Background: Simulation has gained notable recognition for its role as an effective training and assessment modality in the present era of competency-based medical education. Despite the well-documented efficacy of both live and cadaveric animal models, several ethical, financial, and accessibility issues persist with their use. Lower fidelity nonbiological simulators have gained recognition for their ability to circumvent these challenges. This systematic review reports on all prosthetic and virtual reality simulators in use for microsurgery training, with an emphasis on each model’s complexity, characteristics, advantages, disadvantages, and validation measures taken. Methods: A systematic search was performed using the National Library of Medicine (PubMed), MEDLINE, and Embase databases. Search terms were those pertaining to prosthetic and virtual reality models with relevance to microsurgical training in plastic surgery. Three independent reviewers evaluated all articles retrieved based on strict inclusion and exclusion criteria. Results: Fifty-seven articles met the inclusion criteria for review, reporting on 20 basic prosthetic models, 20 intermediate models, 13 advanced models, and six virtual reality simulators. Conclusions: A comprehensive summary has been compiled of all nonbiological simulators in use for microsurgery training in plastic surgery, demonstrating efficacy for the acquisition and retention of microsurgical skills. Metrics-based validation efforts, however, were often lacking in the literature. As plastic surgery programs continue to innovate, ensure accountability, and safely meet today’s training standards, prosthetic simulators are set to play a larger role in the development of a standardized, ethical, accessible, and objectively measurable microsurgery training curriculum for the modern-day plastic and reconstructive surgery resident.

Key Points• Heme oxygenase-1 levels increase during erythroid differentiation.• Heme oxygenase-1 actively participates in maintaining appropriate hemoglobinization rates.Heme is essential for the function of all aerobic cells. However, it can be toxic when it occurs in a non-protein-bound form; cells maintain a fine balance between heme synthesis and catabolism. The only physiological mechanism of heme degradation is by heme oxygenases (HOs). The heme-inducible isoform, HO-1, has been extensively studied in numerous nonerythroid cells, but virtually nothing is known about the expression and potential significance of HO-1 in developing red blood cells. We have demonstrated that HO-1 is present in erythroid cells and that its expression is upregulated during erythroid differentiation. Overexpression of HO-1 in erythroid cells impairs hemoglobin synthesis, whereas HO-1 absence enhances hemoglobinization in cultured erythroid cells. Based on these results, we conclude that HO-1 controls the regulatory heme pool at appropriate levels for any given stage of erythroid differentiation. In summary, our study brings to light the importance of HO-1 expression for erythroid development and expands our knowledge about the fine regulation of hemoglobin synthesis in erythroid cells. Our results indicate that HO-1 plays an important role as a coregulator of the erythroid differentiation process. Moreover, HO-1 expression must be tightly regulated during red blood cell development. (Blood.

Background Rhinoplasty is a complex procedure that requires meticulous planning and precise execution. Plastic surgeons involved in teaching residents must balance a trainee’s hands-on experience while ensuring appropriate execution of difficult maneuvers. Surgical simulation, a field of growing importance with the shift towards competency-based education, may aid in trainee skill development. Through the concept of deliberate practice, the authors looked to explore the utility and economics of 3-dimensional (3D) printing technology to develop a step-specific rhinoplasty simulator. Objectives The main objective of this study was to address rhinoplasty skills previously identified as “learning areas of weakness” and develop a low-cost, step-specific simulator to help rhinoplasty teaching. Methods A patient’s facial bones, upper and lower lateral cartilages, and septum were segmented from a computed tomography scan and rendered in 3D format. This was 3D printed utilizing Ultimaker Polylactic filament with a polyvinyl acetate dissolvable support for bone, a mixture of Rigur 450 and Tango plus polyjet material for cartilage, and Smooth-On Dragon Skin for skin. Results A modular simulator was developed with 3 separate, interchangeable components with a perfect fit design. The simulator allowed for deliberate practice of the 5 rhinoplasty learning areas of weakness, with a maximal recurring cost of $75 CAD. Conclusions Through the employment of 3D printing, a low-cost, maneuver-specific rhinoplasty simulator reinforcing deliberate practice was developed. This concept of simulation-based deliberate practice may be of increasing interest when considering the implementation of competency-based curricular standards in plastic surgery education.

No abstract

Purpose It is not clear whether type of surgical approach affects the amount of blood loss in one-stage bilateral total hip arthroplasty (THA). This study therefore aims to examine if type of surgical approach can affect peri-operative blood loss and allogeneic blood transfusion in patients undergoing one-stage bilateral THA. Methods Records of 319 patients who underwent one-stage bilateral THA from January 2004 to June 2011 were retrospectively reviewed. Patients were divided into two groups: direct anterior (DA) approach (75 patients) and direct lateral (DL) approach (244 patients). Blood loss was calculated using a previously validated formula. Blood loss and need for allogeneic blood transfusion were compared between the two groups. Additionally, the effects of using cell saver and surgical approach were evaluated in a multivariate analysis. Results Compared to the DL approach, calculated blood loss was significantly lower in the DA group (2,813.90±804.13 ml vs 3,617.03±1,148.47 ml) and a significantly lower per cent of patients needed allogeneic blood transfusion in the DA group (26.6 vs 52.4 %). Intra-operative cell saver was used in 36 patients. Compared to the non-cell saver group, mean blood loss was significantly higher in the cell saver group (4,061.0± 1,285.55 ml vs 3,347.71±1,083.85 ml), whereas the difference between the two groups regarding allogeneic blood transfusion was not statistically significant. The DA approach was an independent predictor of lower peri-operative blood loss and allogeneic blood transfusion while using cell saver was not.Conclusions Our results may be explained by the lower extent of muscular dissection performed in the DA approach. Our findings also indicate that intra-operative cell salvage might not be justified in bilateral THA performed expeditiously.

No abstract

rogressive hemifacial atrophy, or Parry-Romberg syndrome, is a rare disorder characterized by gradual, unilateral atrophy of soft tissue in the face within regions innervated by branches of the trigeminal nerve. 1 One widely used classification system, attributed to Iñigo et al., 2 denotes the disease as mild if atrophy is limited to one trigeminal nerve branch, or moderate if it involves two branches. Severe cases are either those involving all three trigeminal nerve branches, or if there exists any bony involvement. 2,3 Degeneration may persist over the course of 2 to 20 years, until spontaneous quiescence, with an earlier age of onset associated with more severe bony involvement and poorer outcomes, especially in pediatric patients. [4][5][6][7] Although treatment with agents such as steroids, methotrexate, antimalarials, and retinoids may be initiated early on during the disease process in an attempt to curb progression, 8 softtissue reconstruction is often necessary for restoration of form and function. 4,9 Although there exists a

De Quervain stenosing tenosynovitis is characterized by swelling and thickening of the extensor retinaculum covering the first dorsal compartment, through which the abductor pollicis longus and extensor pollicis brevis tendons pass. [1][2][3] There exist notable variations in first dorsal compartment anatomy as described according to the Hiranuma classification. 4,5 Presenting patients report pain, swelling, and discomfort over the