Risk factors of major complications after flap surgery in the treatment of stage III and IV pressure injury in people with spinal cord injury/disorder: a retrospective cohort study.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: To identify risk factors associated with major complications after flap surgery in people with spinal cord injury or disorder (SCI/D) and stage III and IV pressure injury (PI). SETTING: Swiss hospital specialized in the treatment of people with SCI/D using the Basel Decubitus Approach. METHODS: We examined 60 risk factors for major postoperative complications in PIs over sacrum/coccyx, ischium or trochanter between 01/2016 and 12/2021. We performed descriptive analysis and computed global p-values using likelihood ratio tests adjusted for clustering of PIs in individuals. RESULTS: We included 220 PI treatment procedure from 149 individuals. The study population consisted of 163 (74%) men, 133 (60%) traumatic SCI, 136 (58%) stage IV PI, 198 (90%) individuals with paraplegia, 93 (42%) with osteomyelitis, and 85 (39%) with recurrent PI. Major complications 42 (19%) occurred more often in individuals with stage IV PI (p < 0.01), individuals without osteomyelitis (p < 0.03), and individuals with pathological blood concentrations of cystatin c (p < 0.028), calcium (p < 0.048), and vitamin B12 (p < 0.0049) as well as normal blood concentrations of HbA1c (p < 0.033). Immobilization (p < 0.0089) and hospital stay (p < 0.0001) of individuals with major complications was longer. CONCLUSION: In the Basel Decubitus Approach, stage IV PI, absence of osteomyelitis, reduced vitamin B12 and calcium, elevated cystatin c, and normal HbA1c should be addressed to reduce major complications.

Combining reconstructive and ablative surgical treatment of chronic breast cancer-related lymphedema (BCRL): safe and effective.

PURPOSE: We investigated whether a one-stage combination of vascularized lymph node transfer (VLNT) with water jet-assisted liposuction (WAL) can be safely performed and results in improved patient outcomes such as a greater reduction in arm volume when treating chronic breast cancer-related lymphedema (BCRL). METHODS: In this retrospective cohort study, we included all patients from our encrypted lymphedema database treated for chronic BCRL with VLNT or VLNT + WAL who had a minimum follow-up of two years. We analyzed patient-specific variables including arm circumferences as well as patient-reported outcomes before and after surgery as well as surgery time, surgery-related complications and patient satisfaction. RESULTS: Only the mean preoperative differences of the circumferences between the lymphedematous and the unaffected arm in individual patients showed a statistically significant difference between treatment groups (p < 0.05). Indeed, patients treated with VLNT + WAL had consistently larger differences in individual sets of arms and therefore more pronounced chronic BCRL. The mean surgery time was significantly longer in the VLNT + WAL group (p < 0.05). Complications were seldom and similar in both groups. Using a numeric rating scale, the level of patient satisfaction following treatment did not differ significantly between groups (p = 0.323). CONCLUSIONS: Our findings suggest that a one-stage combination of VLNT with WAL does not result in more complications even though it also entails a longer surgery time. This is acceptable as secondary interventions resulting in overall longer surgery times and higher costs can be avoided. A one-stage combination might be especially favourable for patients suffering from more severe chronic BCRL.

Identification of microorganisms by a rapid PCR panel from positive blood cultures leads to faster optimal antimicrobial therapy - a before-after study.

BACKGROUND: The BioFire® FilmArray® Blood Culture Identification Panel 1 (BF-FA-BCIP) detects microorganisms with high accuracy in positive blood cultures (BC) - a key step in the management of patients with suspected bacteraemia. We aimed to compare the time to optimal antimicrobial therapy (OAT) for the BF-FA-BCIP vs. standard culture-based identification. METHODS: In this retrospective single-centre study with a before-after design, 386 positive BC cases with identification by BF-FA-BCIP were compared to 414 controls with culture-based identification. The primary endpoint was the time from BC sampling to OAT. Secondary endpoints were time to effective therapy, length of stay, (re-)admission to ICU, in-hospital and 30-day mortality. Outcomes were assessed using Cox proportional hazard models and logistic regressions. RESULTS: Baseline characteristics of included adult inpatients were comparable. Main sources of bacteraemia were urinary tract and intra-abdominal infection (19.2% vs. 22.0% and 16.8% vs. 15.7%, for cases and controls, respectively). Median (95%CI) time to OAT was 25.5 (21.0-31.2) hours with BF-FA-BCIP compared to 45.7 (37.7-51.4) hours with culture-based identification. We observed no significant difference for secondary outcomes. CONCLUSIONS: Rapid microorganism identification by BF-FA-BCIP was associated with a median 20-h earlier initiation of OAT in patients with positive BC. No impact on length of stay and mortality was noted. TRIAL REGISTRATION: Clinicaltrials.gov, NCT04156633, registered on November 5, 2019.

Mesenchymal Stem Cells in Nerve Tissue Engineering: Bridging Nerve Gap Injuries in Large Animals.

Cell-therapy-based nerve repair strategies hold great promise. In the field, there is an extensive amount of evidence for better regenerative outcomes when using tissue-engineered nerve grafts for bridging severe gap injuries. Although a massive number of studies have been performed using rodents, only a limited number involving nerve injury models of large animals were reported. Nerve injury models mirroring the human nerve size and injury complexity are crucial to direct the further clinical development of advanced therapeutic interventions. Thus, there is a great need for the advancement of research using large animals, which will closely reflect human nerve repair outcomes. Within this context, this review highlights various stem cell-based nerve repair strategies involving large animal models such as pigs, rabbits, dogs, and monkeys, with an emphasis on the limitations and strengths of therapeutic strategy and outcome measurements. Finally, future directions in the field of nerve repair are discussed. Thus, the present review provides valuable knowledge, as well as the current state of information and insights into nerve repair strategies using cell therapies in large animals.

An Updated Definition of Plastic Surgery.

ABSTRACT: Modern medicine tends to provide comprehensive medical services based on disease or pathological features. As a result, the overlap between plastic surgery and other surgical departments greatly deepened. What was exclusively done by plastic surgeons are nowadays frequently practiced by other surgeons as well. Thus, generating confusion as to whether plastic surgery is an independent subject or a tool. Therefore, in this new era of modern medicine, it is necessary to reconsider the definition of plastic surgery.

High Mortality of Non-Fournier Necrotizing Fasciitis With Enterobacteriales: Time to Rethink Classification?

This cohort study describes mortality predictors of necrotizing fasciitis (NF). Higher age, chronic kidney disease, and higher Charlson score increased the mortality rate. Mortality was >3 times higher in monomicrobial gram-negative NF than in type I or type II NF. Highest mortality was found with Enterobacteriales in non-Fournier NF.

Nutritional blood parameters and nutritional risk screening in patients with spinal cord injury and deep pressure ulcer-a retrospective chart analysis.

STUDY DESIGN: Retrospective chart review. OBJECTIVES: To describe (i) the nutritional blood parameters (NBP) and the nutritional risk screening (NRS) in patients with spinal cord injury (SCI) and pressure ulcers (PU) III and IV according to the EPUAP classification, and (ii) the relationship between both NBP and NRS. SETTING: SCI acute care and rehabilitation clinic in Switzerland. METHODS: The NBPs were measured upon the admission of patients treated for PU III and IV between 11/2011 and 12/2014. Descriptive analyses and group comparisons were done. RESULTS: A total of 170 patients, including 42 (25%) women, 19 (12%) people with paraplegia and 104 (61%) people with traumatic SCI, were admitted and analyzed. Pathologic blood values and NBP were found for c-reactive protein (83%), vitamin D (73%), protein (41%), erythrocyte sedimentation rate (ESR) (41%), albumin (34%), hemoglobin (34%), zinc (29%), folic acid (22%), transferrin (15.3%), and copper (1.2%). Overall, the NRS was >3 in 39% of the patients, wherefrom 28% in patients with PU III and 44% with PU IV (p=0.07). No statistical significant differences were found between patients with PU III and IV in terms of NBP and NRS. CONCLUSIONS: We found abnormal values in NBP and in NRS in a significant number of patients with SCI and PU of both III and IV. Both laboratory examinations and nutritional assessments at admission can help to detect and correct the nutritional deficits in patients at risk. Neither the grade of the PUs, nor the NBP or the NRS can replace one another.

Extending the limits of the anterior tibial artery as the recipient vessel for around the knee and proximal lower extremity defect reconstruction using the free anterolateral thigh and gracilis flap.

PURPOSE: The aim is to describe a technique with orthograde dissection of the anterior tibial artery (ATA) used as the recipient vessel for the end-to-end (ETE) anastomosis in defect reconstruction around the knee and for proximal/middle third leg defects with free anterolateral thigh (ALT) and gracilis flaps. PATIENTS AND METHODS: Between March 2009 and May 2014, 22 patients undergoing lower extremity reconstruction were evaluated. Of those, 4 patients were included. The locations of injury were 3 defects around the knee and 1 defect at the proximal and middle third of the lower leg (mean defect size 18 x 8.5 cm and a range of 17-20 x 5-10 cm). There were 2 cases after trauma and 2 cases with infection. Two free gracilis and 2 free ALT flaps were performed of equal size to the defects. The mean flap pedicle length was 11 cm (range of 7-16 cm) and the mean length of the mobilized recipient vessels was 10.5 cm (range of 6-14 cm). RESULTS: One flap loss (ALT) occurred, requiring a salvage procedure with a latissimus dorsi flap, whereas wound dehiscence at the donor site and a hematoma below the ALT flap was observed in 2 cases, requiring small revision. After a mean follow-up of 52 months (range of 38-87 months), there was stable soft tissue coverage in all patients. CONCLUSION: By orthograde dissection of the ATA, an adequate vessel length and size may be achieved, improving arc of rotation to successfully cover more distant defects.

From Bedside to Bench: The Effect of Muscular Denervation on Fat Grafting to the Breast by Comparing Take Rate, Quality, and Longevity.

BACKGROUND: Autologous fat grafting (AFG) to the breast is a frequent procedure in aesthetic and reconstructive surgery. Despite pure volume gain, questions remain regarding the engraftment rate, quality, and longevity. Little is known about the role of recipient tissue or innervation of the grafted area. OBJECTIVES: The goal of this study was to determine the optimal recipient layer and muscular pretreatment of AFG. METHODS: Fat was grafted to the breast, pectoralis muscle, or adjacent subcutaneous tissue of 42 rats. Nerve treatment included excision of a nerve segment, botulinum toxin (BTX) injection, or no treatment. Magnetic resonance imaging (MRI) and histological workup were carried out after 2 and 6 weeks. RESULTS: Six weeks after AFG, the proportion of viable fat cells within the grafted fat stayed high (median, [IQR]: 81% [72% to 85%]). The signs of inflammation decreased over time. Intramuscular grafting with intact nerves had a decreasing effect on the viability of the grafted cells compared with subcutaneous treatment (-10.21%; 95% confidence interval [-21.1 to 0.68]). CONCLUSIONS: If utilized on an intact nerve, intramuscular injection may lead to inferior results. If the nerve was cut or treated with BTX; however, intramuscular injection tends to be superior. These findings may prove interesting for future studies and eventual clinical application.

Nasal chondrocyte-based engineered autologous cartilage tissue for repair of articular cartilage defects: an observational first-in-human trial.

BACKGROUND: Articular cartilage injuries have poor repair capacity, leading to progressive joint damage, and cannot be restored predictably by either conventional treatments or advanced therapies based on implantation of articular chondrocytes. Compared with articular chondrocytes, chondrocytes derived from the nasal septum have superior and more reproducible capacity to generate hyaline-like cartilage tissues, with the plasticity to adapt to a joint environment. We aimed to assess whether engineered autologous nasal chondrocyte-based cartilage grafts allow safe and functional restoration of knee cartilage defects. METHODS: In a first-in-human trial, ten patients with symptomatic, post-traumatic, full-thickness cartilage lesions (2-6 cm2) on the femoral condyle or trochlea were treated at University Hospital Basel in Switzerland. Chondrocytes isolated from a 6 mm nasal septum biopsy specimen were expanded and cultured onto collagen membranes to engineer cartilage grafts (30 × 40 × 2 mm). The engineered tissues were implanted into the femoral defects via mini-arthrotomy and assessed up to 24 months after surgery. Primary outcomes were feasibility and safety of the procedure. Secondary outcomes included self-assessed clinical scores and MRI-based estimation of morphological and compositional quality of the repair tissue. This study is registered with ClinicalTrials.gov, number NCT01605201. The study is ongoing, with an approved extension to 25 patients. FINDINGS: For every patient, it was feasible to manufacture cartilaginous grafts with nasal chondrocytes embedded in an extracellular matrix rich in glycosaminoglycan and type II collagen. Engineered tissues were stable through handling with forceps and could be secured in the injured joints. No adverse reactions were recorded and self-assessed clinical scores for pain, knee function, and quality of life were improved significantly from before surgery to 24 months after surgery. Radiological assessments indicated variable degrees of defect filling and development of repair tissue approaching the composition of native cartilage. INTERPRETATION: Hyaline-like cartilage tissues, engineered from autologous nasal chondrocytes, can be used clinically for repair of articular cartilage defects in the knee. Future studies are warranted to assess efficacy in large controlled trials and to investigate an extension of indications to early degenerative states or to other joints. FUNDING: Deutsche Arthrose-Hilfe.

Implantation of Stromal Vascular Fraction Progenitors at Bone Fracture Sites: From a Rat Model to a First-in-Man Study.

Stromal Vascular Fraction (SVF) cells freshly isolated from adipose tissue include osteogenic- and vascular-progenitors, yet their relevance in bone fracture healing is currently unknown. Here, we investigated whether human SVF cells directly contribute to the repair of experimental fractures in nude rats, and explored the feasibility/safety of their clinical use for augmentation of upper arm fractures in elderly individuals. Human SVF cells were loaded onto ceramic granules within fibrin gel and implanted in critical nude rat femoral fractures after locking-plate osteosynthesis, with cell-free grafts as control. After 8 weeks, only SVF-treated fractures did not fail mechanically and displayed formation of ossicles at the repair site, with vascular and bone structures formed by human cells. The same materials combined with autologous SVF cells were then used to treat low-energy proximal humeral fractures in 8 patients (64-84 years old) along with standard open reduction and internal fixation. Graft manufacturing and implantation were compatible with intraoperative settings and led to no adverse reactions, thereby verifying feasibility/safety. Biopsies of the repair tissue after up to 12 months, upon plate revision or removal, demonstrated formation of bone ossicles, structurally disconnected and morphologically distinct from osteoconducted bone, suggesting the osteogenic nature of implanted SVF cells. We demonstrate that SVF cells, without expansion or exogenous priming, can spontaneously form bone tissue and vessel structures within a fracture-microenvironment. The gained clinical insights into the biological functionality of the grafts, combined with their facile, intra-operative manufacturing modality, warrant further tests of effectiveness in larger, controlled trials. Stem Cells 2016;34:2956-2966.

Evaluation of the Neo-umbilicus Cutaneous Sensitivity Following Abdominoplasty.

BACKGROUND: Abdominal cutaneous sensitivity loss after abdominoplasty is an undesirable outcome. However, little is known in the literature about sensitivity changes of the neo-umbilicus after abdominoplasty. The aim of this study was to evaluate post-abdominoplasty cutaneous sensitivity of the neo-umbilicus using clinical, quantitative, and reproducible methods. METHODS: Patients who underwent abdominoplasty were included, whereas the control group consisted of healthy volunteers with similar demographic characteristics but who did not undergo abdominoplasty. The umbilicus was divided into five zones, and superficial tactile sensitivity and spatial orientation were assessed subjectively (score 1-4) and objectively (Semmes-Weinstein monofilament examination). RESULTS: Twenty patients (45 ± 12 years) operated on consecutively between April 2012 and May 2016 and 14 healthy volunteers in the control group (39 ± 9 years) could be included. Although there were statistically significant differences (p = 0.0005) in the average cutaneous pressure thresholds between the control group (0.4 g/mm2, range 0.07-2 g/mm2) and the study group (0.4 g/mm2, range 0.07-4 g/mm2), patient satisfaction after a mean follow-up of 33 ± 16 months (range 10-62 months) was acceptable (mean satisfaction score 1.8 ± 0.7). Furthermore, spatial perceptions were precise in all patients and similar to the control group. CONCLUSION: Our long-term results indicate that spontaneous reinnervation of the neo-umbilicus after abdominoplasty together with accurate spatial orientation can occur. 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 .

Ascorbic Acid Attenuates Senescence of Human Osteoarthritic Osteoblasts.

The accumulation of senescent cells is implicated in the pathology of several age-related diseases. While the clearance of senescent cells has been suggested as a therapeutic target for patients with osteoarthritis (OA), cellular senescence of bone-resident osteoblasts (OB) remains poorly explored. Since oxidative stress is a well-known inducer of cellular senescence, we here investigated the effect of antioxidant supplementation on the isolation efficiency, expansion, differentiation potential, and transcriptomic profile of OB from osteoarthritic subchondral bone. Bone chips were harvested from sclerotic and non-sclerotic regions of the subchondral bone of human OA joints. The application of 0.1 mM ascorbic acid-2-phosphate (AA) significantly increased the number of outgrowing cells and their proliferation capacity. This enhanced proliferative capacity showed a negative correlation with the amount of senescent cells and was accompanied by decreased expression of reactive oxygen species (ROS) in cultured OB. Expanded cells continued to express differentiated OB markers independently of AA supplementation and demonstrated no changes in their capacity to osteogenically differentiate. Transcriptomic analyses revealed that apoptotic, cell cycle-proliferation, and catabolic pathways were the main pathways affected in the presence of AA during OB expansion. Supplementation with AA can thus help to expand subchondral bone OB in vitro while maintaining their special cellular characteristics. The clearance of such senescent OB could be envisioned as a potential therapeutic target for the treatment of OA.

Gluteal Augmentation Techniques: A Comprehensive Literature Review.

Background: Many studies of gluteal augmentation techniques have been published in recent decades, including case reports, retrospective and prospective case series, and multicenter survey reviews. However, to date, there has been no study of the overall complications or satisfaction rates associated with the broad spectrum of techniques. Objectives: The authors performed a comprehensive literature review to determine outcomes and complications of gluteoplasty techniques, including patient satisfaction. Methods: A search on PubMed/Medline was performed for clinical studies involving gluteal augmentation techniques. A priori criteria were used to review the resulting articles. Results: Fifty-two studies, published from 1969 through 2015, were included - representing 7834 treated patients. Five gluteal augmentation techniques were identified from these studies: gluteal augmentation with implants (n = 4781), autologous fat grafting (n = 2609), local flaps (n = 369), hyaluronic acid gel injection (n = 69), and local tissue rearrangement (n = 6). The overall complication rates of the most commonly utilized techniques were: 30.5% for gluteal augmentation with implants, 10.5% for autologous fat grafting, and 22% for local flaps. Patients' satisfaction was reported as consistently high for all the five techniques. Conclusions: Implant-based gluteal augmentation is associated with high patients' satisfaction despite a high complication rate, while autologous fat grafting is associated with the lowest complication rate yet including serious major complications such as fat embolism. Local flaps and local tissue rearrangements are the ideal procedures in case of massive weight loss patients. A paucity of data is available for hyaluronic acid gel injections, which appear to be effective but temporary and expensive.

Adipose-Derived Stromal Cells from Lipomas: Isolation, Characterisation and Review of the Literature.

OBJECTIVE: The aim of this study was to characterize adipose-derived stromal cells (ADSCs) from patients diagnosed with multiple symmetric lipomatosis (MSL) in order to obtain potentially new insights into the pathophysiology, pathogenesis and treatment of this disease. METHODS: Cells from the stromal vascular fraction were analysed by the colony-forming efficiency assay and flow cytometry using standard markers. Moreover, the power of adipogenic plasticity was evaluated. Finally, a literature review was performed from 1982 to 2015 using the US National Institutes of Health's PubMed database. RESULTS: Three European-descent patients diagnosed with either MSL type I or II could be identified for analysis. The resulting mean colony-forming efficiency assay was 14.3 ± 5%. Flow-cytometric analysis of the ADSCs revealed high levels of CD34 (70 ± 9%), CD45 (37 ± 13%) and CD73 (55.8 ± 14%), whereas low levels of CD31 (16.8 ± 14%) and CD105 (5.8 ± 0.7%) were detected. Furthermore, ADSCs showed a strong adipogenic potential, which is in line with the literature review. The stem cell pool in lipoma shows several alterations in biological activities, such as proliferation, apoptosis and stemness. CONCLUSIONS: ADSCs from lipoma may be interesting in the application of regenerative medicine. We discuss possible molecular treatment options to regulate their activities at the source of the MSL.

Engineered autologous cartilage tissue for nasal reconstruction after tumour resection: an observational first-in-human trial.

BACKGROUND: Autologous native cartilage from the nasal septum, ear, or rib is the standard material for surgical reconstruction of the nasal alar lobule after two-layer excision of non-melanoma skin cancer. We assessed whether engineered autologous cartilage grafts allow safe and functional alar lobule restoration. METHODS: In a first-in-human trial, we recruited five patients at the University Hospital Basel (Basel, Switzerland). To be eligible, patients had to be aged at least 18 years and have a two-layer defect (≥50% size of alar subunit) after excision of non-melanoma skin cancer on the alar lobule. Chondrocytes (isolated from a 6 mm cartilage biopsy sample from the nasal septum harvested under local anaesthesia during collection of tumour biopsy sample) were expanded, seeded, and cultured with autologous serum onto collagen type I and type III membranes in the course of 4 weeks. The resulting engineered cartilage grafts (25 mm × 25 mm × 2 mm) were shaped intra-operatively and implanted after tumour excision under paramedian forehead or nasolabial flaps, as in standard reconstruction with native cartilage. During flap refinement after 6 months, we took biopsy samples of repair tissues and histologically analysed them. The primary outcomes were safety and feasibility of the procedure, assessed 12 months after reconstruction. At least 1 year after implantation, when reconstruction is typically stabilised, we assessed patient satisfaction and functional outcomes (alar cutaneous sensibility, structural stability, and respiratory flow rate). FINDINGS: Between Dec 13, 2010, and Feb 6, 2012, we enrolled two women and three men aged 76-88 years. All engineered grafts contained a mixed hyaline and fibrous cartilage matrix. 6 months after implantation, reconstructed tissues displayed fibromuscular fatty structures typical of the alar lobule. After 1 year, all patients were satisfied with the aesthetic and functional outcomes and no adverse events had been recorded. Cutaneous sensibility and structural stability of the reconstructed area were clinically satisfactory, with adequate respiratory function. INTERPRETATION: Autologous nasal cartilage tissues can be engineered and clinically used for functional restoration of alar lobules. Engineered cartilage should now be assessed for other challenging facial reconstructions. FUNDING: Foundation of the Department of Surgery, University Hospital Basel; and Krebsliga beider Basel.

Phase II metabolism in human skin: skin explants show full coverage for glucuronidation, sulfation, N-acetylation, catechol methylation, and glutathione conjugation.

Although skin is the largest organ of the human body, cutaneous drug metabolism is often overlooked, and existing experimental models are insufficiently validated. This proof-of-concept study investigated phase II biotransformation of 11 test substrates in fresh full-thickness human skin explants, a model containing all skin cell types. Results show that skin explants have significant capacity for glucuronidation, sulfation, N-acetylation, catechol methylation, and glutathione conjugation. Novel skin metabolites were identified, including acyl glucuronides of indomethacin and diclofenac, glucuronides of 17ß-estradiol, N-acetylprocainamide, and methoxy derivatives of 4-nitrocatechol and 2,3-dihydroxynaphthalene. Measured activities for 10 µM substrate incubations spanned a 1000-fold: from the highest 4.758 pmol·mg skin(-1)·h(-1) for p-toluidine N-acetylation to the lowest 0.006 pmol·mg skin(-1)·h(-1) for 17ß-estradiol 17-glucuronidation. Interindividual variability was 1.4- to 13.0-fold, the highest being 4-methylumbelliferone and diclofenac glucuronidation. Reaction rates were generally linear up to 4 hours, although 24-hour incubations enabled detection of metabolites in trace amounts. All reactions were unaffected by the inclusion of cosubstrates, and freezing of the fresh skin led to loss of glucuronidation activity. The predicted whole-skin intrinsic metabolic clearances were significantly lower compared with corresponding whole-liver intrinsic clearances, suggesting a relatively limited contribution of the skin to the body's total systemic phase II enzyme-mediated metabolic clearance. Nevertheless, the fresh full-thickness skin explants represent a suitable model to study cutaneous phase II metabolism not only in drug elimination but also in toxicity, as formation of acyl glucuronides and sulfate conjugates could play a role in skin adverse reactions.

Poly-N-acetyl glucosamine nanofibers for negative-pressure wound therapies.

The wound healing promoting effect of negative wound pressure therapies (NPWT) takes place at the wound interface. The use of bioactive substances at this site represents a major research area for the development of future NPWT therapies. To assess wound healing kinetics in pressure ulcers treated by NPWT with or without the use of a thin interface membrane consisting of poly-N-acetyl glucosamine nanofibers (sNAG) a prospective randomized clinical trial was performed. The safety of the combination of NPWT and sNAG was also assessed in patients treated with antiplatelet drugs. In the performed study, the combination of NPWT and sNAG in 10 patients compared to NPWT alone in 10 patients promoted wound healing due to an improved contraction of the wound margins (p = 0.05) without a change in wound epithelization. In 6 patients treated with antiplatelet drugs no increased wound bleeding was observed in patients treated by NPWT and sNAG. In conclusion, the application of thin membranes of sNAG nanofibers at the wound interface using NPWT was safe and augmented the action of NPWT leading to improved wound healing due to a stimulation of wound contraction.

The Combined Pedicled Anterolateral Thigh and Vastus Lateralis Flap as Filler for Complex Perineal Defects.

Extensive defects of the pelvis and genitoperineal region are a reconstructive challenge. We discuss a consecutive series of 25 reconstructions with the pedicled anterolateral thigh (ALT) flap including muscle part of the vastus lateralis (VL) in 23 patients from October 1999 to September 2012.Only surface defects larger than 100 cm and reconstructions by composite ALT + VL were included in this retrospective analysis. Of the 23 patients, 19 underwent oncologic resection, whereas 4 cases presented Fournier gangrene. Three patients did not reach 6 months of follow-up and were excluded from further data analysis. Among the remaining 20 patients (22 reconstructions), average follow-up period was 14 months (range, 10-18 months). Patient's average age was 60 years. Average size of the defect was 182 cm.Postoperative complications included 1 (4.5%) flap necrosis out of 22 raised flaps, 1 partial flap necrosis after venous congestion, and 2 cases where a complementary reconstructive procedure was performed due to remaining defect or partial flap failure. In 6 cases, peripheral wound dehiscence (27%) was treated by debridement followed by split-thickness skin graft or advancement local flaps. Defect size was significantly related to postoperative complications and increased hospital stay, especially in those patients who underwent preoperative radiotherapy. At the end of the follow-up period, a long-term and satisfactory coverage was obtained in all patients without functional deficits.This consecutive series of composite ALT + VL flap shows that, in case of extended defects, the flap provides an excellent and adjustable muscle mass, is reliable with minimal donor-site morbidity, and can even be designed as a sensate flap.

Engraftment of Prevascularized, Tissue Engineered Constructs in a Novel Rabbit Segmental Bone Defect Model.

The gold standard treatment of large segmental bone defects is autologous bone transfer, which suffers from low availability and additional morbidity. Tissue engineered bone able to engraft orthotopically and a suitable animal model for pre-clinical testing are direly needed. This study aimed to evaluate engraftment of tissue-engineered bone with different prevascularization strategies in a novel segmental defect model in the rabbit humerus. Decellularized bone matrix (Tutobone) seeded with bone marrow mesenchymal stromal cells was used directly orthotopically or combined with a vessel and inserted immediately (1-step) or only after six weeks of subcutaneous "incubation" (2-step). After 12 weeks, histological and radiological assessment was performed. Variable callus formation was observed. No bone formation or remodeling of the graft through TRAP positive osteoclasts could be detected. Instead, a variable amount of necrotic tissue formed. Although necrotic area correlated significantly with amount of vessels and the 2-step strategy had significantly more vessels than the 1-step strategy, no significant reduction of necrotic area was found. In conclusion, the animal model developed here represents a highly challenging situation, for which a suitable engineered bone graft with better prevascularization, better resorbability and higher osteogenicity has yet to be developed.