer registries to obtain valid data on the incidence, pathogenesis and clinical presentation of rare tumour entities.

[Relevance of Early Structured Diagnosis to Successful Nerve Reconstruction: A Case Report of an Alpine Professional Skier with an Axillary Nerve Injury]. / Relevanz früher strukturierter Diagnostik zur erfolgreichen Nervenrekonstruktion: Ein Fallbericht bei Nervus axillaris ­ Verletzung einer alpinen Profi-Skisportlerin.

Among high-speed sports, an increased number of high-speed injuries have been observed in alpine downhill racing. We report the case of a young professional ski racer who sustained a shoulder dislocation with an avulsion of the axillary nerve during a World Cup race. After initial treatment was provided for the shoulder dislocation, the patient was left with abduction weakness and a sensory deficit in the region of the deltoid muscle. She underwent electrophysiological and clinical examinations and visited our centre with delay. We immediately performed surgical treatment with a nerve transfer and nerve transplantation. After only 11 months following her fall, she was able to resume her training program. This case report shows the importance of early diagnostic investigation, a visit to a centre of plastic surgery and the good outcome after surgical treatment in patients with peripheral nerve injuries.

The use of commercial fibrin glue in dermal replacement material reduces angiogenic and lymphangiogenic gene and protein expression in vitro.

BACKGROUND: Commercial fibrin glue is increasingly finding its way into clinical practice in surgeries to seal anastomosis, and initiate hemostasis or tissue repair. Human biological glue is also being discussed as a possible cell carrier. To date, there are only a few studies addressing the effects of fibrin glue on the cell-molecular level. This study examines the effects of fibrin glue on angiogenesis and lymphangiogenesis, as well as adipose-derived stem cells (ASCs) with a focus on gene and protein expression in scaffolds regularly used for tissue engineering approaches. METHODS: Collagen-based dermal regeneration matrices (DRM) were seeded with human umbilical vein endothelial cells (HUVEC), human dermal lymphatic endothelial cells (LECs), or adipose-derived stem cells (ASC) and fixed with or without fibrin glue according to the experimental group. Cultures were maintained for 1 and 7 days. Finally, angiogenic and lymphangiogenic gene and protein expression were measured with special regard to subtypes of vascular endothelial growth factor (VEGF) and corresponding receptors using Multiplex-qPCR and ELISA assays. In addition, the hypoxia-induced factor 1-alpha (HIF1a) mediated intracellular signaling pathways were included in assessments to analyze a hypoxic encapsulating effect of fibrin polymers. RESULTS: All cell types reacted to fibrin glue application with an alteration of gene and protein expression. In particular, vascular endothelial growth factor A (VEGFA), vascular endothelial growth factor B (VEGFB), vascular endothelial growth factor C (VEGFC), vascular endothelial growth receptor 1 (VEGFR1/FLT1), vascular endothelial growth receptor 2 (VEGFR2/KDR), vascular endothelial growth receptor 3 (VEGFR3/FLT4) and Prospero Homeobox 1 (PROX1) were depressed significantly depending on fibrin glue. Especially short-term fibrin effect led to a continuous downregulation of respective gene and protein expression in HUVECs, LECs, and ASCs. CONCLUSION: Our findings demonstrate the impact of fibrin glue application in dermal regeneration with special regard to angiogenesis and lymphangiogenesis. In particular, a short fibrin treatment of 24 hours led to a decrease in gene and protein levels of LECS, HUVECs, and ASCs. In contrast, the long-term application showed less effect on gene and protein expressions. Therefore, this work demonstrated the negative effects of fibrin-treated cells in tissue engineering approaches and could affect wound healing during dermal regeneration.

Adipose-Derived Stem Cells Improve Angiogenesis and Lymphangiogenesis in a Hypoxic Dermal Regeneration Model In Vitro.

Background and Objectives: Impaired wound healing represents an unsolved medical issue with a high impact on patients' quality of life and global health care. Even though hypoxia is a significant limiting factor for wound healing, it reveals stimulating effects in gene and protein expression at cellular levels. In particular, hypoxically treated human adipose tissue-derived stem cells (ASCs) have previously been used to stimulate tissue regeneration. Therefore, we hypothesized that they could promote lymphangiogenesis or angiogenesis. Materials and Methods: Dermal regeneration matrices were seeded with human umbilical vein endothelial cells (HUVECs) or human dermal lymphatic endothelial cells (LECs) that were merged with ASCs. Cultures were maintained for 24 h and 7 days under normoxic or hypoxic conditions. Finally, gene and protein expression were measured regarding subtypes of VEGF, corresponding receptors, and intracellular signaling pathways, especially hypoxia-inducible factor-mediated pathways using multiplex-RT-qPCR and ELISA assays. Results: All cell types reacted to hypoxia with an alteration of gene expression. In particular, vascular endothelial growth factor A (VEGFA), vascular endothelial growth factor B (VEGFB), vascular endothelial growth factor C (VEGFC), vascular endothelial growth factor receptor 1 (VEGFR1/FLT1), vascular endothelial growth factor receptor 2 (VEGFR2/KDR), vascular endothelial growth factor receptor 3 (VEGFR3/FLT4), and prospero homeobox 1 (PROX1) were overexpressed significantly depending on upregulation of hypoxia-inducible factor 1 alpha (HIF-1a). Moreover, co-cultures with ASCs showed a more intense change in gene and protein expression profiles and gained enhanced angiogenic and lymphangiogenic potential. In particular, long-term hypoxia led to continuous stimulation of HUVECs by ASCs. Conclusions: Our findings demonstrated the benefit of hypoxic conditioned ASCs in dermal regeneration concerning angiogenesis and lymphangiogenesis. Even a short hypoxic treatment of 24 h led to the stimulation of LECs and HUVECs in an ASC-co-culture. Long-term hypoxia showed a continuous influence on gene expressions. Therefore, this work emphasizes the supporting effects of hypoxia-conditioned-ASC-loaded collagen scaffolds on wound healing in dermal regeneration.

Efficacy of perioperative antibiotic prophylaxis in elective soft-tissue-only wrist arthroscopy.

Wrist arthroscopy is a standard procedure in hand surgery for diagnosis and treatment of wrist injuries. Even though not generally recommended for similar procedures, general administration of perioperative antibiotic prophylaxis (PAP) is still widely used in wrist arthroscopy. A clinical ambispective dual-centre study was performed to determine whether PAP reduces postoperative infection rates after soft tissue-only wrist arthroscopies. Retrospective and prospective data was collected at two hospitals with departments specialized in hand surgery. During the study period, 464 wrist arthroscopies were performed, of these 178 soft-tissue-only interventions met the study criteria and were included. Signs of postoperative infection and possible adverse drug effects (ADEs) of PAP were monitored. Additionally, risk factors for surgical site infection (SSIs), such as diabetes mellitus and BMI, were obtained. The overall infection rate of SSI was zero. Neither in the PAP group (n = 69) nor in the control group (n = 109) were signs of postoperative infection observed. Observed symptoms of ADEs were three-times higher in the PAP group when compared to the control-group (16.3 vs 5.5%; p = 0.043). No major ADEs were observed, but one in ten patients in the PAP group reported mild to severe intestinal or hypersensitivity symptoms. We demonstrate that the number needed to treat (NNT) with PAP to prevent one postoperative infection in soft-tissue arthroscopies of the wrist is > 109. Conversely, symptoms of ADEs were reported by one out of ten patients given PAP. Considering the high NNT to prevent postoperative infection and the large number of ADEs caused by PAP, we recommend not to use PAP routinely in soft-tissue arthroscopies of the wrist. Subsequent large-scale studies should be conducted to substantiate these results.