Use of a collagen-elastin matrix with split-thickness skin graft for defect coverage in complex wounds.

OBJECTIVE: Severe soft tissue damage with destruction of the dermis requires plastic reconstructive treatment. For multimorbid patients or patients unable to undergo major reconstructive surgery, use of dermal substitutes, such as a collagen-elastin matrix (CEM) with a split-thickness skin graft (STSG), instead of local or free flap surgery, may be a valid and easy treatment option. We aimed to investigate and compare the outcomes and rate of successful defect reconstruction using CEM plus STSG, using either a one-step approach (simultaneous CEM and STSG) or a two-step approach (CEM and negative wound pressure therapy (NPWT), with secondary STSG transplantation). METHOD: A single-centre, retrospective follow-up study of patients who had received CEM was conducted. Wounds had been treated with an STSG transplantation covering a CEM (MatriDerm, MedSkin Solutions Dr. Suwelack AG, Germany). Previous attempts at wound closure with conventional methods had failed in the selected patient population, which would usually have resulted in flap surgery. RESULTS: Overall, 46 patients were included (mean age 60.9±20.0 years), with a total of 49 wound sites. We analysed 38 patients with wounds that did not require flap coverage; 18 patients received the one-step approach and 20 patients received the two-step approach. The mean follow-up in these patients was 22±11.5 months, and one patient was lost to follow-up. Overall, 29 (78.4%) wounds remained closed. Wounds which did not successfully heal were related to comorbidities, such as diabetes, alcohol misuse and smoking. Using the one-step approach, long-term defect coverage was achieved in 13 (76.5%) wounds and 16 (80.0%) wounds were closed using the two-step approach. However, there was no statistically significant differences between the one- or two-step approaches regarding the rate of development of a wound healing disorder. CONCLUSION: Wound closure was achieved in 38 complex wounds using CEM plus STSG, while 11 wounds needed secondary flap coverage. In the flap-free wounds, there were no statistically significant differences between the one-step versus two-step approach. Using a simple defect reconstruction algorithm, we successfully used CEM plus STSG to treat complex wounds.

Evaluation of the ankle function after Achilles tendon resection: a retrospective clinical study.

INTRODUCTION: The Achilles tendon is the strongest tendon in the human body and has the function of plantar ankle flexion. When the tendon is exposed, the peritendineum has been breached and the thick avascular tendon colonized with bacteria, a complete resection of the tendon may be indicated to achieve infection control and facilitate wound closure. The Achilles tendon reconstruction is not mandatory, as the plantar flexion of the ankle joint is assumed by the remaining flexor hallucis longus, flexor digitorum longus and tibialis posterior muscles. Our study aimed to evaluate the impact of Achilles tendon resection without reconstruction on leg function and quality of life. MATERIAL AND METHODS: We retrospectively evaluated all patients who were treated with an Achilles tendon resection between January 2017 and June 2022 in our quaternary institution. After evaluating the data, the patients who survived and were not amputated were contacted for re-evaluation, which included isokinetic strength measurement of both ankle joints, evaluation of the ankle range of motion and collection of several functional scores. RESULTS: Thirty patients were included in the retrospective study, with a mean age of 70.3 years, including 11 women and 19 men. The most frequent cause of the infection was leg ulcer (43.3%), followed by open tendon suture (23.3%). No tendon reconstruction was performed. Fifteen patients could be gained for reevaluation. The average difference in ankle flexion torque on the injured side compared to the healthy side at 30 degrees/second was 57.49% (p = 0.003) and at 120 degrees/second was 53.13% (p = 0.050) while the difference in power was 45.77% (p = 0.025) at 30 degrees/second and 38.08% (p = 0.423) at 120 degrees/second. The follow-up time was between 4 and 49 months and a positive correlation could be determined between the time elapsed from surgery and the ankle joint strength. There was a significant loss of range of motion on the operated side compared to the healthy side: 37.30% for plantar flexion, 24.56% for dorsal extension, 27.79% for pronation and 24.99% for supination. The average Lepillhati Score was 68.33, while the average American Orthopedic Foot and Ankle Score was 74.53. CONCLUSION: The complete Achilles tendon resection leaves the patient with satisfactory leg function and an almost normal gait. Especially in elderly, multimorbid patients, straightforward tendon resection and wound closure provide fast infection control with acceptable long-term results. Further prospective studies should compare the ankle function and gait in patients with and without Achilles tendon reconstruction after complete resection.

Microbiological study of sternal osteomyelitis after median thoracotomy - a retrospective cohort study.

INTRODUCTION: Deep sternal wound infection is a rare but feared complication of median thoracotomies and is usually caused by microorganisms from the patient's skin or mucous membranes, the external environment, or iatrogenic procedures. The most common involved pathogens are Staphylococcus aureus, Staphylococcus epidermidis and gram-negative bacteria. We aimed to evaluate the microbiological spectrum of deep sternal wound infections in our institution and to establish diagnostic and treatment algorithms. METHODS: We retrospectively evaluated the patients with deep sternal wound infections at our institution between March 2018 and December 2021. The inclusion criteria were the presence of deep sternal wound infection and complete sternal osteomyelitis. Eighty-seven patients could be included in the study. All patients received a radical sternectomy, with complete microbiological and histopathological analysis. RESULTS: In 20 patients (23%) the infection was caused by S. epidermidis, in 17 patients (19.54%) by S. aureus, in 3 patients (3.45%) by Enterococcus spp., in 14 patients (16.09%) by gram-negative bacteria, while in 14 patients (16.09%) no pathogen could be identified. In 19 patients (21,84%) the infection was polymicrobial. Two patients had a superimposed Candida spp. INFECTION: Methicillin-resistant S. epidermidis was found in 25 cases (28,74%), while methicillin-resistant S. aureus was isolated in only three cases (3,45%). The average hospital stay for monomicrobial infections was 29.93 ± 13.69 days and for polymicrobial infections was 37.47 ± 19.18 (p = 0.03). Wound swabs and tissue biopsies were routinely harvested for microbiological examination. The increasing number of biopsies was associated with the isolation of a pathogen (4.24 ± 2.22 vs. 2.18 ± 1.6, p < 0,001). Likewise, the increasing number of wound swabs was also associated with the isolation of a pathogen (4.22 ± 3.34 vs. 2.40 ± 1.45, p = 0.011). The median duration of antibiotic treatment was 24.62 (4-90) days intravenous and 23.54 (4-70) days orally. The length of antibiotic treatment for monomicrobial infections was 22.68 ± 14.27 days intravenous and 44.75 ± 25.87 days in total and for polymicrobial infections was 31.65 ± 22.29 days intravenous (p = 0.05) and 61.29 ± 41.45 in total (p = 0.07). The antibiotic treatment duration in patients with methicillin-resistant Staphylococci as well as in patients who developed an infection relapse was not significantly longer. CONCLUSION: S. epidermidis and S. aureus remain the main pathogen in deep sternal wound infections. The number of wound swabs and tissue biopsies correlates with accurate pathogen isolation. With radical surgical treatment, the role of prolonged antibiotic treatment remains unclear and should be evaluated in future prospective randomized studies.

Pathological study of sternal osteomyelitis after median thoracotomy-a prospective cohort study.

PURPOSE: Osteomyelitis of the sternum may arise either as a primary condition or secondary to median thoracotomy after cardiac surgery, with the latter being decidedly more frequent. Deep sternal wound infections appear as a complication of median thoracotomy in 0.2 to 4.4% of cases and may encompass the infection of the sternal bone. To date, there are no exhaustive histopathological studies of the sternal osteomyelitis. METHODS: Our work group developed a surgical technique to remove the complete infected sternal bone in deep sternal wound infections. We therefore prospectively examined the en bloc resected sternal specimens. Seven standard histological sections were made from the two hemisternums. RESULTS: Forty-seven sternums could be investigated. The median age of the patients in the cohort was 66 (45-81) years and there were 10 females and 37 males. Two methods were developed to examine the histological findings, with one model dividing the results in inflammatory and non-inflammatory, while the second method using a score from 0 to 5 to describe more precisely the intensity of the bone inflammation. The results showed the presence of inflammation in 76.6 to 93.6% of the specimens, depending on the section. The left manubrial sections were more prone to inflammation, especially when the left mammary artery was harvested. No further risk factors proved to have a statistical significance. CONCLUSION: Our study proved that the deep sternal wound infection may cause a ubiquitous inflammation of the sternal bone. The harvest of the left mammary artery may worsen the extent and intensity of infection.

Lower leg reconstruction after resection of a squamous cell carcinoma on necrobiosis lipoidica with a pedicled fibula and an extended anterolateral thigh flap-a case report.

BACKGROUND: Extensive loss of soft tissue and bone due to neoplasia, trauma, or infection in extremities often leads to amputation. CASE PRESENTATION: We present the case of a 72-year-old female patient presenting with an extended cutaneous squamous cell carcinoma of the lower leg, developed on top of necrobiosis lipoidica. After achieving the R0 resection, a 26 × 20-cm soft tissue and 15-cm tibial bone defect resulted. The contralateral leg had been lost due to the same disease 18 years before. We achieved a successful reconstruction of the leg using a pedicled fibula transplantation, an extended anterolateral thigh perforator flap, and an internal fixation with plate and screws. Two years after the original surgery, the patient is relapse-free and mobile, with adequate function of the reconstructed foot. CONCLUSIONS: Our case presented a unique combination of pedicled fibula transplantation and free extended ALT perforator flap to reconstruct an extensive defect after resection of a rare cSCC on top of NL. In selected cases, the boundaries of limb salvage can be pushed far beyond the current standards of treatment.

Thumb reconstruction after radical tumor resection using free osteocutaneous lateral arm flap with secondary humerus fracture-a case report.

INTRODUCTION: Malignant diseases with infiltration of bony structures in the area of the phalanges or metacarpals require either amputation or complex reconstruction. The decision for reconstruction means to restore length, mobility, sensibility, stability as well as aesthetics. METHODS: We present a case of complex first ray reconstruction of the left hand using a free osteocutaneous lateral arm flap from the ipsilateral side. The reconstruction was performed after radical resection of an exulcerated squamous cell carcinoma, including the first metacarpal bone, trapezium, partial trapezoid and distal scaphoid as well as partial resection of the extensor pollicis longus, extensor pollicis brevis, abductor pollicis longus and flexor carpi radialis tendons. The osteosynthetic restoration was achieved distally by a double wire cerclage and a proximally by temporary K-wire suspension. Moreover, to reconstruct the extensor pollicis longus tendon the ipsilateral palmaris longus tendon was harvested and used. Postoperatively, a secondary humerus fracture occurred, which was initially attended by plate osteosynthesis. The fracture showed delayed healing, which was treated by re-plating and autologous cancellous bone. RESULTS: 12 months postoperatively, the patient showed an excellent outcome with length preservation and good range of motion, sensibility, stability and aesthetic of the thumb. Furthermore, the quarterly tumor aftercare showed no evidence of recurrence. CONCLUSION: This case report showed that the free osteocutaneous lateral arm flap is a reliable solution for the reconstruction of the first ray with a great functional and aesthetic outcome. To prevent a secondary humerus fracture, a preventive plate osteosynthesis simultaneous with the osteocutaneous flap elevation should be considered.

Topical negative pressure wound therapy enhances the local tissue perfusion - A pilot study.

BACKGROUND: Topical negative pressure wound therapy (TNPWT) is a regularly used method in modern wound treatment with a growing and diverse potential for clinical use. So far positive effects on microcirculation have been observed and examined, although precise statements on the underlying mechanism appear unsatisfying. OBJECTIVE: The aim of our study was to extend the understanding of the effect of TNPWT on tissue perfusion and determine the time frame and the extent to which the tissue perfusion changes due to TNPWT. MATERIAL AND METHODS: TNPWT was applied to the anterior thighs of 40 healthy individuals for 30 min, respectively. Before and up to 90 min after the application, measurements of the amount of regional haemoglobin (rHb), capillary venous oxygen saturation (sO2), blood flow (flow) and velocity were conducted with spectrophotometry (combining white light spectrometry and laser Doppler spectroscopy) within two different depths/skin layers. A superficial measuring probe for depths up to 3 mm and a deep measuring probe for up to 7 mm were used. RESULTS: All parameters show significant changes after the intervention compared to baseline measurements. The greater effect was seen superficially. The superficially measured rHb, sO2 and flow showed a significant increase and stayed above the baseline at the end of the protocol. Whereas deeply measured, the rHb initially showed a decrease. The flow and sO2 showed a significant increase up to 60 min after the intervention. CONCLUSION: The application of TNPWT on healthy tissue shows an increase in capillary-venous oxygen saturation and haemoglobin concentration of at least 90 min after intervention. A possible use in clinical practice for preconditioning to enhance wound healing for high-risk patients to develop wound healing disorder, requires further studies to investigate the actual duration of the effect.

AV loop free flap: an interdisciplinary approach for perineal and sacral defect reconstruction after radical oncological exenteration and radiation in a colorectal cancer patient.

BACKGROUND: The free flap transfer of a latissimus dorsi flap (LDF) for the closure of sacral wound defects after pelvic exenteration and radiation therapy offers a successful tool of the plastic surgeon. This case report shows the successful coverage using an upstream arterio-venous (AV) loop in combination with an LDF. CASE PRESENTATION: We describe the case of a patient who underwent a pelvic exenteration and radiation therapy due to a local recurrence of rectal cancer. The initially used VRAM flap could not ensure a satisfactorily wound closure. An interdisciplinary approach first yielded an AV loop using both greater saphenous veins and was connected to the arteria and vena femoris followed by a free LDF transfer, which was performed 11 days later. The result was an excellent reconstructive and plastic coverage of the sacral wound defect with a well-perfused LDF. The long-term result showed a perfectly integrated flap in the sacral region. CONCLUSION: We recommend the free LDF for the coverage of large wound defects in irradiated areas after the failure of VRAM flap. If an AV loop is necessary within the flap transfer, we recommend conducting two procedures to guarantee the perfusion of the AV loop.

Penile reconstruction with dermal template and vacuum therapy in severe skin and soft tissue defects caused by Fournier's gangrene and hidradenitis suppurativa.

The aim of this article is to improve the treatment of patients with complete skin loss of the penile shaft after Fournier's gangrene or hidradenitis suppurativa using modern biomatrices and topical negative pressure therapy. From January 2010 to December 2011, three patients with Fournier's gangrene or hidradenitis suppurativa were treated. After initial radical debridements, topical negative pressure therapy was applied for wound stabilisation. After that dermal templates (acellular dermal matrix) were used to achieve early healing and topical negative pressure-dressing in a special setting or a special foam compression bandage was used together with a urinary catheter. After integration of the dermal template, a split-thickness skin graft is used for coverage and again secured with a circular total negative pressure-dressing. In all cases, the split-thickness skin grafts healed very well applying this therapy concept. The patients were very satisfied with the functional as well as with the aesthetic outcome. We suggest a new method of staged reconstruction to successfully preserve the functionality of the penis after complete loss of the skin and soft tissue of the penile shaft using modern biomatrices and topical negative pressure therapy.

Ischaemia-related cell damage in extracorporeal preserved tissue - new findings with a novel perfusion model.

Tissue undergoing free transfer in transplant or reconstructive surgery always is at high risk of ischaemia-related cell damage. This study aims at assessing different procedures using an extracorporeal perfusion and oxygenation system to investigate the expression of hypoxia inducible factor (HIF)-1-α as marker for hypoxia and of the pro-apoptotic protein Caspase-3 in skeletal muscle to elucidate potential improvements in tissue conservation. Twenty-four porcine rectus abdominis muscles were assigned to five different groups and examined after they had been extracorporeally preserved for 60 min. time. Group I was left untreated (control), group II was perfused with a cardioplegic solution, group III was flushed with 10 ml of a cardioplegic solution and then left untreated. Group IV and V were perfused and oxygenated with either an isotone crystalloid solution or a cardioplegic solution. Among others, immunohistochemistry (Caspase-3 and HIF-1-α) of muscle samples was performed. Furthermore, oxygen partial pressure in the perfusate at the arterial and venous branch was measured. Expression of Caspase-3 after 60 min. was reduced in all groups compared to the control group. Furthermore, all groups (except group III) expressed less HIF-1-α than the control group. Oxygenation leads to higher oxygen levels at the venous branch compared to groups without oxygenation. Using an extracorporeal perfusion and oxygenation system cell damage could be reduced as indicated by stabilized expressions of Caspase-3 and HIF-1-α for 60 min. of tissue preservation. Complete depletion of oxygen at the venous branch can be prevented by oxygenation of the perfusate with ambient air.

A histopathologic and immunohistochemical study on liquification of human adipose tissue ex vivo.

BACKGROUND: This preliminary ex vivo study aimed to clarify the pathophysiologic mechanisms of fat tissue depletion by subcutaneous drug application. Therefore, the lipolytic effects of phosphatidylcholine plus deoxycholate (Lipostabil) (L) and of deoxycholate (DC) alone were compared with those of sodium chloride (NaCl) and hydrogen peroxide (H2O2) as control agents. The study enrolled 10 patients receiving abdominoplasty. The treatment periods for each sample and solution were 1, 3, 5, and 7 h. The samples were analyzed morphologically using hematoxylin-eosin (H&E) staining and also immunohistochemically using Caspase 3 and tumor necrosis factor (TNF)-alpha. Morphologic changes were seen best after 5 h of application time. Except for NaCl, all the samples in the H&E staining showed marked damage of adipocyte cell membranes, with the greatest disruption of normal cell architecture after hydrogen peroxide (H2O2) application. Immunohistochemistry using TNF-alpha showed positive results for the deoxycholate and Lipostabil samples and highly positive results for the H2O2 sample. Data from this study indicate that Lipostabil and deoxycholate induce pathways of cell necrosis involving TNF-alpha. These short-term experiments indicate that Lipostabil affects fat tissue in the way of a chemical-toxic destruction rather than via a physiologically induced, programmed cell death.

Accuracy of Three-dimensional Scan Technology and Its Possible Function in the Field of Hand Surgery.

Background: Three-dimensional (3D) technology has become a standard manufacturing element in many industries and has gained significant interest in plastic surgery. The 3D scans are widely used for patient communication, virtual surgery planning, and intraoperative tool manufacturing, providing a more comprehensive view of procedures and their outcomes compared with 2D visualization. Methods: We evaluated the performance of six commercially available 3D scanners by acquiring 3D models of a human hand and a 3D-printed replica of a human hand. We performed objective comparisons between the 3D models of the replica using color mapping techniques. Moreover, we compared the results of the human hand 3D scans. Results: We achieved the highest precision with the Artec Space Spider 3D scanner (Artec 3D) when scanning the 3D-printed replica. The SD was ±0.05 mm, and the scan did not have major defects that needed manual correction. On the human hand scan, we achieved the best results using the Artec Eva (Artec 3D), the resulting scan was an accurate digital representation of the scanned human hand. Conclusions: In our study, the Artec Space Spider 3D scanner demonstrated superior precision when scanning a 3D-printed replica, deviating only slightly from the original data, making it an optimal choice for nonmoving objects such as casts or medical instruments. For scanning human hands, the Artec Eva 3D scanner exhibited the highest performance, offering accuracy comparable to the Artec Space Spider, but with the added benefit of being able to scan larger objects.

Dimensional Accuracy in 3D Printed Medical Models: A Follow-Up Study on SLA and SLS Technology.

Background: With the rise of new 3D printers, assessing accuracy is crucial for obtaining the best results in patient care. Previous studies have shown that the highest accuracy is achieved with SLS printing technology; however, SLA printing technology has made significant improvements in recent years. Methods: In this study, a realistic anatomical model of a mandible and skull, a cutting guide for mandibular osteotomy, and a splint for orthognathic surgery were replicated five times each using two different 3D printing technologies: SLA and SLS. Results: The SLA group had a median trueness RMS value of 0.148 mm and a precision RMS value of 0.117 mm. The SLS group had a median trueness RMS value of 0.144 mm and a precision RMS value of 0.096 mm. There was no statistically significant difference in RMS values between SLS and SLA technologies regarding trueness. Regarding precision, however, the RMS values for SLS technology were significantly lower in the splint and cutting guide applications than those printed with SLA technology. Conclusions: Both 3D printing technologies produce modern models and applications with equally high dimensional accuracy. Considering current cost pressures experienced by hospitals, the lower-cost SLA 3D printer is a reliable choice for point-of-care 3D printing.

Scalp reconstruction with locoregional and free flaps - a retrospective cohort study.

Introduction: Scalp defect reconstruction requires interdisciplinary cooperation to restore soft tissue and osseous defects. While wound closure and form restoration, often a short-term treatment goal, ensures patient survival, the long-term preservation of the head and neck's integrity and aesthetics is crucial for maintaining quality of life. This study aims to compare, quantify, and establish a safe and reproducible approach to various reconstruction options and the postoperative complication profile for individual scalp defect areas. Materials and methods: We retrospectively evaluated patients who underwent scalp reconstruction at our institution between March 2017 and April 2022. The inclusion criterion was the presence of a soft tissue defect at the cranium level. Results: We included 31 patients in the study (17 males, 14 females), with an average age of 61 years (range 17-92 years). Eight patients had received radiotherapy in the affected region. The mean defect size was 72.5±116 cm2 (range 20-441 cm2), and an average of 3±2 surgeries had been performed before the plastic surgical treatment was initiated. Eleven patients had only a soft tissue defect, while 20 patients had an associated bone defect. Fifteen of these patients received a cranioplasty. The rotation flap was the most frequently used (n=23), with or without split-thickness skin grafting, followed by the free latissimus dorsi muscle flap with split-thickness skin grafting (n=5), and the free lateral arm flap (n=2). Revision surgeries were necessary in 38.7% of cases due to wound healing disorders (n=9), bleeding (n=2), and cerebrospinal fluid leaks (n=1). Eventually, all wounds were successfully closed. Conclusion: Complex scalp defects can be closed using local flaps, thereby restoring aesthetics and tissue integrity. Free flaps remain a reliable solution for extensive defects. Moreover, in cases requiring cranioplasty, careful preoperative planning and an uncontaminated wound are essential for successful treatment.

[Evidence of modern diagnostic, conservative, and surgical therapy of secondary lymphoedema]. / Evidenz der modernen Diagnostik, der konservativen und chirurgischen Therapie des sekundären Lymphödems.

BACKGROUND: Secondary lymphoedema (SL) is one of the most common and, at the same time, most significant consequences and complications of modern oncological therapy. Although a thorough patient history and physical examination are sufficient to substantiate a suspicion, it is essential to perform functional imaging of the lymphatic system for a targeted diagnosis and determination of severity. For this purpose, techniques such as MR and ICG lymphography as well as ultra-high-frequency ultrasound examinations have been developed and validated in recent years. The selective use of these techniques has allowed for individualized indications and successful stage-dependent treatment using (super)microsurgical techniques to restore regional lymphatic drainage in the context of intensified conservative therapy. METHOD: Systematic review of the literature on the diagnosis and treatment of SL with subsequent analysis and classification of the results into evidence levels according to the Oxford Centre for Evidence-Based Medicine and the GRADE Scale. RESULTS: The established and validated diagnosis of SL includes imaging (ICG fluorescence lymphography, MR lymphography and Tc-99 functional lymphoscintigraphy) in case of a clinical suspicion and in high-risk patients. Complex physical decongestion therapy (CPE) is superior to physical therapy or compression alone. (Super)microsurgery of SL allows for a postoperative reduction in the frequency of CPE, a reduction of erysipelas rates, a volume reduction of the lymphomatous extremity and, if carried out prophylactically, a lower incidence of SL. Suction-assited lipectomy can produce long-term, stable reductions in circumference and an improvement in quality of life. CONCLUSION: Patients with SL benefit from conservative therapy with regular re-evaluation. Patients with a high risk for SL or with clinical deterioration or persistent symptoms under guideline-based conservative therapy can benefit from (super)microsurgical therapy after an individualized functional diagnostic evaluation of the lymphatic system. Excisional dermolipectomies or lympholiposuctions are available and effective for advanced and refractory stages.

The impact of two radical sternectomy surgical techniques on the outcome of deep sternal wound infections.

BACKGROUND: Deep sternal wound infection (DSWI) is a rare, yet devastating complication after cardiac surgery. While the surgical treatment always implies the soft tissue and bone debridement, there is little data about this procedure. The aim of our study was to evaluate the impact of the radical sternectomy on the outcome in patients with DSWI and to identify the risk factors which could influence the result. The surgical techniques of piecemeal sternectomy and the newly developed en bloc sternectomy were also evaluated. METHODS: The study was developed as a retrospective cohort study. 86 patients with DSWI who received a radical sternal resection at our institution between March 2018 and December 2021 were included. RESULTS: The average age of the cohort was 67.3 ± 7.4 years, and 23.3% of patients were female. The average length of stay trended shorter after en bloc sternectomy (median 26 days) compared to piecemeal sternectomy (37 days). There were no significant differences between the piecemeal and en bloc sternal resection techniques. Anticoagulant and antiplatelet drugs had no significant influence on bleeding and transfusion rates. Obese patients showed an increased risk for postoperative bleeding requiring reintervention. Transfusion of packed red blood cells was significantly associated with lower hemoglobin values before surgery and ASA Class 4 compared to ASA Class 3. The in-hospital mortality was 9.3%, with female sex and reintervention for bleeding as significant risk factors. Nine patients developed an infection relapse as a chronic fistula at the level of clavicula or ribs, with ASA Class 4 as a risk factor. CONCLUSION: Radical sternectomy is a safe procedure to treat DSWI with compromised sternal bone. Both piecemeal and en bloc techniques ensure reliable results, while complications and mortality appear to be patient-related.

Evaluation of the Dimensional Accuracy of Robot-Guided Laser Osteotomy in Reconstruction with Patient-Specific Implants-An Accuracy Study of Digital High-Tech Procedures.

Background/Objective: With the rapid advancement in surgical technologies, new workflows for mandibular reconstruction are constantly being evaluated. Cutting guides are extensively employed for defining osteotomy planes but are prone to errors during fabrication and positioning. A virtually defined osteotomy plane and drilling holes in robotic surgery minimize potential sources of error and yield highly accurate outcomes. Methods: Ten mandibular replicas were evaluated after cutting-guided saw osteotomy and robot-guided laser osteotomy following reconstruction with patient-specific implants. The descriptive data analysis summarizes the mean, standard deviation (SD), median, minimum, maximum, and root mean square (RMS) values of the surface comparison for 3D printed models regarding trueness and precision. Results: The saw group had a median trueness RMS value of 2.0 mm (SD ± 1.7) and a precision of 1.6 mm (SD ± 1.4). The laser group had a median trueness RMS value of 1.2 mm (SD ± 1.1) and an equal precision of 1.6 mm (SD ± 1.4). These results indicate that robot-guided laser osteotomies have a comparable accuracy to cutting-guided saw osteotomies, even though there was a lack of statistical significance. Conclusions: Despite the limited sample size, this digital high-tech procedure has been shown to be potentially equivalent to the conventional osteotomy method. Robotic surgery and laser osteotomy offers enormous advantages, as they enable the seamless integration of precise virtual preoperative planning and exact execution in the human body, eliminating the need for surgical guides in the future.

Surgical and Oncologic Outcome following Sacrectomy for Primary Malignant Bone Tumors and Locally Recurrent Rectal Cancer.

INTRODUCTION: Bone sarcoma or direct pelvic carcinoma invasion of the sacrum represent indications for partial or total sacrectomy. The aim was to describe the oncosurgical management and complication profile and to analyze our own outcome results following sacrectomy. METHODS: In a retrospective analysis, 27 patients (n = 8/10/9 sarcoma/chordoma/locally recurrent rectal cancer (LRRC)) were included. There was total sacrectomy in 9 (incl. combined L5 en bloc spondylectomy in 2), partial in 10 and hemisacrectomy in 8 patients. In 12 patients, resection was navigation-assisted. For reconstruction, an omentoplasty, VRAM-flap or spinopelvic fixation was performed in 20, 10 and 13 patients, respectively. RESULTS: With a median follow-up (FU) of 15 months, the FU rate was 93%. R0-resection was seen in 81.5% (no significant difference using navigation), and 81.5% of patients suffered from one or more minor-to-moderate complications (especially wound-healing disorders/infection). The median overall survival was 70 months. Local recurrence occurred in 20%, while 44% developed metastases and five patients died of disease. CONCLUSIONS: Resection of sacral tumors is challenging and associated with a high complication profile. Interdisciplinary cooperation with visceral/vascular and plastic surgery is essential. In chordoma patients, systemic tumor control is favorable compared to LRRC and sarcomas. Navigation offers gain in intraoperative orientation, even if there currently seems to be no oncological benefit. Complete surgical resection offers long-term survival to patients undergoing sacrectomy for a variety of complex diseases.

[The Impact of Industrial Sponsorship on Research Findings in Randomised Clinical Trials in Plastic and Aesthetic Surgery: a Cross- Section Analysis of the Past 12 Years]. / Der Einfluss von Industrie-Sponsoring auf Forschungsergebnisse randomisierter klinischer Studien in der Plastischen und Ästhetischen Chirurgie: Eine Querschnittsanalyse der letzten 12 Jahre.

BACKGROUND: Industry funding of research studies can cause the results in the field of plastic, reconstructive and aesthetic surgery to be biased towards the sponsors. This paper aims to review randomised clinical trials (RCTs) published by leading international journals in plastic, reconstructive and aesthetic surgery with respect to characteristics and possible industry-friendly conclusions in favour of those funding the study. MATERIAL AND METHODS: Characteristic data and funding of RCTs published by leading international plastic surgery journals from January 2010 to January 2022 were evaluated. The studies were categorised based on their thematic focus and the results in light of the existing funding. RESULTS: A total of 381 RCTs were included in the analysis, 68.5% of which were from a university (n=261). The larger proportion of studies did not disclose any information about the research funding. While 26% (n=98) of the studies analysed were funded by companies, 9.7% (n=37) were funded by universities/the government (p<0.05, 95% confidence interval). The overall focus of private clinics was aesthetics (n=32). Generally, the topic aesthetics (n=153) was funded by industry in 28 of 100 cases (28% industry/private sponsors compared with 9% university/government). Regarding reconstruction/burns/hand surgery, 9.2% of studies were funded by companies/private sponsors. Funding for research by university-based institutions was industry-sponsored in 25% (n=64) of cases. Regarding industry-sponsored studies, 73% (n=71) of the results were product-friendly in their conclusion (p<0.05, 95% confidence interval) and placed their thematic focus on therapeutic drug/product application (n=50, 75%). CONCLUSION: In terms of funding, industry and private sponsors take a leading role both in reconstruction and aesthetics. Nonetheless, the majority of the evaluated studies were not financed by the private sector. In cases where the research was funded by private companies, the results were significantly in favour of the product. Aesthetics as a focus is currently more frequently funded by industry than reconstruction, burn, and hand surgery.

[Evidence-based Research in Plastic and Aesthetic Surgery: Cross-sectional Analysis of Research Papers Between 2019 and 2021]. / Evidenzbasierte Forschung in der Plastischen und Ästhetischen Chirurgie: Querschnittsanalyse von Forschungsarbeiten im Zeitraum 2019­2021.

BACKGROUND: In the field of plastic and aesthetic surgery, continuous international publication is seen annually. However, the publication output is not regularly assessed for its level of evidence. In view of the strong publication activity, a regular assessment of the evidence level of the current publication years is reasonable and was the objective of this work. MATERIAL AND METHODS: We evaluated the Journal of Hand Surgery/JHS (European Volume Journal), the journal Plastic and Reconstructive Surgery/PRS and the journal Handchirurgie, Mikrochirurgie und Plastische Chirurige/HaMiPla from January 2019 to December 2021. The authors' affiliation, the type of publication, the number of patients examined and the level of evidence with existing conflicts of interest were considered. RESULTS: A total of 1341 publications were evaluated. Of these, 334 original papers were published in JHS, 896 in PRS, and 111 in HaMiPla. The largest share were retrospective papers (53.5%, n=718). The further distribution was as follows: 18% (n=237) clinical prospective papers, 3.4% (n=47) randomised clinical trials (RCT), 12.5% (n=168) experimental papers and 6.5% (n=88) anatomic studies. The distribution of evidence levels of all studies was as follows: Level I: 1.6% (n=21), Level II: 8.7% (n=116), Level III: 20.3% (n=272), Level IV: 25.2% (n=338), Level V: 2.3% (n=31). In 42% (n=563) of the papers, there was no indication of the level of evidence. Most level I evidence was from university hospitals (n=16) in 76.2% (χ²-test 0.619, >0.05, 95% confidence interval). CONCLUSION: Although RCTs are inappropriate for many surgical questions, well-designed and conducted cohort or case-control studies could improve the evidence base. Many of the current studies tend to be retrospective and do not have a control group. Researchers in the field of plastic surgery should consider using a cohort or case-control design when an RCT is not feasible.