[Success factors and obstacles in the implementation of competence-oriented teaching in surgery]. / Erfolgsfaktoren und Hindernisse bei der Implementierung kompetenzorientierter Lehre in der Chirurgie.

BACKGROUND AND OBJECTIVES: For successful competence-oriented teaching at the medical faculties it is important to identify the factors that influence its implementation in order to benefit from the strengths and balance out weaknesses. The present study examined the success factors and obstacles of the implementation of competence-oriented teaching in the surgical discipline from the point of view of students and lecturers. METHODS: After implementation of competence-oriented teaching based on the teaching goals of the NKLM, in clinical examination courses (bedside teaching and block internship, BP) at two hospitals, a qualitative content analysis and quantification of the answers were performed using focus group interviews and questionnaires with students (S) and lecturers (D). RESULTS: During the summer semester 2022 a total of 31 students and 14 lecturers were interviewed in focus groups and 143 questionnaires (123 S, 20 D) were analyzed. For the students the presence of concrete competences/teaching goals, guidelines for the lesson, transparent goals and ability to demand teaching goals as well as structured lessons and mentoring were the main success factors. Lecturers on the other hand reported the presence of concrete goals, assistance for the lesson preparation and the activity of the students as success factors. The results of the questionnaires showed that the majority (88% S, 75% D) were informed about the teaching goals and considered them to be followed (84%S, 95% D). Obstacles were the factors "time", "mentoring" and "information". Factors that were between negative and positive (indifferent factors) were "uncertainty about competence-orientation" and "uncertainty how to examine the teaching success". DISCUSSION: Transparent structure and teaching goals as well as a mentoring system are the success factors for the implementation of competence-oriented lessons and should be used as strengths. Indifferent factors represent weaknesses and need to be addressed by training and instruction. Restricted time and personnel resources are the immanent problems that hamper the implementation and require fulminant structural changes.

[Changes in age distribution and frequency of comorbidities in patients in the occupational insurance association treatment process]. / Veränderung der Altersstruktur und Häufigkeit von Komorbiditäten bei Patienten im bg-lichen Heilverfahren.

BACKGROUND: Due to the demographic development the proportion of older patients has increased. These show at least a higher rate of comorbidities, which affects the length of inpatient hospital stay. Until now no uniform recording exists for such comorbidities within the occupational insurance association system even if the clinical relevance is beyond dispute. Adaptations within the system with increased interdisciplinary treatment are necessary. OBJECTIVE: The aim of this study was to analyze changes in the age distribution and the frequency of comorbidities in patients in the occupational insurance association system. METHODS: The study was a retrospective analysis of age distribution and comorbidities of all operatively treated occupational insurance association patients in 2005 (n = 631), 2010 (n = 1180) and 2015/2016 (n = 2315). A comparison of the age groups ≤29 years, 30-49 years, 50-65 years and ≥66 years was performed. RESULTS: The proportion of patients aged 50-65 years showed a significant increase: 2005 (26.5%), 2010 (30.5%) and 2015/2016 (37.3%) (p < 0.001) and an increased proportion of patients with at least 1 comorbidity: 2005 (38.7%), 2010 (52.5%) and 2015/2016 (52.9%) (p = 0.01). This was statistically significant (p < 0.001, p = 0.005) within the age group 30-49 years (2005: 31.1%, 2015/2016: 49.0%) and the age group 50-65 years (2005: 55.7%, 2015/2016: 67.1%). Significant changes were found for arterial hypertension, morbid obesity, thyroid and respiratory diseases. In addition, there was an increase in multimorbid patients. DISCUSSION: A changing age distribution with a tendency to an increased number of older patients and an increased frequency of comorbidities could be determined. In the present documentation system of the occupational insurance association treatment procedure these comorbidities are insufficiently recorded and considered, even though their clinical relevance is indisputable. Adaptations with respect to intensified interdisciplinary cooperation are necessary.

[The acetabulum nonunion: reconstruction and reosteosynthesis : A long-term outcome]. / Die Acetabulumpseudarthrose: Rekonstruktion und Reosteosynthese : Ein Langzeitergebnis.

Acetabular nonunions are rare, especially after operative treatment of an acetabular fracture. There are only single reports of the reconstruction and therapy of acetabular nonunion. Furthermore, there are fewer reports for treatment of acetabular nonunion with a long follow-up. We report a successful revision of an acetabular nonunion after transversal fracture and previous operative intervention, as well as the long-term follow-up after revision surgery.

[Air Entrapment Caused by Valve Mechanisms in Chronic Wounds, a Benign Phenomenon? A Series of Three Cases]. / Air Entrapment durch einen Ventilmechanismus bei chronischen Wunden, ein harmloses Phänomen? Eine Beschreibung von 3 Fällen.

BACKGROUND: Benign subcutaneous emphysema caused by a valve mechanism and subsequent air entrapment is rare. Less invasive treatment can be performed, but acute life-threatening infectious diseases should be ruled out before treatment; these include gas gangrene or other infections caused by gas producing bacteria. PATIENTS AND METHODS: We retrospectively report on three patients with chronic wounds who developed benign subcutaneous extremity emphysema caused by valve mechanisms with subsequent air entrapment. Patient 1 had a chronic wound at his stump after a lower leg amputation years ago. Due to weight loading and unloading of the lower leg prosthesis while walking, air was sucked in and triggered subcutaneous emphysema. Patient 2 had a persistent fistula at his lateral thigh due to a chronic osteomyelitis and Girdlestone hip. Caused by the up-and-down movements of the femur during walking air was entrapped and led to emphysema. Patient 3 had a drain in his knee for development of a chronic fistula because of a persistent infection of his knee prosthesis. In extension of the knee, the drain was clamped in and air was entrapped during knee flexion and then seeped into the surrounding subcutaneous tissue. No signs of infection in the blood samples were present in two of the patients. None of the patients had fever and no gas producing bacteria were identified in the microbiological cultures. Only multisensitive Staphylococcus aureus was present in the wounds of patients 1 and 2. RESULTS: Two patients were treated surgically. One patient was treated by fasciotomy plus debridement and irrigation of the wound. A second patient was treated by debridement of the Girdlestone hip, air evacuation and insertion of a drain. No sign of infection - such as necrosis or gangreneous tissue - was seen during these operations. In patient 3, the drain was removed in flexion of the knee and air was removed from the subcutaneous tissue through a separate, sterile needle punction. CONCLUSION: There have been few published reports on benign subcutaneous emphysema caused by a valve mechanism. No standardised treatments exist, as it is initially difficult to distinguish this condition from an acute life-threatening infection. If a patient has a chronic wound at the location of the endoprosthesis or stump prosthesis after amputation, the possibility of benign air entrapment should be routinely considered.

[Trampoline-related injuries in children: an increasing problem]. / Trampolinassoziierte Verletzungen im Kindesalter. Ein zunehmendes Problem.

INTRODUCTION: The sales of recreational trampolines have increased during the past few years. Severe injuries are associated in part with trampoline sport in the domestic setting. Therefore, this study was conducted to confirm the hypothesis of an increase in trampoline-related injuries in conjunction with the increasing sales of recreational trampolines and to find out what kind of injuries are most frequent in this context. METHODS: Between 01/1999 and 09/2013 all trampoline-related injuries of children (0-16 years of age) were assessed retrospectively. Only those cases were evaluated which described with certainty a trampoline-associated trauma. The fractures were considered separately and assigned to specific localisations. Additionally, accidents at home were differentiated from institutional accidents. RESULTS: Within the past 13 years and 9 months trampoline-related injuries were seen in 195 infants. Fractures were present in 83 cases (42 %). The average age was 10 ±â€Š3.4 years (range: 2-16 years). Within first half of the observed time period (7½ years; 01/1999 to 06/2006) 73 cases were detected with a significantly increasing number of injuries up to 122 cases between 07/2006 and 09/2013 (7 years, 3 months), which corresponds to an increase of 67 % (p = 0,028). The vast majority of these injuries happened in the domestic setting (90 %, n = 175), whereas only 10 % (n = 20) of the traumas occurred in public institutions. In 102 children (52 %) the lower extremity was affected and in 51 patients (26 %) the upper extremity was involved (head/spine/pelvis: n = 42, 22 %). The upper extremity was primarily affected by fractures and dislocations (n = 38, 76 %). At the upper extremity there were more injuries requiring surgery in contrast to the lower extremity (n = 11) or cervical spine (n = 1). CONCLUSION: The underlying data show a significant increase of trampoline-related injuries within the past years. The upper extremity is the second most affected after the lower extremity, but is more associated with fractures in contrast to other localisations and had to be operated on the most. Because of the increase of recreational trampolines within past years an increase of trampoline-associated injuries has to be expected in the future. The security guidelines should be followed exactly and the infants should be under supervision.

[Post-traumatic bipolar dislocation of the clavicle: is operative treatment reasonable?]. / Posttraumatische bipolare Luxation der Klavikula : Ist die operative Versorgung sinnvoll?

Bipolar dislocation of the clavicle ("floating clavicle") is extremely rare. It exists no standardised treatment for this trauma and the treatment is often conservative. This is mainly an anterior displacement of the sternoclavicular joint (type III according to Allman) and a posterior dislocation of the acromioclavicular joint (type IV according to Rockwood).We report on a 60 year old male who fell onto the right shoulder. He sustained a 'floating clavicle' and had a massive dislocation, impairment of range of motion and pain. Venous congestion was observable. We stabilised the dislocated acromioclavicular joint with a Balser's plate, the sternoclavicular joint was fixed with PDS cord tension band technique around the first rip and the sternum. In addition we resected the anterior part of the distal clavicle to get a better cosmetic result. Post-operatively the patient had an excellent range of motion without any further symptoms after six weeks and one year. Venous congestion was not more observable.In most of the cases dislocations of both ends of the clavicle are treated conservatively. We recommend an operative treatment especially in young and active patients to avoid re-dislocation and to archive better cosmetic results.

Effects of continuous perfusion on human bone marrow stromal cells seeded on a decellularized bovine Achilles tendon matrix.

Ruptures of tendons and ligaments are a widely common injury in traumatology. The aim of the study was the development of a substitute tissue for such defects by methods of tissue-engineering. Human bone marrow stromal cells (hBMSC) were seeded on a decellularized bovine Achilles tendon and cultivated in a special bioreactor. We examined the influence of continuous perfusion on proliferation and biomechanical stability compared to static cultivation. Samples were taken on day 0, 7 and 14. Decellularized tendons were chosen as a negative control. Cell quantity was measured by the MTS-Test. Histology was analyzed by Haematoxylin-Eosin- and Pentachrome-coulouring. The cultivated tendons were tested biomechanically compared with the decellularized control group. MTS-Test revealed an increase of cell count of 7% in the static group and a decrease of 9% in the perfusion group. The perfusion group showed a stronger network of the fibroblasts and a higher amount of produced extracellular matrix. Biomechanical testing revealed significantly higher stability in the decellularized control group. This trial shows up new possibilities of managing defects of tendons and ligaments. The continuous perfusion in a bioreactor can improve the structure of the matrix seeded with hBMSC.

[Blunt force injuries due to martial arts in children--a diagnostic problem? Delayed diagnosis of an infected hematoma]. / Stumpfe Verletzungen im Kampfsport bei Kindern--ein diagnostisches Problem? Verzögerte Diagnose eines infizierten Hämatoms.

INTRODUCTION: Blunt force injuries in martial arts occur frequently but isolated hematoma of muscles in the extremities is rare. Even minor trauma of the lower extremities due to throwing techniques in judo and other forms of Asian martial arts can lead to major pathologies. METHODS: A 9-year-old girl presented with an unclear swelling and soreness of the calf muscle. The patient could not remember an obvious traumatic event. She was admitted 4 days later because of increased swelling, pain and erythema. The parents reported a minor trauma at judo training 1 week ago. Further investigation was performed with MRI and confirmed a massive hematoma much greater than previously shown by sonography. RESULTS: Histologic and microbiologic evaluation demonstrated florid inflammation and proof of Staphylococcus aureus was found intra-operatively. DISCUSSION: The diagnosis of blunt force injuries due to martial arts is difficult in childhood because often children do not remember a traumatic event. Therefore, it is important to obtain a thorough history from caregivers. Because sonography depends highly on the experience of the investigator MRI is considered to be a better diagnostic modality to diagnose and guide treatment in this age group.

Combined molecular and clinical approach for decision making for surgery in HNPCC patients: a report on three cases in two families.

Hereditary nonpolyposis colorectal cancer (HNPCC) is associated with highly penetrant germline mutations in mismatch repair genes. Due to a high lifetime risk in gene carriers for synchronous and for metachronous colorectal cancer and endometrial cancer in women, prophylactic and extended surgery are considered as options for gene carriers. A 54-year-old patient with a history of metachronous rectal cancer and a family history fulfilling the Amsterdam criteria presented with carcinoma of the cecum and highly dysplastic adenomas of the splenic flexure and descending colon. As a result of these findings, medical history and molecular diagnosis, the decision was made to perform colectomy and prophylactic hysterectomy with oophorectomy; histological examination of the specimen showed three synchronous colon carcinomas. The 31-year-old son carrying the pathogenic mutation refused to be included in the HNPCC surveillance program. One year later he presented with symptoms of bowel obstruction, and a carcinoma of the descending colon was diagnosed. Intraoperatively, in addition to the colon cancer, a small bowel cancer and peritoneal carcinomatosis were found. In another family fulfilling the Amsterdam criteria without known germline mutation a woman presented with synchronous cancer of the ascending colon and the lower rectum at the age of 49 years. Proctocolectomy and prophylactic hysterectomy were performed, which revealed an additional colon cancer and endometrial cancer. We discuss approaches for individual decision making for surgery in HNPCC patients. Is a subtotal colectomy indicated in the case of first colon cancer in HNPCC patients, or if the first tumor occurs in the lower rectum, should a proctocolectomy or a restorative proctocolectomy be considered? The aim of prospective clinical studies should be to assess acceptability, survival rates, mortality, and the quality of life in HNPCC patients who have undergone surveillance and standard oncological resections versus extended or prophylactic surgery.

Sequence analysis of the mismatch repair gene hMSH6 in the germline of patients with familial and sporadic colorectal cancer.

To evaluate the involvement of hMSH6 in colorectal cancer, the complete coding sequence and flanking intron regions of the gene were analyzed by DNA sequencing in 10 patients fulfilling Bethesda Guidelines for colorectal tumors and 10 patients with sporadic colorectal carcinoma. In addition, 10 mono- and 10 dinucleotide repeat markers were analyzed for microsatellite instability. A protein-truncating T insertion at codon 218 was identified in the index person of a hereditary non-polyposis colorectal cancer (HNPCC)-like kindred and was accompanied by a somatic T deletion in the tumor. The tumor of this patient was positive for mono- but negative for dinucleotide repeat instability and lacked allelic losses at loci frequently affected in colorectal carcinomas. A novel amino acid change, F340S, was found in a patient with sporadic colon and breast cancer and leukemia but was not detected in 246 chromosomes from healthy anonymous blood donors. In addition, we describe 2 silent and 15 intronic sequence variants not previously reported. Although the frequency is low, we present further evidence for hMSH6 germline mutations that predispose patients to HNPCC-like phenotypes and suggest that mono- and dinucleotide repeat instability testing may be useful for distinguishing between individuals harboring an hMSH2 or hMLH1 mutation and a mutation of the hMSH6 gene.

Clinical consequences of molecular diagnosis in families with mismatch repair gene germline mutations.

Hereditary nonpolyposis colorectal cancer (HNPCC), clinically defined by the Amsterdam criteria, is associated with mismatch repair gene germline mutations. This study was performed to evaluate the efficiency of combined clinical and molecular diagnostics in identifying carriers of a mutated gene in families meeting criteria of the Bethesda guidelines and to examine the influence of molecular diagnosis on clinical decision-making in carriers and noncarriers. Seventy-two patients meeting criteria of the Bethesda guidelines were tested for microsatellite instabilities (MSI). MSI-H tumors were found in 38 (52.8%) index patients. Complete sequencing of hMLH1 and hMSH2 in 38 MSI-H patients and of hMSH6 in one of these patients revealed 15 pathogenic germline mutations, including three novel mutations, and three novel unclassified germline variants. Twelve of the 15 pathogenic mutations were found in patients fulfilling the Amsterdam I/II criteria. Surgical and genetic counseling was offered to the affected families; as a result of molecular diagnosis in the 15 families, 26 index patients and affected carriers and 8 asymptomatic carriers of a mutated mismatch repair gene were included in the surveillance program, and 26 noncarriers were excluded from this program. Although germline mutations are detected in only 20.8% of patients fulfilling criteria of the Bethesda guidelines, family history and MSI-H tumor classification are both strong indicators for germline mutations in hMSH2, hMLH1, and hMSH6 genes, resulting in a 51.9% mutation detection rate. Identification of individual mutation status allows clear-cut decisions on whether or not inclusion in surveillance programs is indicated.

[Predictive molecular diagnosis and preventive surgical treatment of hereditary colorectal carcinoma: a new field of interest for surgical research]. / Prädiktive molekulare Diagnostik und präventive Chirurgie des hereditären kolorektalen Karzinoms. Ein neues Interessensgebiet der Chirurgischen Forschung.

Colorectal cancer is one of the most frequent cancers in the Western hemisphere. It seems to be well established that colorectal tumors develop as a result of an accumulation of inherited and/or acquired somatic mutational events in tumor suppressor genes and oncogenes. An increasing understanding of the molecular basis of the most prevalent colorectal cancer syndromes, such as hereditary nonpolyposis colorectal cancer (HNPCC) and familial adenomatous polyposis (FAP), is reflected by modifications in diagnosis and therapy. Therefore, strategies have been developed for predictive molecular diagnosis and preventive surgical treatment of colorectal cancer syndromes. In the future surgical research will participate in research and development in the field of molecular diagnosis of colorectal cancer and will then evaluate the clinical management concepts as a result.

[The Human Genome Project and its consequences for surgery]. / Das humane Genomprojekt und seine Konsequenzen für die Chirurgie.

The Human Genome Project is an international effort to discover all 80,000 genes of the human genome and to determine the complete sequence of the three billion basepairs of the human DNA. Chromosome mapping enables fragmentation of large DNA pieces, sequencing of the resulting small fragments and realignment in the order in which they originally occurred in the chromosomes. Identification of genes involved in various benign and malignant diseases will lead to the understanding of their action and will result in prevention-based medical approaches. In addition, novel therapeutic regimens will be devised based on human gene products. Decipherment of the genetic programs of embryogenesis will enable regeneration of various tissues without the formation of scars.

[Basic molecular biology of colon and rectal carcinoma--when differential diagnosis?]. / Molekularbiologisches Grundlagenwissen zum Kolon- und Rektumkarzinom--Wann muss differenziert diagnostiziert werden?

Colorectal cancer (CRC) is one of the most common cancers in Western populations, striking both women and men at approximately equal rates. A genetic basis for the development of cancer has already been suggested by Karl Heinrich Bauer in 1928 but only since the advancement of molecular biology direct evidence has been obtained to support the notion that cancer is a genetic disease. Recent progress in our understanding of the molecular basis of the most prevalent colorectal cancer syndromes, such as hereditary nonpolyposis colorectal cancer (HNPCC) and familial adenomatous polyposis (FAP), is reflected by modifications in diagnosis and therapy. Identification of genetic risk factors for the development of adenomas and associated carcinomas of the colon and rectum results in predictive molecular diagnosis of malignant disease and enables preventive treatment.

[Molecular diagnosis and clinical consequences in families with HNPCC syndrome]. / Molekulare Diagnostik und klinische Konsequenzen bei Familien mit HNPCC-Syndrom.

Thirteen families were included in our HNPCC surveillance program, eight of which met strict and three incomplete Amsterdam criteria. Two index patients were younger than 35 years of age. Tumors of all index persons showed microsatellite instabilities in at least 50% of the ten markers studied. Immunohistochemical analysis of tumor sections was performed using antibodies against hMLH1 and hMSH2 proteins in order to identify the mutated gene, which is not expressed in the tumor. Coding regions of hMLH1 and hMSH2 genes were amplified by PCR from genomic DNA and sequenced. In nine families pathogenetic mutations all resulting in a truncated protein, could be identified. Furthermore, 21 intron and exon polymorphisms were found. Since July 1997 we have offered surgical and genetic counseling to families with hereditary cancer syndromes in a special outpatient clinic. In addition to 13 index patients three asymptomatic gene carriers were included and eight noncarriers were excluded from the HNPCC surveillance program, as recommended by the HNPCC study group of Germany. Molecular diagnosis has considerable clinical implication in hereditary nonpolyposis colorectal cancer (HNPCC) families with respect to family members who actually have the disease as well as gene carriers and noncarriers.