[3D-printing in trauma surgery : Planning, printing and processing]. / 3D-Druck in der Unfallchirurgie : Planung, Druck und Aufbereitung.

Possible use of 3D-printing technology in orthopedic surgery ranges from preoperative planning to dedicated counselling with patients by the use of individual 3D models, intraoperative surgery tools or implants and various other applications. This article describes a technique for the creation of intraoperative tools with which the process from computed tomography (CT) images to 3D-printed tools in trauma surgery can safely be administered. For segmentation of CT images a range of different software options is available. The standard triangulation file created in this way (file ending: .stl) must subsequently be post-processed. By the use of the digital casts from bone and fractures in computer-aided design (CAD) programs implants and patient individual tools are created, which can range from ortheses to protheses to intraoperative saw guides.

[Current concepts and new developments of 3D printing in trauma surgery]. / Aktueller Stand und neue Entwicklungen des 3D-Drucks in der Unfallchirurgie.

The use of 3D printing (synonyms "rapid prototyping" and "additive manufacturing") has played an increasing role in the industry for many years and finds more and more interest and application in musculoskeletal surgery, especially orthopedic trauma surgery.In this article the current literature is systematically reviewed, presented and evaluated in a condensed and comprehensive way according to anatomical (upper and lower extremities) and functional aspects. As many of the publications analyzed were feasibility studies, the degree of evidence is low and methodological weaknesses are obvious and numerous; however, this pioneering work is extremely stimulating and important for further development because the technical, medical and economic potential of this technology is huge and interesting for all those involved in the treatment of musculoskeletal problems.

[3D-printed template-assisted reduction of long bone fractures]. / 3D-Druck-Template-gestützte Reposition von Frakturen der langen Röhrenknochen.

INTRODUCTION: In multiply injured patients, the time period between the initial treatment with external fixators (damage control) and the definitive treatment can last from days to weeks. A poor reduction result with the fixator (e.g. malposition in axis, length and rotation) and a long delay from trauma to definitive osteosynthesis are associated with longer operation times, higher intraoperative radiation doses, higher infection rates and an increased likelihood for the necessity to perform an open reduction. MATERIAL AND METHODS: In the described technique computed tomography (CT) is performed after temporary stabilization of the long bone fracture by an external fixator. On the basis of a three-dimensional dataset the fracture can be virtually reduced and a patient-specific reduction fixator can be designed and printed. The 3D printed reduction fixator fits only in the reduced position of the fracture, thus maintaining anatomical bone alignment. The procedure was used for the first time in the Trauma Surgery Clinic of the Medical University Hanover in May 2018 in a polytraumatized female patient with severe brain injury and an open floating knee injury. RESULTS: The procedure could be performed for femoral and tibial shaft fractures. The postoperative CT showed a satisfactory reconstruction of length, torsion and frontal and sagittal plane alignment. Fracture healing was uneventful within 3 months. CONCLUSION: Severely injured patients who initially receive stabilization according to the damage control principle and subsequently remain in the intensive care unit, could particularly benefit from the described postoperative reduction technique. In addition, the reduction fixator can be helpful for the definitive treatment of patients with bilateral fractures of long bones, where a reference to a healthy side is not possible.

Comparison of lipidocolloid and chlorhexidine-impregnated tulle gras dressings following microscopically controlled surgery.

OBJECTIVE: Modified microscopically controlled surgery (MCS) is a staged and margin-controlled excision; after MCS, the selection of an appropriate initial wound dressing plays an important role in wound healing. A wide range of dressings is available for temporary wound coverage; however, data comparing different types of wound dressings after MCS are lacking. The aim of this study was to compare two commonly used and commercially available types of wound dressings. METHOD: We assessed pain levels, wound adherence, bleeding upon dressing removal and signs of infection, with chlorhexidine-impregnated tulle gras and a lipidocolloid dressing used for primary wound dressing following MCS. RESULTS: A total of 42 patients were included. Adherence of the dressing to the wound (p<0.001) and bleeding after removal (p=0.001) were significantly higher in the chlorhexidine-impregnated tulle gras dressing group. Pain during removal of wound dressing had a higher visual analogue scale score (1.9 ± 2.2) in the chlorhexidine-impregnated tulle gras dressing group compared to 0.7 ± 1.0 in the lipidocolloid dressing group (p=0.022). CONCLUSION: The results indicate that the lipidocolloid dressing, when compared with the chlorhexidine-impregnated tulle gras dressing, offers a significant benefit during removal in terms of less pain, less wound adherence and less wound bleeding. DECLARATION OF INTEREST: The authors have no conflict of interest to declare.

Cardiotoxicity associated with trastuzumab (Herceptin) therapy in the treatment of metastatic breast cancer.

Trastuzumab (Herceptin) is a humanised monoclonal antibody that specifically targets HER2-positive breast cancer cells. Safety data collected from pivotal trials with trastuzumab indicate that this therapy is generally well tolerated. However trials of the combination of trastuzumab plus chemotherapy, and in particular chemotherapy with anthracyclines, have revealed an elevated incidence of cardiotoxicity in some patients, which was not apparent in preclinical or early clinical studies. Analyses of the available data suggest that in most cases the cardiotoxicity observed may reflect an exacerbation of anthracycline-induced cardiotoxicity. The biological mechanism of the cardiotoxicity has been investigated in several studies, and current data indicate that the heregulin/HER2-signalling pathway may have an important role. It is of note that the cardiotoxicity is generally reversible and can usually be managed with standard medical treatment. Improvement in cardiac function is seen both in patients who continue trastuzumab and in those in whom further therapy is withdrawn, indicating that with careful management anticancer therapy can be continued.

Retrospective analysis of the safety of Herceptin immunotherapy in metastatic breast cancer.

Approximately 25,000 patients have been treated to date with the humanized anti-HER2 monoclonal antibody, Herceptin. This therapy has proved effective and well tolerated in patients with HER2-positive metastatic breast cancer; adverse events were generally infusion-related fever and chills of mild-to-moderate severity. Cardiotoxicity and infusion-related reactions emerged as the two main safety concerns with the use of Herceptin. Retrospective analysis revealed a higher incidence of heart failure when Herceptin was combined with anthracyclines than that expected with anthracyclines alone. Age, anthracycline exposure and cardiac risk factors were found to be predictors of cardiac adverse events. Patients experiencing cardiac dysfunction responded well to standard cardiac medication and the majority improved. Cardiac function should be monitored regularly and Herceptin should be discontinued if significant heart failure develops unless the benefits for an individual patient outweigh the risks. Of 25,000 patients, 74 (0.3%) were reported to have experienced a serious infusion-related reaction. The majority occurred during or shortly after the first infusion and were characterized by respiratory symptoms. Most patients were successfully treated; a total of 33 patients continued Herceptin therapy with no recurrence of infusion reactions. Although the benefit to risk ratio of Herceptin remains favorable, physicians must be vigilant and aggressive in managing cardiotoxicity and infusion-related reactions.

[Severe mechanical hemolysis after incomplete ductus arteriosus closure: implantation of a second Rashkind occluder]. / Schwere mechanische Hämolyse nach inkomplettem Duktusverschluss: Implantation eines zweiten Rashkind-Okkluders.

A 72 year-old female patient with a persistent ductus arteriosus suffered from a severe mechanical hemolysis after incomplete PDA closure with a Rashkind occluder. The residual shunt was closed with a second occluder 2 days later. Hemolysis was stopped immediately; complete closure of the duct was confirmed by color Doppler 6 weeks and 6 months later.