Three-Dimensional Printing in Surgical Education: An Updated Systematic Review of the Literature.

INTRODUCTION: Three-dimensional printing (3DP) is being integrated into surgical practice at a significant pace, from preprocedural planning to procedure simulation. 3DP is especially useful in surgical education, where printed models are highly accurate and customizable. The aim of this study was to evaluate how 3DP is being integrated most recently into surgical residency training. METHODS: We performed a structured literature search of the OVID/MEDLINE, EMBASE, and PUBMED databases following the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Articles published from 2016 to 2023 that met predefined inclusion and exclusion criteria were included. Data extracted included surgical subspecialty using 3DP, application of 3DP, and any reported satisfaction measures of trainees. A thorough analysis of pooled data was performed to evaluate satisfaction rates among studies. RESULTS: A total of 85 studies were included. The median number of participants was 18 (interquartile range 10-27). Fourteen surgical disciplines were represented, with ear, nose, and throat/otolaryngology having the highest recorded utilization of 3DP models among residents and medical students (22.0%), followed by neurosurgery (14.0%) and urology (12.0%). 3DP models were created most frequently to model soft tissue (35.3%), bone (24.7%), vessel (14.1%), mixed (16.4%), or whole organs (6.66%) (Fig.1). Feedback from trainees was overwhelmingly positive regarding the fidelity of the models and their support for integration into their training programs. Among trainees, the combined satisfaction rate with their use in the curriculum was 95% (95% confidence interval, 0.92-0.97), and the satisfaction rate with the model fidelity was 90% (95% confidence interval, 0.86-0.94). CONCLUSIONS: There is wide variation in the surgical specialties utilizing 3DP models in training. These models are effective in increasing trainee comfort with both common and rare scenarios and are associated with a high degree of resident support and satisfaction. Plastic surgery programs may benefit from the integration of this technology, potentially strengthening future surgical curricula. Objective evaluations of their pedagogic effects on residents are areas of future research.

The value of microvascular breast reconstruction: Cost equivalence of TRAM and DIEP flaps implications in the era of CMS reforms.

BACKGROUND: Recent CMS billing changes have raised concerns about insurance coverage for deep inferior epigastric perforator (DIEP) flap breast reconstruction. This study compared the costs and utilization of transverse rectus abdominis myocutaneous (TRAM), DIEP, and latissimus dorsi (LD) flaps in breast reconstruction. METHOD: The study utilized the National Inpatient Sample database to identify female patients who underwent DIEP, TRAM, and LD flap procedures from 2016 to 2019. Key data such as patient demographics, length of stay, complications, and costs (adjusted to 2021 USD) were analyzed, focusing on differences across the flap types. RESULTS: A total of 17,770 weighted patient encounters were identified, with the median age being 51. The majority underwent DIEP flaps (73.5%), followed by TRAM (14.2%) and LD (12.1%) flaps. The findings revealed that DIEP and TRAM flaps had a similar length of stay (LOS), while LD flaps typically had a shorter LOS. The total hospital charges to costs using cost-to-charge ratio were also comparable between DIEP and TRAM flaps, whereas LD flaps were significantly less expensive. Factors such as income quartile, primary payer of hospitalization, and geographic region significantly influenced flap choice. CONCLUSION: The study's results appear to contradict the prevailing notion that TRAM flaps are more cost-effective than DIEP flaps. The total hospital charges to costs using cost-to-charge ratio and hospital stays associated with TRAM and DIEP flaps were found to be similar. These findings suggest that changes in the insurance landscape, which may limit the use of DIEP flaps, could undermine patient autonomy while not necessarily reducing healthcare costs. Such policy shifts could favor less costly options like the LD flap, potentially altering the landscape of microvascular breast reconstruction.

The Impact of Metabolic Syndrome on Postoperative Outcomes in Abdominal Body Contouring: A Propensity Score-Matched Nationwide Analysis.

BACKGROUND: Metabolic syndrome (MetS) represents cardiometabolic dysregulation, defined by hypertension, obesity, diabetes, and dyslipidemia. There remains a significant gap in our understanding of whether MetS impacts outcomes of abdominal body contouring procedures. We aimed to assess the influence of MetS on postoperative outcomes of abdominal body contouring by concurrent abdominoplasty and panniculectomy. METHODS: The ACS-NSQIP database was utilized to identify patients who underwent concurrent abdominoplasty and panniculectomy procedures from 2012 to 2022. Through propensity score matching, distinct cohorts were established based on the presence of MetS, characterized by patients receiving medical interventions for diabetes mellitus and hypertension, with a body mass index exceeding 30 kg/m2. Univariate and multivariate analyses were conducted to evaluate differences between groups. RESULTS: A total of 14,642 patients underwent abdominal body contouring from 2012 to 2022. Following propensity score matching, 730 patients were included in the analysis, with 365 in each group (MetS vs. non-MetS). Bivariate analysis revealed a longer hospital length of stay (2.3 vs. 1.6 days; p = 0.007) in the MetS cohort compared to the non-MetS cohort. Patients diagnosed with MetS had an average length of stay of 0.6 days longer than non-MetS patients (95% CI [0.17, 1.01]; p = 0.007). No noteworthy disparities were observed in the rates of 30-day wound complications, mild systemic, and severe systemic complications, and readmission rates between the groups. CONCLUSIONS: Our findings suggest that abdominal body contouring remains a secure option for patients with MetS. Nonetheless, the longer hospital length stays observed in patients with MetS may translate to increased overall costs to the healthcare system. Continued research is warranted to comprehensively assess the economic implications of MetS in the context of abdominal body contouring. LEVEL OF EVIDENCE III: 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 .

From Case Reports to Molecular Insight: Examining the Outcomes and Underlying Mechanisms of Squamous Cell Carcinoma in Breast Implant Patients-A Systematic Review.

There is extensive coverage in the existing literature on implant-associated lymphomas like anaplastic large-cell lymphoma, but breast implant-associated squamous cell carcinoma (BIA-SCC) has received limited scholarly attention since its first case in 1992. Thus, this study aims to conduct a qualitative synthesis focused on the underexplored association between breast implants and BIA-SCC. A systematic review was conducted utilizing the PubMed, Web of Science, and Cochrane databases to identify all currently reported cases of BIA-SCC. Additionally, a literature review was performed to identify potential biochemical mechanisms that could lead to BIA-SCC. Studies were vetted for quality using the NIH quality assessment tool. From an initial pool of 246 papers, 11 met the quality criteria for inclusion, examining a total of 14 patients aged between 40 and 81 years. BIA-SCC was found in a diverse range of implants, including those with smooth and textured surfaces, as well as those filled with saline and silicone. The condition notably manifested a proclivity for aggressive clinical progression, as evidenced by a mortality rate approximating 21.4% within a post-diagnostic interval of six months. Our literature review reveals that chronic inflammation, driven by various external factors such as pathogens and implants, can initiate carcinogenesis through epigenetic modifications and immune system alterations. This includes effects from exosomes and macrophage polarization, showcasing potential pathways for the pathogenesis of BIA-SCC. The study highlights the pressing need for further investigation into BIA-SCC, a subject hitherto inadequately addressed in the academic sphere. This necessitates the urgency for early screening and intervention to improve postoperative outcomes. While the review is confined by its reliance on case reports and series, it serves as a valuable reference for future research endeavors.

12-Year Trends of Orofacial Clefts in the United States: Highlighting Racial/Ethnic Differences in Prevalence of Cleft Lip and Cleft Palate.

OBJECTIVE: Discrepancies in prevalence among infants with orofacial clefts are public health research priorities. Our objective was to calculate updated estimated prevalence of orofacial clefts in the United States, with sub-analyses by racial/ethnic group. DESIGN: The National Birth Defect Prevention Network database was used to evaluate trends in cases with orofacial cleft in the United States from 2006 to 2018. Cases with cleft lip with and without cleft palate (CL ± P) and cleft palate (CP) alone were sub-stratified by racial/ethnic category. Estimated prevalence was calculated using the total live births reported in each maternal racial/ethnic group. The odds ratio (OR) was calculated to measure the strength of association between racial/ethnic group and risk of orofacial clefts. RESULTS: Estimated prevalence rates show that maternally-reported Native American/Alaskan Native individuals were 43.8% (p < 0.0001) and 36.0% (p < 0.0001) more likely to have CL ± P and CP alone, respectively, compared to maternally-reported non-Hispanic White individuals. Estimated prevalence of CL ± P in maternally-reported non-Hispanic Black individuals (OR = 0.64) and maternally-reported Asians/Pacific Islander individuals were significantly lower than in maternally-reported non-Hispanic White individuals (OR = 0.63, p < 0.0001). Estimated prevalence of CP alone was significantly lower in maternally-reported non-Hispanic Black individuals (OR = 0.64, p < 0.0001), maternally-reported Asians/Pacific Islander individuals (OR = 0.69, p < 0.0001), and maternally-reported Hispanic individuals (OR = 0.81, p < 0.0001). CONCLUSIONS: Across the total population, there was no significant change in estimated orofacial cleft prevalence. However, there were significant disproportions in estimated orofacial cleft prevalence across racial/ethnic groups, which may guide further discussion among craniofacial health care providers and centers and their patients regarding differences in cleft risk factors.

Evaluating skin colour diversity in the validation of scar assessment tools.

Across scar studies, there is a lack of dark-skinned individuals, who have a predisposition for keloid formation, altered pigmentation and poorer quality of life (QOL). There is a need for patients of colour to be included in scar scale development and validation. In this study, we evaluate the racial diversity of patients included in the validation of scar assessment scales. A systematic review was conducted for articles reporting on the validation of a scar assessment tool. Racial, ethnic and Fitzpatrick skin type (FST) data were extracted. Fifteen scar scale validation studies were included. Nine of the studies did not mention FST, race or ethnicity of the patients. Two of the studies that reported FST or race information only included White patients or included no FST V/VI patients: mapping assessment of scars (MAPS) and University of North Carolina '4P'. Only four studies included non-White patients or dark-skinned patients in the validation of their scar scale: the modified Vancouver Scar Scale (VSS), modified Patient and Observer Scar Assessment Scale (POSAS), acne QOL and SCAR-Q scales. The patients included in the modified VSS validation were 7% and 13% FST V/VI, 14% African in the modified POSAS and 4.5% FST V/VI in the SCAR-Q. We highlight the severe lack of diversity in scar scale validation, with only 4 out of 15 studies including dark-skinned patients. Given the susceptibility of darker-skinned individuals to have poorer scarring outcomes, it is critical to include patients of colour in the very assessment tools that determine their scar prognosis. Inclusion of patients of colour in scar scale development will improve scar assessment and clinical decision-making.

Long-term outcomes of open midline ventral hernia repair using a narrow well-fixed retrorectus polypropylene mesh.

INTRODUCTION: The ultimate measure of successful abdominal wall reconstruction is a pain-free, complication-free, and durable hernia repair. Open techniques have generally lost favor, but they still have much to offer for patients with skin deficits and excess. The long-term complication rates for open hernia repairs is unknown. Electronic medical records now provide the ability to easily follow patients who have switched medical institutions. Using this tool, we followed a cohort of abdominal wall reconstruction patients who had an early high "success" rate. METHODS: We performed a retrospective chart review of 101 patients who underwent open ventral hernia repair with a narrow well-fixed retrorectus uncoated polypropylene mesh by a single surgeon (GAD) between the years of 2010 and 2015. These patients were initially reported in a 2016 publication. Patients' post-operative follow-up by any medical provider assessing the abdominal region were studied up until August 2023. Patient demographics, operative reports, and postoperative course were re-reviewed. RESULTS: A total of 101 patients underwent ventral hernia repair. Mean follow-up time was 7.68 years (range 1.8 - 13.0 years). There were no recurrent hernias across the studied time period and no instances of enterocutaneous fistulas. 15 patients (15%) had abdominal surgery after hernia repair unrelated to their original surgery and 5 patients (5%) reported chronic post-operative pain. 13 patients died in the follow-up period, all unrelated to the abdominal wall surgery. CONCLUSION: Open well-fixed narrow retrorectus mesh hernia repairs perform well in the long-term without fistulas, extrusions, and hernia recurrence.

Management of Superficial and Deep Peroneal Nerve Neuromas with Targeted Muscle Reinnervation in Nonamputees: Operative Technique and Early Outcomes.

Background: Targeted muscle reinnervation (TMR), a surgical technique developed by the senior authors that coapts proximal ends of nerves to distal motor nerves of adjacent muscles, has demonstrated efficacy in the treatment and prevention of neuroma pain. The objective of this study is to describe the surgical technique for TMR of the superficial peroneal nerve (SPN) and deep peroneal nerve (DPN) in nonamputee patients and provide data on postoperative functional outcomes. Methods: A single-institution retrospective chart review was performed between March 2018 and April 2021. Patients were de-identified and included if they were nonamputees receiving TMR for pain in the peroneal nerve distribution. Data extracted included demographic information, symptoms before operation, relevant nerve coaptation, peri-, and postoperative complications, and long-term functional outcomes. Results: Of the 19 patients reviewed, 11 patients underwent TMR of the SPN alone: eight had complete resolution of their symptoms; two indicated partial improvement in pain; and one patient had no improvement. Four patients underwent TMR of the DPN alone: two patients had complete resolution of their pain, and two patients had partial improvement with pain. Four patients underwent TMR of both the SPN/DPN: two patients had complete resolution of their symptoms, and two patients were noted to have significant improvement but had persistent pain from prior foot operations. Average follow-up time was 260 days. Conclusions: TMR is a successful technique in the management of SPN and DPN neuroma pain. Our technique revealed excellent clinical outcomes, no procedure-specific complications, and improved subjective pain reports.

Evaluating the Mechanical Strength of Three Dimensionally (3D) Printed Implants in Septorhinoplasty through Finite Element Analysis (FEA).

BACKGROUND: Autologous nasoseptal cartilage grafts are used to correct nasal asymmetry and deviation in rhinoplasty, but patients who have undergone multiple surgeries may have limited autologous cartilage tissue available. 3D-printed L-strut implants may address these challenges in the future, but their mechanical strength is understudied. Silk fibroin-gelatin (SFG), polycaprolactone (PCL), and polylactide (PLA) are bio-inks known for their strength. We present Finite Element Analysis (FEA) models comparing the mechanical strength of 3D-printed SFG, PCL, and PLA implants with nasoseptal cartilage grafts when autologous or allografts are not available. METHODS: FEA models compared the stress and deformation responses of 3D-printed solid and scaffold implant replacements to cartilage. To simulate a daily force from overlying soft tissue, a unidirectional load was applied at the "keystone" region given its structural role and compared with native cartilaginous properties. RESULTS: 3D-printed solid SFG, PCL, and PLA and scaffold PCL and PLA models demonstrated lower deformations compared to cartilage. Solid SFG balanced strength and flexibility. The maximum stress was below all materials' yield stresses suggesting their deformations are unlikely permanent under a daily load. CONCLUSIONS: Our FEA models suggest that 3D-printed L-strut implants carry promising mechanical strength. Solid SFG's results mimicked cartilage's mechanical behavior. Thus, scaffold SFG merits further geometric optimization for potential use for cartilage substitution. 3D-printed septal cartilage replacement implants can potentially enhance surgical management of patients who lack available donor cartilage in select settings. CLINICAL RELEVANCE STATEMENT: Computational simulations can evaluate 3D-printed implant strength and their potential to replace septal cartilage in septorhinoplasty.

Breast Implant Silicones and B Cell-Mediated Immune Responses: A Systematic Review of Literature.

Introduction: Breast implants are under recent scrutiny owing to concerns about their potential for inducing immunological diseases, namely breast implant-associated anaplastic large cell lymphoma and breast implant illness. However, the impact of silicone on biologic systems remains unclear. Therefore, we performed a systematic literature review to evaluate the information available on silicone breast implants and their effect on one arm of the adaptive immune response-B lymphocytes and antibody formation. Methods: We conducted a systematic review in EMBASE/PUBMED in accordance with the PRISMA guidelines, with search entry terms requiring discussion of silicone and immunity. The initial review returned 1079 citations. Manual screening was performed to include studies that were specific to the humoral response after exposure to silicone. Secondary full text review was performed. The extracted data included animal models and findings pertinent to B cells/antibodies in response to breast implant silicones. Results: In total, 39 studies on B cells/antibodies and breast-implant-associated silicones were identified. Among them, 23 studies were in humans, 14 in animal models, and 2 were in vitro. Common themes included identification of antisilicone antibodies in women with breast implants, anticollagen antibodies, presence of activated B cells or immunoglobulin G in implant capsules, and sensitization of lymphocytes to silicone in vitro. Conclusion: Despite controversial findings in the literature, there is evidence that silicone breast implants activate B cells in the breast implant capsule and may have systemic effects on the production of autoantibodies and/or sensitization of B lymphocytes to silicone. Further research is needed on how breast implants impact other arms of the immune system to understand their long-term biological impact.

Redefining Surgical Materials: Applications of Silk Fibroin in Osteofixation and Fracture Repair.

Silk and silk derivatives have emerged as a possible alternative in surgical device development, offering mechanical strength, biocompatibility, and environmental sustainability. Through a systematic review following PRISMA guidelines, this study evaluated silk fibroin's application across pre-clinical and clinical settings, focusing on its role as screws and plates for osteofixation. A comprehensive search yielded 245 studies, with 33 subjected to full-text review and 15 ultimately included for qualitative analysis. The findings underscore silk fibroin's superior properties, including its tunable degradation rates and ability to be functionalized with therapeutic agents. In vivo and in vitro studies demonstrated its efficacy in enhancing bone healing, offering improved outcomes in osteofixation, particularly for craniofacial defects. Silk fibroin's remarkable attributes in biodegradation and drug release capabilities underscore its potential to enhance patient care. Ultimately, silk fibroin's integration into surgical practices promises a revolution in patient outcomes and environmental sustainability. Its versatility, coupled with the continuous progress in fabrication techniques, signals a promising horizon for its widespread acceptance in the medical field, potentially establishing a new benchmark in surgical treatment. Further research is expected to solidify the transition of silk products from basic science to patient care, paving the way for widespread use in various surgical applications.

Comparing Collagenase and Tissue Subcision for Cellulite Treatment of the Buttock and Thigh Regions: A Systematic Review and Meta-analysis.

Background: In this systematic review, we assessed the therapeutic efficacy and safety of Clostridium histolyticum collagenase (CCH) and tissue subcision (TS) for treating cellulite, which ranges from subtle to pronounced lesions. Methods: A systematic review was performed following PRISMA guidelines for CCH and TS treatment to the thigh and gluteal regions. A proportion meta-analysis was then conducted using Stata statistical software. Results: A total of 14 studies were incorporated into the final analysis. Nine focused on TS and five on CCH injection, collectively reporting outcomes for 1254 patients. Of these, 465 received CCH injection and 789 underwent subcision. For bruising, rates were 89% [95% confidence interval (CI), 71%-96%] with CCH injection and 99% (95% CI, 85%-99%) for subcision; pain requiring analgesic was reported at 74% (95% CI, 55%-87%) for CCH and 60% (95% CI, 43%-76%) for subcision; both showed induration at 7% (95% CI, 5%-11% for CCH, 95% CI, 2%-25% for subcision), whereas skin discoloration was higher post-CCH injection at 16% (95% CI, 10%-26%) compared with 7% (95% CI, 5%-10%) postsubcision. Conclusions: Both CCH and TS seem effective treatments for cellulite. However, upon evaluating the adverse outcomes between the two modalities, subcision demonstrated a higher incidence of bruising, albeit similar rates of induration compared with CCH injection. Conversely, the CCH injection group manifested a higher propensity for pain requiring analgesia and notably exhibited increased instances of skin discoloration compared with their subcision patient group. Further standardized research is crucial for more informed cellulite treatment decisions and for comparing efficacy, safety, and cost-effectiveness between TS and CCH.

Dorsal Preservation versus Component Dorsal Hump Reduction Rhinoplasty: An Assessment of Patient-reported Outcomes.

Background: The literature on patient-reported outcomes (PROs) discussing dorsal preservation rhinoplasty (DPR) and component dorsal hump reduction (CDHR) is scarce. This study aims to fill the gap in PROs between these techniques. Methods: A systematic review was conducted to investigate PROs of DPR and CDHR. A proportion meta-analysis was conducted using Stata statistical software. Results: A total of 25 studies met our inclusion criteria, pooling 1706 participants, with 13 studies on CDHP and 12 studies on DPR. Overall satisfaction rates were high, varying from 84% to 100% across studies. A subgroup analysis revealed that both techniques exhibited equally high satisfaction with no statistical differences (P = 0.18). A random-effects model revealed that about two of 100 treated patients underwent revisions across our cohort (95% interquartile range: 0-4). Notably, the CDHR technique was associated with a significant 53.7-point reduction in the Standardized Cosmesis and Health Nasal Outcomes Survey (SCHNOS)-cosmetic domain [95% confidence interval (CI): -62.7 to -44.8, P < 0.001], along with a meaningful improvement in SCHNOS-obstructive scores by -27.3 points (95% CI: -50.5 to -4.04, P = 0.02). Conversely, the DPR was linked to a 55.3-point reduction in the SCHNOS-cosmetic domain (95% CI: -60.7 to -49.9, P < 0.001), and a -19.5 point change in the SCHNOS-obstructive domain (95% CI: -27.9 to -11.1, P < 0.001). Conclusion: Although PROs are comparable, the literature suggests that CDHR outcomes may be better than DPR in alleviating obstructive symptoms, potentially offering an evidence-based choice for addressing functional concerns in rhinoplasty.

Utilization of patient-reported outcome measures in plastic surgery clinical trials: A systematic review.

BACKGROUND: Patient-reported outcomes (PROs) have evolved to validated questionnaires assessing health-related quality of life. This systematic review evaluates the utilization of PROs in United States plastic and reconstructive surgery (PRS) clinical trials (CTs). METHODS: A medical librarian conducted a search strategy for PRS CTs from 2012 to 2022. CTs were identified and assessed for PRO utilization. Summary statistics were performed, and Fisher's exact test was used for subgroup analysis. RESULTS: Of the 3609 studies initially identified, 154 were PRS CTs. Approximately half (80 studies) employed PROs, encompassing 13,190 participants, 95% (12,229) of whom were female. Among the CTs, 37 (48%) were in the field of reconstruction, while 25 (32%) were cosmetic. Pain (35%) and patient satisfaction (24%) were the most common primary outcomes. Validated PROs were the main outcome in 61% of these trials, with the visual analog scale (19%) and BREAST-Q (15%) as the top instruments. Funding was primarily private (34%) or not reported (49%). No significant trend in validated PRO usage was observed over the examined decade. CONCLUSIONS: The use of PROs is relevant for healthcare delivery and improvement as they provide insight into the efficacy of treatments from a patient-centered viewpoint. PROs are reported in just over half of PRS CTs, and within those CTs, the use of validated questionnaires is inconsistent. Therefore, emerging CTs should strive to incorporate PRO measures and utilize the existing validated tools to assess novel interventions and ensure that the data reported is objective.