Preoperative CT imaging as a tool to predict incisional hernia outcomes following abdominal wall reconstruction: A retrospective cohort analysis.

INTRODUCTION: Ventral wall hernia often causes significant morbidity and requires complex abdominal wall reconstruction (AWR). This study aims to determine whether subcutaneous abdominal fat thickness (AFT) measured with preoperative CT scans could predict postoperative outcomes in patients undergoing AWR. METHODS: A retrospective cohort study was conducted on all patients who underwent AWR at our institution between 2009 and 2021, with a minimum follow-up of 12 months. Using preoperative CT scans, AFT was measured at the xiphoid process, umbilicus, and pubic tubercle, as well as the hernia dimensions. Demographic, operative, and surgical outcome data were also collected and analyzed using statistical tests. RESULTS: The results showed that 9 of 101 patients (8.9%) experienced hernia recurrence. Smoking was associated with an increased risk of hernia recurrence (p < 0.001) with a predictive odds ratio (OR) of 18.27 (p = 0.041). Increased AFT at the xiphoid (p = 0.005), umbilicus (p < 0.001), and pubic tubercle (p < 0.001) were also associated with hernia recurrence and risk of infection. Only AFT at the pubic tubercle reached significance in the regression model predicting recurrence (OR=1.10; p = 0.030) and infection (OR=1.04; p = 0.021). A cut-off value of 67 mm was associated with a positive predictive value of 42.14% (sensitivity of 67% and specificity of 91%). Hernia defect area was not associated with risk of recurrence or infection. CONCLUSIONS: Smoking and increased AFT at the pubic tubercle are significant predictive factors for recurrence and infection in patients undergoing AWR, and preoperative optimization should focus on reducing these factors.

Achieving optimal clinical outcomes in autologous fat grafting: A systematic review of processing techniques.

BACKGROUND: Autologous fat grafting (AFG) is a versatile technique in reconstructive and cosmetic surgery. Graft processing is a key source of variability resulting in unreliable clinical outcomes, with no consensus on the optimal methodology. This systematic review identifies the evidence base supporting different processing paradigms. METHODS: A systematic literature search was conducted using the PubMed, Scopus and The Cochrane Foundation databases. Studies comparing AFG processing methods and reporting long-term patient outcomes were identified. RESULTS: Twenty-four studies (2413 patients) were identified. Processing techniques evaluated included centrifugation, decantation, washing, filtration, gauze rolling, as well as commercial devices and adipose-derived stem/stromal cell (ASC) enrichment methods. Objective volumetric and subjective patient-reported outcomes were discussed. There was a variable reporting of complications and volume retention rates. Complications were infrequent; palpable cysts (0-20%), surgical-site infections (0-8%) and fat necrosis (0-58.4%) were the most reported. No significant differences in long-term volume retention between techniques were found in AFG in the breast. In head and neck patients, greater volume retention was documented in ASC enrichment (64.8-95%) and commercial devices (41.2%) compared to centrifugation (31.8-76%). CONCLUSIONS: Graft processing through washing and filtration, including when incorporated into commercial devices, results in superior long-term outcomes compared to centrifugation and decantation methods. ASC enrichment methods and commercial devices seem to have superior long-term volume retention in facial fat grafting.

Chemical group-dependent plasma polymerisation preferentially directs adipose stem cell differentiation towards osteogenic or chondrogenic lineages.

Human adipose derived stem cells (ADSCs) are being explored for the repair of craniofacial defects due to their multi-differentiation potential and ease of isolation and expansion. Crucial to using ADSCs for craniofacial repair is the availability of materials with appropriate biomechanical properties that can support their differentiation into bone and cartilage. We tested the hypothesis that different modifications of chemical groups on the surface of a nanocomposite polymer could increase human ADSC adhesion and selectively enhance their osteogenic and chondrogenic differentiation. We show that the COOH modification significantly promoted initial cell adhesion and proliferation over 14days compared to NH2 surfaces. Expression of focal adhesion kinase and vinculin was enhanced after plasma surface polymerisation at 24h. The COOH modification significantly enhanced chondrogenic differentiation as indicated by up-regulation of aggrecan and collagen II transcripts. In contrast, NH2 group functionalised scaffolds promoted osteogenic differentiation with significantly enhanced expression of collagen I, alkaline phosphatase and osteocalcin both at the gene and protein level. Finally, chorioallantoic membrane grafting demonstrated that both NH2 and COOH functionalised scaffolds seeded with ADSCs were biocompatible and supported vessel ingrowth apparently to a greater degree than unmodified scaffolds. In summary, our study shows the ability to direct ADSC chondrogenic and osteogenic differentiation by deposition of different chemical groups through plasma surface polymerisation. Hence this approach could be used to selectively enhance bone or cartilage formation before implantation in vivo to repair skeletal defects. STATEMENT OF SIGNIFICANCE: Human adipose derived stem cells (hADSCs) are an exciting stem cell source for regenerative medicine due to their plentiful supply and ease of isolation. However, the optimal environmental cues to direct stem cells towards certain lineages change have to has not been identified. We have shown that by modifying the surface of the scaffold with specific chemical groups using plasma surface polymerisation techniques we can control ADSCs differentiation. This study shows that ADSCs can be differentiated towards osteogenic and chondrogenic lineages on amine (NH2) and carboxyl (COOH) modified scaffolds respectively. Plasma polymerisation can be easily applied to other biomaterial surfaces to direct stem cell differentiation for the regeneration of bone and cartilage.

Biomechanical Characterisation of the Human Auricular Cartilages; Implications for Tissue Engineering.

Currently, autologous cartilage provides the gold standard for auricular reconstruction. However, synthetic biomaterials offer a number of advantages for ear reconstruction including decreased donor site morbidity and earlier surgery. Critical to implant success is the material's mechanical properties as this affects biocompatibility and extrusion. The aim of this study was to determine the biomechanical properties of human auricular cartilage. Auricular cartilage from fifteen cadavers was indented with displacement of 1 mm/s and load of 300 g to obtain a Young's modulus in compression. Histological analysis of the auricle was conducted according to glycoprotein, collagen, and elastin content. The compression modulus was calculated for each part of the auricle with the tragus at 1.67 ± 0.61 MPa, antitragus 1.79 ± 0.56 MPa, concha 2.08 ± 0.70 MPa, antihelix 1.71 ± 0.63 MPa, and helix 1.41 ± 0.67 MPa. The concha showed to have a significantly greater Young's Elastic Modulus than the helix in compression (p < 0.05). The histological analysis demonstrated that the auricle has a homogenous structure in terms of chondrocyte morphology, extracellular matrix and elastin content. This study provides new information on the compressive mechanical properties and histological analysis of the human auricular cartilage, allowing surgeons to have a better understanding of suitable replacements. This study has provided a reference, by which cartilage replacements should be developed for auricular reconstruction.

Lipotransfer for radiation-induced skin fibrosis.

BACKGROUND: Radiation-induced fibrosis (RIF) is a late complication of radiotherapy that results in progressive functional and cosmetic impairment. Autologous fat has emerged as an option for soft tissue reconstruction. There are also sporadic reports suggesting regression of fibrosis following regional lipotransfer. This systematic review aimed to identify cellular mechanisms driving RIF, and the potential role of lipotransfer in attenuating these processes. METHODS: PubMed, OVID and Google Scholar databases were searched to identify all original articles regarding lipotransfer for RIF. All articles describing irradiated fibroblast or myofibroblast behaviour were included. Data elucidating the mechanisms of RIF, role of lipotransfer in RIF and methods to quantify fibrosis were extracted. RESULTS: Ninety-eight studies met the inclusion criteria. A single, definitive model of RIF is yet to be established, but four cellular mechanisms were identified through in vitro studies. Twenty-one studies identified connective tissue growth factor and transforming growth factor ß1 cytokines as drivers of fibrotic cascades. Hypoxia was demonstrated to propagate fibrogenesis in three studies. Oxidative stress from the release of reactive oxygen species and free radicals was also linked to RIF in 11 studies. Purified autologous fat grafts contain cellular and non-cellular properties that potentially interact with these processes. Six methods for quantifying fibrotic changes were evaluated including durometry, ultrasound shear wave elastography, thermography, dark field imaging, and laser Doppler and laser speckle flowmetry. CONCLUSION: Understanding how lipotransfer causes regression of RIF remains unclear; there are a number of new hypotheses for future research.

Biomechanical characterisation of the human nasal cartilages; implications for tissue engineering.

Nasal reconstruction is currently performed using autologous grafts provides but is limited by donor site morbidity, tissue availability and potentially graft failure. Additionally, current alternative alloplastic materials are limited by their high extrusion and infection rates. Matching mechanical properties of synthetic materials to the native tissue they are replacing has shown to be important in the biocompatibility of implants. To date the mechanical properties of the human nasal cartilages has not been studied in depth to be able to create tissue-engineered replacements with similar mechanical properties to native tissue. The young's modulus was characterized in compression on fresh-frozen human cadaveric septal, alar, and lateral cartilage. Due to the functional differences experienced by the various aspects of the septal cartilage, 16 regions were evaluated with an average elastic modulus of 2.72 ± 0.63 MPa. Furthermore, the posterior septum was found to be significantly stiffer than the anterior septum (p < 0.01). The medial and lateral alar cartilages were tested at four points with an elastic modulus ranging from 2.09 ± 0.81 MPa, with no significant difference between the cartilages (p < 0.78). The lateral cartilage was tested once in all cadavers with an average elastic modulus of 0.98 ± 0.29 MPa. In conclusion, this study provides new information on the compressive mechanical properties of the human nasal cartilage, allowing surgeons to have a better understanding of the difference between the mechanical properties of the individual nasal cartilages. This study has provided a reference, by which tissue-engineered should be developed for effective cartilage replacements for nasal reconstruction.

Necrotising soft tissue infection in a UK metropolitan population.

INTRODUCTION: Necrotising soft tissue infection (NSTI) is a rare but life threatening diagnosis. Geographic, economic and social variances influence presentation and prognosis. As the current literature does not reflect a UK metropolitan population, we conducted a retrospective chart review to establish pertinent features relevant to our practice. METHODS: Patients with histologically confirmed diagnoses of NSTI presenting to two London teaching hospitals between January 2007 and July 2013 were included in the study. Features of presentation, surgical and medical management, microbiological findings and outcome were evaluated. RESULTS: Twenty-four patients with histologically confirmed NSTI were included. Two age clusters were identified, with means of 46 years (standard deviation [SD]: 10 years) and 80 years (SD: 6 years). Pain, erythema and sepsis were common findings. Hypertension, hypercholesterolaemia and type II diabetes mellitus were common co-morbidities. A third of younger patients had human immunodeficiency virus or hepatitis C, with a quarter dependent on drugs and/or alcohol. The mean Laboratory Risk Indicator for Necrotising Fasciitis (LRINEC) score was 5.8 (SD: 3.3). The lower extremities, groin and perineum were common sites of infection. Fourteen patients required inotropic support and seventeen required transfusions. The median number of surgical procedures was 5 (range: 1-17). Group A Streptococcus was the most frequently identified pathogen. Five patients died. Being elderly, female sex and failure to use clindamycin as a first-line antibiotic were associated with significantly higher mortality. CONCLUSIONS: In contrast to other recent series, group A streptococcal monomicrobial NSTI remains the most common presentation in our population. Survival is anticipated in young patients, regardless of premorbid status. Elderly patients have a poor prognosis. The negative predictive value of the LRINEC score is questioned. Use of clindamycin as a first-line antibiotic is supported.

The psychological impact of split-thickness skin grafts.

OBJECTIVE: To measure the psychological distress associated with a split-thickness skin graft (STSG). METHOD: A retrospective postal questionnaire survey of 102 patients who had undergone a STSG procedure within the last 3.5 years. Outcomes measures included the Hospital Anxiety and Depression Scale (HADS), Derriford Appearance Scale (DAS-59) and subjective rating scales (SRS) of noticeability and worry about the grafted and donor area. RESUTLS: Scores on the SRS correlated positively with HADS and DAS-59 scores. Rates of anxiety were higher than depression (19% vs 13%, respectively). Greater than 10% of the sample experienced significant appearance-related distress when compared to standardised test norms. Concerns about the grafted area were higher than for the donor site, but those concerned about the graft were also likely to be concerned about the donor area. Aged (< 60 years) and reason for surgery (trauma as opposed to cancer) were associated with significantly higher scores on appearance measures. CONCLUSION: STSG is not associated with high levels of psychological distress, However, there is a small but significant monitory who experience appearance-related distress, low mood and anxiety who would benefit from targeted psychological intervention, Demographic factors, such as age or gender, and length of time since surgery, are not useful discriminators in identifying vulnerable individuals. Simple SRS of visibility and worry correlate significantly with standardised psychological measures. These can be used as a short and effective screening tool to identify individuals who would benefit from postoperative psychological input. DECLARATION OF INTERNET: There were no external sources sources of funding for this study. The authors have no conflicts of interest to declare.

Low priority? A cross sectional study of appearance anxiety in 500 consecutive referrals for cosmetic surgery.

Low priority treatment guidance is used in the National Health Service to manage requests for cosmetic surgery where there is no associated functional impairment. Provision is made in this guidance to provide surgery on exceptional grounds, and this may include significant psychological distress. However, without a good understanding of the common factors that underpin requests for surgery, ideally in the local population, it is very difficult to define an exception in a clear and consistent way. A prospective study of consecutive referrals for cosmetic surgery in an NHS plastic surgery unit was therefore completed over a five-year period. Five hundred and one men and women aged between 16 and 79 (mean 34.5 years) were assessed using standardised questionnaires and clinical interview carried out by two clinical psychologists specialising in the field. Results indicated very marked impact of appearance-related anxiety with significant withdrawal from social activities particularly intimate behaviour. Coping behaviours ranged from use of concealing clothing and complete social avoidance to ominous high risk strategies such as repeated pregnancy with late termination to maintain breast size. Treatment goals were predominantly psychosocial. High levels of psychological morbidity can be characterised as typical of people requesting cosmetic procedures in the NHS rather than exceptional, making the achievement of equitable access to limited resources impossible. Rather than define this population as 'low-priority', a constructive approach is to examine the utility of psychological interventions in a design which evaluates the comparative benefits of surgical and psychological approaches to management of appearance anxiety.

The role of disgust emotions in predicting self-management in wound care.

OBJECTIVE: An observation study, employing a nominal questionnaire, was conducted to explore the relationship between disgust emotions, response to surgical wounds and engagement in wound management. METHOD: A total of 101 patients were recruited at the Royal Free Hospital plastic surgery dressing clinic, following a variety of elective or emergency surgical procedures. Participants were asked to complete the Haidt Disgust Sensitivity Questionnaire and a Wound Management Questionnaire. Participants were observed during the consultation to assess characteristics of the wound and indicators of disgust. Data were analysed using analysis of variance (ANOVA) and Z-test, with the primary outcome measure being engagement in care, as rated by the dressing nurses. RESULTS: Mean disgust sensitivity was significantly higher in females and in those who were observed to avert their gaze or appeared tearful during the consultation. Sensitivity was lower in participants who felt able to help the nurse with their dressing, those able to clean their wound, and those able to do their own dressing at home and who were not worried about the appearance of their scar. Wound size and severity were also found to have a significant impact on engagement in care. CONCLUSION: Both biomedical factors, such as size and severity of a wound, and psychological factors, such as disgust sensitivity, are important in wound care. Screening for disgust sensitivity pre-operatively, in association with the modified Wound Management Questionnaire, has the potential to identify patients who are at risk of avoidant behaviour and to develop psychological interventions to promote wound self management.

Induction of tolerance to an allogeneic skin flap transplant in a preclinical large animal model.

Clinical composite tissue allotransplantation can adequately reconstruct defects that are not possible by other means. However, immunosuppressant toxicity limits the use of these techniques. Clinical attempts to reduce the amount of immunosuppression required by induction of an immunologically permissive state have so far been unsuccessful. The aim of this study was to induce tolerance in a preclinical large animal model. Donor hematopoietic stem cell (HSC) engraftment was induced by T-cell depletion, irradiation, and a short course of cyclosporine administered to the recipient, along with a hematopoietic cell infusion from a single haplotype major histocompatibility complex (MHC) mismatched donor. Skin was then allotransplanted from the donor. Both primarily vascularized skin flaps and secondarily vascularized conventional skin grafts were allotransplanted to investigate if the mode of transplantation affected outcome. Control animals received the skin allotransplants without conditioning. Tolerance was defined as no evidence of rejection at 90 days following transplantation. Conventional skin grafts only achieved prolonged survival (<65 days) in HSC-engrafted animals (P < .01). In contrast, there was indefinite skin flap survival with the achievement of tolerance in HSC-engrafted animals; this was confirmed on histology with donor-specific unresponsiveness on MLR and CML. Furthermore, a conventional skin donor graft subsequently applied to an animal tolerant to a skin flap was not rejected and did not trigger skin flap rejection. To our knowledge, this is the first time skin tolerance has been achieved across a MHC barrier in a large animal model. This is a significant step toward the goal of clinical skin tolerance induction.

Objective evidence for the use of polylactic acid implants in HIV-associated facial lipoatrophy using three-dimensional surface laser scanning and psychological assessment.

The advent of highly active antiretroviral therapy (HAART) has dramatically improved the life expectancy of people infected with human immunodeficiency virus (HIV). Although patients often have excellent disease control with these combinations of antiretrovirals, they are at risk for the multiple toxicities associated with these drugs. Facial lipoatrophy is a particularly distressing complication of some HAART regimes. This disfigurement can lead to significant psychosocial stress, resulting in decreased treatment compliance. Polylactic acid (PLA) facial implants provide a potential method of restoring a normal appearance. One hundred consecutive patients had a course of PLA facial implants. All patients were assessed clinically and had photographs, facial surface laser scans and completed psychological questionnaires throughout the course of treatment. After a mean of 4.85 treatments per patient, there were improvements in all measures. The mean clinical scores improved from a moderate-severe grade to none-mild grade after treatment. Three-dimensional (3D) laser surface scans showed a volume increase of 2.81 cc over the treated area of the cheek. There were significant improvements in all of the psychological measures. This study shows clear objective evidence of the psychological and physical benefit of PLA implants in HIV-associated facial lipodystrophy.

Immunosuppression in an emerging field of plastic reconstructive surgery: composite tissue allotransplantation.

Composite tissue transplantation (CTA) refers to the transplantation of an allograft consisting of heterogeneous cadaveric tissues. It provides a means of restoring structural, functional and aesthetic form in severely injured patients. Recent progress in facial transplantation has highlighted the immense strides made in this field of reconstructive surgery. However the potential for improvements in quality of life must be offset by the need for life-long immunosuppression in adults with non life-threatening injuries. The benefits and difficulties of immunosuppressive drugs have been established in solid organ transplantation. Regimens derived from renal transplantation have been successfully applied to CTA. However the published incidence of complications seen in organ transplant recipients may not be easily extrapolated to potential CTA candidates and may be overstated. Accepted views that high dose immunosuppression would be needed to overcome highly antigenic tissues such as skin have not been borne out by clinical experience. It is therefore important to assess the current state of affairs, attempt to quantify the perceived risks and explore novel research methods being investigated. In doing so one can make a well-informed judgment of the potential benefit of this surgical modality as an integral part of the reconstructive ladder.

Diagnostic fine-needle aspiration in postoperative wound infections is more accurate at predicting causative organisms than wound swabs.

INTRODUCTION: Postoperative wound infections are common. Antibiotics are often prescribed empirically, usually in the absence of any microbiological sensitivity data. This study demonstrates the role of fine-needle aspiration microbiology (FNAM) in determining the causative organisms in these wounds compared to wound swabs taken from the same patients. PATIENTS AND METHODS: A total of 20 patients with clinical signs of soft tissue infection were tested using wound swabs and fine-needle aspiration. RESULTS: Six of the wound swabs yielded a single organism but 16 out 20 of the FNAM group yielded a single organism (P = 0.002). CONCLUSIONS: The FNAM approach allows antibiotic sensitivities to be obtained enabling specific antimicrobial therapy to be implemented early. FNAM also has a higher yield of cultures than wound swabs. Cellulitic areas can be sampled even when use of wound swabs is not possible.

A portal to validated websites on cosmetic surgery: the design of an archetype.

There has recently been an increase in the usage of the Internet as a source of patient information. It is very difficult for laypersons to establish the accuracy and validity of these medical websites. Although many website assessment tools exist, most of these are not practical.A combination of consumer- and clinician-based website assessment tools was applied to 200 websites on cosmetic surgery. The top-scoring websites were used as links from a portal website that was designed using Microsoft Macromedia Suite.Seventy-one (35.5%) websites were excluded. One hundred fifteen websites (89%) failed to reach an acceptable standard.The provision of new websites has proceeded without quality controls. Patients need to be better educated on the limitations of the Internet. This paper suggests an archetypal model, which makes efficient use of existing resources, validates them, and is easily transferable to different health settings.

Psychosocial outcomes derived from an acid burned population in Bangladesh, and comparison with Western norms.

Assault by acid burns typically results in severe disfigurement, yet the psychosocial impact of this injury is so far unreported. This study provides the first empirical data using standardised assessment scales, from 44 acid burns survivors in Bangladesh. Compared with published norms, individuals show high levels of psychological distress including social anxiety and avoidance, anxiety and depression. Consistent with the published literature, there is no relationship between severity of injury and level of psychological distress. One interesting feature of this population is the relative preservation of perceived self-concept, and this is discussed with relation to the supportive and therapeutic environment of the clinic where this group were studied. We also note an interesting sub-group who were attacked by members of their own family and for whom psychological morbidity seems particularly pronounced.

A low temperature method of isolating normal human articular chondrocytes.

OBJECTIVE: Numerous methods for isolation of human chondrocytes are reported in the literature, most based on isolation from animal cartilage. Normal human articular cartilage (NHAC) poses particular problems for isolating chondrocytes when compared to animal or other types of human cartilage: a hardy matrix, combined with few and friable chondrocytes makes isolation difficult. Our objective was to develop an efficient method of isolating chondrocytes from NHAC without jeopardising the viability of these cells. DESIGN: In this study we demonstrate that lowering the enzymatic digestion temperature to 27 degrees C increases cell yield and chondrocyte viability. We then optimised this low temperature isolation of chondrocytes from NHAC by comparing the relative efficacies of trypsin and protease and hyaluronidase in combination with different types of collagenase (I, II and XI) at releasing chondrocytes from their surrounding cartilaginous matrix. Enzymes were tested at different concentrations and for differing times. Outcome measures included determining the amount of cartilage digested, the number of viable chondrocytes isolated per gram of cartilage and cell adherence rates. CONCLUSIONS: From these set of experiments, the method that maximised cell yield without jeopardising cell viability proved to be a two stage process: pre-digestion step using trypsin for 15 min; followed by overnight digestion with a combination of two types of collagenase (types I and II) and at a lower temperature of 27 degrees C. This has resulted in an efficient and robust method of releasing chondrocytes from cartilage, without jeopardising the viability of these cells.

Facial transplantation: adding to the reconstructive options after severe facial injury and disease.

The ability to reconstruct complex facial injuries is still a considerable challenge despite the development of microsurgical techniques. The reconstructive options for conditions such as panfacial burns are severely limited. The result after multiple surgical procedures in this group is often poor in terms of function and cosmesis. Facial transplantation provides a potential solution, but opinion is currently divided about the extent to which the potential benefits to the quality of life can be justified when weighed against the technical, psychological and immunological risks. This paper reviews the current status of the debate and argues that a rigorous research strategy is the only logical basis for countering the ethical objections to a procedure that offers considerable benefits over existing reconstructive options.