Step-Specific Simulation: The Utility of 3D Printing for the Fabrication of a Low-Cost, Learning Needs-Based Rhinoplasty Simulator.

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.

Heme oxygenase 1 is expressed in murine erythroid cells where it controls the level of regulatory heme.

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.

Surgical care improvement project (SCIP): has its mission succeeded?

The purpose of this study was to determine if adherence to the surgical care improvement project (SCIP) measures could further reduce rate of surgical site infection (SSI) and venous thromboembolism (VTE) in total joint arthroplasty (TJA) patients. We retrospectively identified all patients who underwent primary or revision TJA at our institution between July 2000 and June 2009. After implementation of SCIP measures, rate of superficial SSI increased (0.42% versus 0.60%, P=0.05) while rate of deep SSI decreased from 0.92% to 0.82% (P=0.46). The rate of DVT was 0.92% before and 0.83% after implementation of SCIP (P=0.51); however, rate of PE increased from 0.87% to 1.30% (P=0.002). Our findings indicated that SCIP has not been successful in reducing complications in TJA patients.

Does the surgical approach in one stage bilateral total hip arthroplasty affect blood loss?

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.

A Comparative Cost Analysis of Local Anesthesia versus Brachial Plexus Block for Complex Hand Surgery.

BACKGROUND: Local anesthesia has shown to be safe and cost-effective for elective hand surgery procedures performed outside of the operating room. The economic benefits of local anesthesia compared to regional anesthesia for hand surgeries performed in the operating room involving repair of tendons, nerves, arteries, or bones are unclear. This study aimed to compare costs pertinent to hand surgeries performed in the main operating room under local anesthesia (LA) or brachial plexus (BP) block. METHODS: We performed a cross-sectional study on the first 70 randomized patients from a prospective controlled trial of anesthesia modalities for hand surgery. The primary objective was to determine the mean anesthesia-related cost, and the secondary objectives were to analyze block performance time, block onset time, duration of anesthesia, duration of surgery, and time in the recovery room. RESULTS: The mean anesthesia-related cost of performing hand surgery under LA as a wrist and/or digital block was $236 ± 30, compared to $435 ± 43 for BP, a difference of $199 per case. The mean block performance time was shorter for LA (1.3 minutes) versus BP (7.0 minutes). The mean anesthesia-related time was longer in BP (30.7 ± 16 minutes) compared to LA (17.7 ± 6.7 minutes), and consequently the total anesthesia time was longer in BP. CONCLUSIONS: We demonstrated that local anesthesia compared to brachial plexus block achieved substantial cost savings in complex hand surgeries by decreasing major expenses. In an era of cost-consciousness, the use of LA represents an important modality for health systems to optimize patient flow and increase cost-effectiveness.

Patient-Reported Quality of Recovery after Local Anesthesia versus Brachial Plexus Block in Hand Surgery: A Randomized Controlled Study.

BACKGROUND: Both local anesthesia (LA) and brachial plexus (BP) anesthesia are commonly used in hand surgery. LA has increased efficiency and reduced costs, but BP is often favored for more complex hand surgery, despite requiring greater time and resources. The primary objective of this study was to assess the quality of recovery of patients who received LA or BP block for hand surgery. Secondary objectives were to compare postoperative pain and opioid use. METHODS: This randomized, controlled, noninferiority study enrolled patients undergoing surgery distal to the carpal bones. Patients were randomized to either LA (wrist or digital block) or BP block (infraclavicular block) before surgery. Patients completed the Quality of Recovery-15 questionnaire on postoperative day (POD) 1. Pain level was assessed with a numeric pain rating scale, and narcotic consumption was recorded on POD1 and POD3. RESULTS: A total of 76 patients completed the study (LA, n = 46, BP, n = 30). No statistically significant difference was found for median Quality of Recovery-15 score between LA [127.5 (interquartile range, 28)] and BP block [123.5 (interquartile range, 31)]. The inferiority margin of LA to BP block at the 95% confidence interval was less than the minimal clinically important difference of 8, demonstrating noninferiority of LA compared with BP block. There was no statistically significant difference between LA and BP block for numeric pain rating scale scores or narcotic consumption on POD1 and POD3 ( P > 0.05). CONCLUSION: LA is noninferior to BP block for hand surgery with regard to patient-reported quality of recovery, postoperative pain, and narcotic use. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.

Utility of Ultrasonography and Significance of Surgical Anatomy in the Management of de Quervain Disease: A Systematic Review and Meta-Analysis.

BACKGROUND: The role of ultrasound in plastic surgery practice has grown significantly over the past decade, with notable applications for conditions of the upper extremity. Its utility for the management of de Quervain disease, however, remains to be established, and the prevalence of first dorsal compartment anatomical variations needs to be adequately assessed. METHODS: A systematic review was performed to evaluate the role of ultrasound in the diagnosis, anatomical characterization, and clinical management of de Quervain disease. A meta-analysis was conducted to establish the prevalence of first dorsal compartment anatomical variations in the de Quervain disease and general population, along with the diagnostic accuracy of ultrasound for their detection. Outcomes were documented and compared to alternative treatment options. RESULTS: Extensor retinaculum thickening, tendon sheath swelling, peritendinous edema, and tendon enlargement were the most common sonographic features of de Quervain disease. The prevalence of an intercompartmental septum in the de Quervain disease surgical population was shown to be significantly greater than in the general cadaveric population (67 percent versus 35 percent, respectively). Although the efficacy of energy-based therapeutic ultrasound remains elusive, ultrasound-guided corticosteroid injections were shown to be more accurate than manual injections (90 to 100 percent versus 40 to 100 percent), and to confer significantly better treatment outcomes (73 to 100 percent versus 59 to 83 percent success rates, respectively). CONCLUSIONS: Ultrasound use is essential to achieve the best evidence-based outcomes in the management of de Quervain disease. The varied prevalence of first dorsal compartment anatomical variations and high accuracy of ultrasound for their detection carry significant prognostic implications.

Soft-Tissue Reconstruction in Progressive Hemifacial Atrophy: Current Evidence and Future Directions.

BACKGROUND: Progressive hemifacial atrophy is a rare disorder characterized by gradual unilateral soft-tissue atrophy in the face, which may also include clinically significant degeneration of underlying muscle and bone. In recent years, there has been a growing body of evidence regarding different soft-tissue reconstructive strategies in progressive hemifacial atrophy and the impact of intervention timing on disease progression. This article provides a comprehensive synthesis of the latest evidence to guide optimal management. METHODS: A comprehensive multidatabase search was performed through April of 2020 using relevant search terms to identify clinical studies. Outcomes, complications, and disease- and patient-related indications pertaining to different soft-tissue reconstructive strategies in progressive hemifacial atrophy were collected and critically appraised. RESULTS: Thirty-five articles reporting on a total of 824 progressive hemifacial atrophy patients were evaluated; 503 patients (61 percent) were managed by microvascular free flaps, 302 patients (37 percent) were managed by autologous fat grafts, and 19 patients (2 percent) were managed by pedicled flaps. A detailed synthesis of outcomes is presented in this article, as is a comparative evaluation of different microvascular free flap options. CONCLUSIONS: Soft-tissue reconstruction in progressive hemifacial atrophy remains an evolving field. Operative decision-making is often multifaceted, and guided by specific volumetric, aesthetic, and functional deficiencies. Serial fat grafting is the primary modality used for patients with mild soft-tissue atrophy, whereas microvascular free flaps widely remain the treatment of choice for reconstruction of large-volume defects. There exists a growing role of graft supplementation to improve fat graft survival, whereas recent evidence demonstrates that early intervention may help curb disease progression.

SMaRT Assessment Tool: An Innovative Approach for Objective Assessment of Flap Designs.

SUMMARY: The teaching and assessment of ideal surgical markings for local flaps required for optimal aesthetic and functional outcomes remain a challenge in the present era of competency-based surgical education. The authors utilized the bilobed flap for nasal reconstruction as a proof of concept for the development of an innovative objective assessment tool based on statistical shape analysis, with a focus on providing automated, evidence-based, objective, specific, and practical feedback to the learner. The proposed tool is based on Procrustes statistical shape analysis, previously used for the assessment of facial asymmetry in plastic surgery. For performance boundary testing, a series of optimal and suboptimal designs generated in deliberate violation of the established ideals of optimal bilobed flap design were evaluated, and a four-component feedback score of Scale, Mismatch, Rotation, and Translation (SMaRT) was generated. The SMaRT assessment tool demonstrated the capacity to proportionally score a spectrum of designs (n = 36) ranging from subtle to significant variations of optimal, with excellent computational and clinically reasonable performance boundaries. In terms of shape mismatch, changes in SMaRT score also correlated with intended violations in designs away from the ideal flap design. This innovative educational approach could aid in incorporating objective feedback in simulation-based platforms in order to facilitate deliberate practice in flap design, with the potential for adoption in other fields of plastic surgery to automate assessment processes.

Arthroscopic anterior cruciate ligament reconstruction with modified "wireless" cross-screw transfix femoral fixation.

Among several graft fixation options in arthroscopic ACL reconstruction for hamstring tendons, transcondylar fixation has been suggested to offer mechanical advantages compared to other femoral fixation systems. Blind nature of the procedure may result in several complications including iliotibial band irritation syndrome, breakage of the bio absorbable cross-pin, stress fracture of the femoral cortex, and more commonly intraoperative wire loop twisting, resulting in fixation failure, wire breakage or graft laceration. We used "wireless" transfixation technique to avoid complications associated with wire loop.

A modification of tibial inlay fixation in posterior cruciate ligament reconstruction by interference screw: a biomedical study on calf tibial bone model.

This study presents a modification of tibial inlay technique in posterior cruciate ligament (PCL) reconstruction and evaluates the structural properties of tibial side fixation of the graft, comparing tibial inlay technique and a new modification, that is interference screw fixation of tibial side of the graft in suggested supine position which is more applicable, with less potential intraoperative neurovascular complications. Forty fresh calf knees that were prepared from 20 healthy 3 years old calves which were between 200 and 220 kg were the subject of this study. The tibias were separately used simulating tibial side PCL reconstruction with tibial tuberosity-patellar tendon-patellar bone graft. Tibial side of the graft was fixed using two cancellous screws in 20 tibiae and with interference screw in obliquely oriented canal in another 20 tibiae. Load-to-failure test was carried out on ten samples from each group. The remaining samples were used for cycling loading. Mann-Whitney U test was used to compare structural properties of each group. No significant differences were observed between two methods at load-to-failure test; but mean elongation at 1,000 cycles of new modification was significantly lower than tibial inlay technique.

Nonbiological Microsurgery Simulators in Plastic Surgery Training: A Systematic Review.

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.

A moderate-intensity static magnetic field enhances repair of cartilage damage in rabbits.

BACKGROUND AND AIMS: Electromagnetic fields have been proposed to enhance healing of cartilage defects by stimulation of chondrocyte proliferation, proteoglycan synthesis as well as decreasing pain and improving motion in osteoarthritic patients. However, the effects of a moderate-intensity static magnetic field on cartilage repair have not been investigated. This study tries to determine the effects of a moderate-intensity permanent magnetic field of 40 mT on cartilage repair. METHODS: Defects of 3 mm in diameter and 6 mm in depth were made on the weight bearing surface of the right medial femoral condyle of 30 rabbits. The animals were divided randomly into three equal groups (magnet, sham and control). In the magnet group, cylindrical permanent magnets were implanted subcutaneously medial to the medial femoral condyle, while in the sham group the cylindrical ceramic were not magnetized, and nothing was implanted in controls. After 12 weeks of observation, Mankin's microscopic scoring was done on all specimens, and irregularity of surface characteristics, cell colonization, hypocellularity, cartilage matrix formation, and presence of empty lacunae were investigated. RESULTS: Each of these characteristics showed significant differences in magnet group relative to control and sham groups (p <0.05). Mankin's score was 1.6 ± 0.6 in magnet group, 7.2 ± 1.6 in sham group and 7.7 ± 1 in control group (p <0.001). CONCLUSIONS: [corrected] In this animal study, microscopic Mankin's scoring depicted histological improvement in cartilage of magnet group.