The Impact of Ultrashort Pulse Laser Structuring of Metals on In-Vitro Cell Adhesion of Keratinocytes.

Besides the need for biomaterial surface modification to improve cellular attachment, laser-structuring is favorable for designing a new surface topography for external bone fixator pins or implants. The principle of this study was to observe how bioinspired (deer antler) laser-induced nano-microstructures influenced the adhesion and growth of skin cells. The goal was to create pins that allow the skin to attach to the biomaterial surface in a bacteria-proof manner. Therefore, typical fixator metals, steel, and titanium alloy were structured using ultrashort laser pulses, which resulted in periodical nano- and microstructures. Surface characteristics were investigated using a laser scanning microscope and static water contact angle measurements. In vitro studies with human HaCaT keratinocytes focused on cell adhesion, morphology, actin formation, and growth within 7 days. The study showed that surface functionalization influenced cell attachment, spreading, and proliferation. Micro-dimple clusters on polished bulk metals (DC20) will not hinder viability. Still, they will not promote the initial adhesion and spreading of HaCaTs. In contrast, additional nanostructuring with laser-induced periodic surface structures (LIPSS) promotes cell behavior. DC20 + LIPSS induced enhanced cell attachment with well-spread cell morphology. Thus, the bioinspired structures exhibited a benefit in initial cell adhesion. Laser surface functionalization opens up new possibilities for structuring, and is relevant to developing bioactive implants in regenerative medicine.

Short stem hip arthroplasty with the optimys prosthesis is a safe and effective option for obese patients: a mid-term follow-up multicenter study.

INTRODUCTION: Short stems are a valuable option in young patients undergoing total hip arthroplasty (THA) because of their bone stock preserving properties facilitating revision hip arthroplasty. Although the effect of obesity on conventional THA is well studied, data about short stem THA in obese patients are lacking. Therefore, this study aimed to investigate the influence of obesity on complications, revisions, and outcome after short stem THA. MATERIALS AND METHODS: This multicenter, observational cohort study included patients undergoing short stem THA with the optimys prosthesis. Follow-up examinations were performed at specific intervals up to 7 years postoperatively. Operation characteristics, general and specific complications, revisions, VAS rest pain, VAS load pain, VAS patient satisfaction, and Harris Hip Score (HHS) were recorded and statistically compared between obese (BMI ≥ 30 kg/m2) and non-obese (BMI < 30 kg/m2) patients. RESULTS: Of the 224 patients included with a mean follow-up of 87.2 months (range 81.9-104.0), 69 were assigned to the OB group and 155 to the non-OB group. A minimally invasive approach was significantly less often selected in obese patients (p = 0.049), whereas operating time and length of hospital stay were not significantly different. The rate of general and specific complications did not significantly differ between both groups. Survival of the optimys prosthesis was 99.1% at 7-year follow-up and one patient per group had to undergo revision surgery. VAS rest pain, load pain, and satisfaction improved from preoperatively to postoperatively in both groups without a significant difference between both groups. While the HHS was improved from preoperatively to postoperatively, obese patients showed a significantly lower HHS at the 7-year follow-up (p = 0.01) but still exhibited an excellent scoring above the PASS threshold. CONCLUSION: Short stem THA with the optimys prosthesis is a safe and effective option also in obese patients with an excellent clinical outcome and a low complication rate.

Lateral cortical notching facilitates dynamization of proximal femoral nailing - A finite element analysis.

INTRODUCTION: Dynamization of proximal femoral nailing by removal of distal interlocking is one of the recommended treatment options for nonunions of femur fractures. However, in certain inter-/subtrochanteric fractures, gliding of the nail along the femoral shaft is blocked by lateral femoral cortical support of the lag screw. For these cases, Biber et al. proposed lateral cortical notching (LCN), in which the supporting lateral bone is removed. This study investigates the biomechanical effect of LCN on gliding of proximal femoral nailing and stress distribution at the bone/implant interface. MATERIALS AND METHODS: In this finite element analysis a three-dimensional model of an unstable intertrochanteric fracture with proximal femoral nailing without distal interlocking was simulated using the FebioStudio software suite. To simulate LCN, the lag screw hole was lengthened to 15.34 mm at the lateral cortex. Displacement of the nail along the femoral shaft axis and von Mises stress distribution were compared between LCN model and standard implantation model. RESULTS: Displacement of the nail along the femoral shaft axis was higher in the LCN model than in the standard implantation model (0.48 mm vs. 0.07 mm). Highest von Mises stresses of 176-178 MPa at the implant and of 52-81 MPa at the proximal femur were detected. Maximum von Mises stresses of the implant were comparable at all sides, except for a reduced von Mises stress at the lateral inferior side in the LCN model (80 vs. 102 MPa). At the inferior lateral screw hole and the anterior/posterior lateral screw hole maximum von Mises stress was reduced in the LCN model (2 vs. 49 MPa and 52 vs. 81 MPa), whereas the maximum von Mises stress at the inferior medial screw hole was higher in the LCN model than in the standard implantation model (53 vs. 27 MPa). CONCLUSIONS: Lateral cortical notching facilitates gliding of a distally dynamized proximal femoral nail along the femoral shaft axis in intertrochanteric fractures. Additionally, the lack of lateral cortical bone support at the lag screw reduces von Mises stress at the bone/implant interface and thus could lower the risk for implant breakage and peri­implant fractures.

The development, incidence and treatment trends of trochanteric fractures in Germany: a cohort study.

BACKGROUND: Hip fractures are a major public health problem worldwide and can lead to disability, increased mortality, and reduced quality of life. We aim to provide a nationwide epidemiological analysis of trochanteric and subtrochanteric fractures and their respective surgical treatments. METHODS: Data were retrieved from the national database of the German Department of the Interior. ICD-10-GM and OPS data from the period of 2006 to 2020 were analysed and all patients with trochanteric and subtrochanteric fractures as their main diagnosis, who were treated in a German hospital, were included. Patients were grouped by age and gender and linear regression was performed where suitable to calculate statistically significant correlations between variables and incidences. RESULTS: 985,104 pertrochanteric fractures and 178,810 subtrochanteric fractures were reported during the analysed period. We calculated a mean incidence of 80.08 ± 6.34 for pertrochanteric and 14.53 ± 1.50 for subtrochanteric fractures per million inhabitants. In both fracture types, a distinct dependence of incidence on age can be determined. Incidence rates equally rise in both sexes through the age groups with an increase of about 288-fold from those under the age of 60 to those over the age of 90 in pertrochanteric fractures, and about 123-fold in subtrochanteric fractures. Intramedullary nailing was the most common kind of treatment for both fracture types with augmentative cerclages on the rise throughout the whole period. Plate and dynamic compression screws were decreasing in frequency over the analysed period in both fractures. CONCLUSIONS: We provided incidence data on per- and subtrochanteric fractures and their treatment. We calculated an economic impact of approximately 1.563 billion € per year in Germany. With regards to recent literature on costs of treatment and our findings regarding the implementation and utilization of different treatment methods, we conclude that the reinforcement of nationwide prevention programs is a relevant step in lessening the economic burden. We welcome the increased utilisation of intramedullary nailing as many studies show beneficiary outcomes and cost effectiveness in most of the included fracture types.

Developments in the epidemiology and surgical management of patella fractures in Germany.

BACKGROUND: Patella fractures account for approximately 1% of all skeletal injuries. Treatment options are vast and no definitive conclusion on what option is the most beneficial could be made so far. Plate osteosynthesis appears to gain in importance. We aim to give insight into the more recent trends and developments as well as establish the epidemiology of patella fractures in Germany by analysing treatment and epidemiological data from a national database. METHODS: Anonymised data was retrieved form a national database. In the period of 2006 to 2020, all patients with patella fractures as defined in ICD-10 GM as their main diagnosis, who were treated in a German hospital were included. Patients were divided into subgroups based on gender and age. Age groups were created in 10-year intervals from 20 years old up to 80 years old with one group each encompassing all those above the age of 80 years old and below 20 years old and younger. Linear regression was performed were possible to determine statistical significance of possible trends. RESULTS: A total of 151,435 patellar fractures were reported. 95,221 surgical interventions were performed. Women were about 1.5 times more likely to suffer from patella fracture than men. The relative number of surgical interventions rose from about 50% in 2006 to 75% in 2020. Most surgical interventions are performed in those over the age of 50. The incidence of complex fractures and plate osteosynthesis has significantly increased throughout the analysed period. CONCLUSIONS: We found a clear trend for surgical treatment in Germany with an increase in surgical procedures. We could also show that this ratio is age-related, making it more likely for younger patients in the age groups from 0 to 70 years old to receive surgical treatment for their patella fracture.

Incidence of spinal cord injuries in Germany.

PURPOSE: The goal of this study was to provide recent data on incidence of spinal cord injuries (SCI) in Germany. METHODS: The source of information was data collected via the mandatory submission of ICD-10 GM Codes by German public hospitals after patient discharge. Data from 2013 to 2020 were retrieved from the databases of the Federal Bureau of Statistics. ICD-10 Codes for acute SCI were identified. Statistical analysis was performed using Jamovi and Excel. RESULTS: A total of 10,360 patients were reported, of whom 58.7% suffered from a cervical, 30.8% a thoracic and 10.4% a lumbar lesion. Two peaks in incidence were observed at approximately 30 and 70 years old. A population-size-adjusted overall incidence of 15.73 (SD 0.77) per million per year was calculated. We calculated the incidences in several subpopulations and discovered significantly higher incidences among males and among those over the age of 60. We discovered that differences in age groups mainly concerned injuries of the upper spine, with the incidence in the lumbar spine being similar among age groups. In addition, we found that while the probability of suffering from SCI increases with age, the relative risk of suffering from a complete injury decreases. CONCLUSIONS: This study closes a long-lasting gap in epidemiological data regarding SCI in Germany, specifically by updating the incidence rates. We found that incidence depends on age, gender and type of lesion. We also provide some new angles for future research, especially considering the relative reduction in complete injuries among the elderly.

Similar Clinical Outcome in Locking and Conventional Plate Osteosynthesis for the Treatment of AO 44-B2 Ankle Fractures.

INTRODUCTION: Biomechanical studies have proved that locking plates have better primary stability besides versatility regarding fracture pattern while reducing bone contact and bridging the gap, whereas conventional nonlocking plates (plus lag screw) depend on bone-plate compression. The clinical benefit of locking plates over nonlocking plates remains unanswered, however. Therefore, this retrospective cohort study was set up to test the hypothesis that the use of locking plates for unstable ankle fractures will result in fewer re-displacements, superior bony healing, and functional and clinical outcomes better than observed in the nonlocking cohort. METHODS: Bimalleolar ankle fractures (AO 44-B2) without syndesmotic injury treated with either a locking or a nonlocking plate were included. Groups were compared for complications, bone healing, secondary dislocation, progressions of osteoarthritis, and clinical outcome using patient-reported outcome measures. RESULTS: Data revealed no clinical outcome differences (Olerud-Molander Ankle Score: nonlocking 88.2 ± 14.4, locking 88.8 ± 12.3, P = .69, robust two 1-sided test for equality (RTOST): P = .03; American Orthopaedic Foot and Ankle Score: nonlocking 91.2 ± 12.9, locking 91.8 ± 11.3, P = .96, RTOST: P = .04). Nevertheless, a significant postoperative progression of osteoarthritis was detected in both groups (P = .04). This was independent of implant (P = .16). Although difference was not significant, locking plates were preferred in older (P = .78) and sicker patients (P = .63) and in cases with severer osteoarthritis (P = .16), and were associated with a higher complication rate (P = .42) and secondary dislocation (nonlocking 9.4%, locking 18.2%; P = .42). Re-displacement, however, was not a compelling reason for revision. CONCLUSIONS: The present study shows statistically significant equality of both types of implants. Contrary to our expectation, locking plates seemed to be associated with a higher risk for re-displacement. Overall, the use of either locking or nonlocking plates for unstable AO 44-B2 fractures is safe and successful despite significant progression of osteoarthritis. LEVEL OF EVIDENCE: III, Retrospective observational cohort study.

The Correlation between Cervical Fusion Length and Functional Outcomes in Patients with Traumatic Spinal Cord Damage-A Registry-Based Cohort Study.

This study aims to assess if there is an evident correlation between fusion length and rehabilitation success after trauma to the cervical spine that could potentially be used to predict functional outcomes. This monocentric study was conducted in the Spinal-Cord-Injury center of the Berufsgenossenschaftliches Klinikum Hamburg. Data sets of 199 patients from the Spinal-Cord-Injury center admitted between the beginning of 2003 and the end of 2018 were subjected to statistical analyses. The Spinal Cord Independence Measure II (SCIM II) difference between admission and discharge was chosen as the primary outcome variable of a multiple linear regression analysis, including several other variables. The length of fusion, SCIM at admission and the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) values at admission could be identified as significant predictors. The cervical fusion length could be identified as an independent predictor of the functional outcome within our model. This correlation most likely mediates for the range of motion as well as partly for injury severity. This is much harder to evaluate in a newly admitted rehabilitation patient than a single numerical value that represents its rehabilitative implications, such as fusion length. Together with an initial assessment of the SCIM and ISNCSCI, it provides a solid basis for outcome prediction.

Biomechanical in vitro analysis of a novel flexible implant for pubic symphysis disruption using an ultra-high molecular weight polyethylene fiber cord.

BACKGROUND: Plate osteosynthesis depicts the gold standard to surgically treat pubic symphysis disruptions. However, high rates of implant failure after plate osteosynthesis are reported, probably because of the iatrogenic arthrodesis of this fibrocartilaginous joint. Therefore, flexible implants for treatment of pubic symphysis disruptions appear to be a sensible solution. METHODS: In this biomechanical screening study, we designed and investigated a flexible implant, which consists of two plates connected with an ultra-high molecular weight polyethylene fiber cord. We mechanically tested eye splices as a possible fixation method of the cords by performing tensile load to failure tests. Afterwards, we developed a biomechanically appropriate plate design and cord routing between the plates. Finally, we biomechanically tested the flexible implant under tensile and shear loading until failure. FINDINGS: When fixing a 1 mm ultra-high molecular weight polyethylene fiber cord with eye splices, a load at failure of 1570.74 N was detected under tensile loading. None of the eye splices failed but the cords itself ruptured. The load at failure of the designed cord routing in criss-cross technique and fixation within the plates amounts 4742.09 N under tensile and 2699.77 N under shear load. INTERPRETATION: We developed a novel flexible implant for repair of pubic symphysis disruptions using ultra-high molecular weight polyethylene fiber cords connected to osteosynthesis plates. We identified eye splices as a mechanically optimal fixation method and proved that the ultra-high molecular weight polyethylene fiber cord routing and fixation of the flexible implant clearly withstands physiological forces acting on the pubic symphysis.

Protein Expression of AEBP1, MCM4, and FABP4 Differentiate Osteogenic, Adipogenic, and Mesenchymal Stromal Stem Cells.

Mesenchymal stem cells (MSCs) gain an increasing focus in the field of regenerative medicine due to their differentiation abilities into chondrocytes, adipocytes, and osteoblastic cells. However, it is apparent that the transformation processes are extremely complex and cause cellular heterogeneity. The study aimed to characterize differences between MSCs and cells after adipogenic (AD) or osteoblastic (OB) differentiation at the proteome level. Comparative proteomic profiling was performed using tandem mass spectrometry in data-independent acquisition mode. Proteins were quantified by deep neural networks in library-free mode and correlated to the Molecular Signature Database (MSigDB) hallmark gene set collections for functional annotation. We analyzed 4108 proteins across all samples, which revealed a distinct clustering between MSCs and cell differentiation states. Protein expression profiling identified activation of the Peroxisome proliferator-activated receptors (PPARs) signaling pathway after AD. In addition, two distinct protein marker panels could be defined for osteoblastic and adipocytic cell lineages. Hereby, overexpression of AEBP1 and MCM4 for OB as well as of FABP4 for AD was detected as the most promising molecular markers. Combination of deep neural network and machine-learning algorithms with data-independent mass spectrometry distinguish MSCs and cell lineages after adipogenic or osteoblastic differentiation. We identified specific proteins as the molecular basis for bone formation, which could be used for regenerative medicine in the future.

Biomechanical analysis of fixation methods in acetabular fractures: a systematic review of test setups.

PURPOSE: Optimal anatomical reduction and stable fixation of acetabular fractures are important in avoiding secondary dislocation and osteoarthritis. Biomechanical studies of treatment options of acetabular fractures aim to evaluate the biomechanical properties of different fixation methods. As the setup of the biomechanical test can influence the experimental results, this review aimed to analyze the characteristics, comparability and clinical implications of studies on biomechanical test setups and finite element analyses in the fixation of acetabular fractures. METHODS: A systematic literature research was conducted according to the PRISMA guidelines, using the PubMed/MEDLINE and Web of Science databases. 44 studies conducting biomechanical analyses of fixation of acetabular fractures were identified, which met the predefined inclusion and exclusion criteria and which were published in English between 2000 and April 16, 2021. The studies were analyzed with respect to distinct parameters, including fracture type, material of pelvis model, investigated fixation construct, loading direction, loading protocol, maximum loading force, outcome parameter and measurement method. RESULTS: In summary, there was no standardized test setup within the studies on fixation constructs for acetabular fractures. It is therefore difficult to compare the studies directly, as they employ a variety of different test parameters. Furthermore, the clinical implications of the biomechanical studies should be scrutinized, since several test parameters were not based on observations of the human physiology. CONCLUSION: The limited comparability and restricted clinical implications should be kept in mind when interpreting the results of biomechanical studies and when designing test setups to evaluate fixation methods for acetabular fractures.

Evidence-Based Examination Techniques for the Shoulder Joint. / Evidenzbasiertes Lehrvideo für Untersuchungstechniken am Schultergelenk.

OBJECTIVE: Digitalisation now almost covers all areas of medical student teaching. Teaching videos are a good way to help students learn practical skills. The existing evidence is a recognised aid for the classification of the respective technology. METHOD: This video presents the usual examination techniques of the shoulder joint on a patient with an unstable shoulder. The respective techniques, if available, were backed up with appropriate evidence. CONCLUSION: The examination techniques presented allow students to view them in a standardized manner on a patient. The evidence for the examination techniques can help with the classification of the respective technique.

Percutaneous administration of allogeneic bone-forming cells for the treatment of delayed unions of fractures: a pilot study.

BACKGROUND: Overall, 5-10% of fractures result in delayed unions or non-unions, causing major disabilities and a huge socioeconomic burden. Since rescue surgery with autologous bone grafts can cause additional challenges, alternative treatment options have been developed to stimulate a deficient healing process. This study assessed the technical feasibility, safety and preliminary efficacy of local percutaneous implantation of allogeneic bone-forming cells in delayed unions of long bone fractures. METHODS: In this phase I/IIA open-label pilot trial, 22 adult patients with non-infected delayed unions of long bone fractures, which failed to consolidate after 3 to 7 months, received a percutaneous implantation of allogeneic bone-forming cells derived from bone marrow mesenchymal stem cells (ALLOB; Bone Therapeutics) into the fracture site (50 × 106 to 100 × 106 cells). Patients were monitored for adverse events and need for rescue surgery for 30 months. Fracture healing was monitored by Tomographic Union Score (TUS) and modified Radiographic Union Score. The health status was evaluated using the Global Disease Evaluation (GDE) score and pain at palpation using a visual analogue scale. The presence of reactive anti-human leukocyte antigen (HLA) antibodies was evaluated. RESULTS: During the 6-month follow-up, three serious treatment-emergent adverse events were reported in two patients, of which two were considered as possibly treatment-related. None of the 21 patients in the per-protocol efficacy population needed rescue surgery within 6 months, but 2/21 (9.5%) patients had rescue surgery within 30 months post-treatment. At 6 months post-treatment, an improvement of at least 2 points in TUS was reached in 76.2% of patients, the GDE score improved by a mean of 48%, and pain at palpation at the fracture site was reduced by an average of 61% compared to baseline. The proportion of blood samples containing donor-specific anti-HLA antibodies increased from 8/22 (36.4%) before treatment to 13/22 (59.1%) at 6 months post-treatment, but no treatment-mediated allogeneic immune reactions were observed. CONCLUSION: This pilot study showed that the percutaneous implantation of allogeneic bone-forming cells was technically feasible and well tolerated in patients with delayed unions of long bone fractures. Preliminary efficacy evidence is supporting the further development of this treatment. TRIAL REGISTRATION: NCT02020590 . Registered on 25 December 2013. ALLOB-DU1, A pilot Phase I/IIa, multicentre, open proof-of-concept study on the efficacy and safetyof allogeneic osteoblastic cells (ALLOB®) implantation in non-infected delayed-union fractures.

Evidence-Based Examination Techniques for the Knee. / Evidenzbasiertes Lehrvideo für Untersuchungstechniken am Kniegelenk.

OBJECTIVE: Digitalisation now almost covers all areas of medical student teaching. Teaching videos are a good way to help students learn practical skills. The existing evidence is a recognised aid for the classification of the respective technology. METHOD: This video presents the usual examination techniques of the knee joint on a patient with an unstable knee. The respective techniques, if available, were backed up with the appropriate evidence. CONCLUSION: The examination techniques presented allow students to view the examination techniques in a standardised manner on a patient. The evidence for the examination techniques can help with the classification of the respective technique. ZIELSETZUNG: Die Digitalisierung erfasst inzwischen alle Bereiche der studentischen Lehre. Um die Studierenden im Erlernen praktischer Fertigkeiten zu unterstützen, sind Lehrvideos eine gute Methode. Für die Einordnung der jeweiligen Technik ist die vorhandene Evidenz eine anerkannte Hilfestellung. METHODE: Das hier vorliegende Video stellt die üblichen Untersuchungstechniken des Kniegelenkes an einer Patientin mit einem instabilen Knie dar. Die jeweiligen Techniken wurden, wenn vorhanden, mit der jeweiligen Evidenz unterlegt. SCHLUSSFOLGERUNG: Die dargestellten Untersuchungstechniken ermöglichen es Studierenden, sich die Untersuchungstechniken standardisiert an einem Patienten anzuschauen. Die eingeblendete Evidenz für die Untersuchungstechniken kann hierbei eine Hilfestellung bei der Einordnung der jeweiligen Technik leisten.

Quality of life of persons with transfemoral amputation: Comparison of socket prostheses and osseointegrated prostheses.

BACKGROUND: Until recently, no study had compared the quality of life of persons with transfemoral amputation treated with osseointegration to socket prosthesis users. OBJECTIVES: Comparison of quality of life in two types of prostheses users: a cohort of patients with osseointegration and patients equipped with a socket prosthesis who were group-matched for age, body mass index and mobility grade. STUDY DESIGN: A cross-sectional study that compared METHODS:: The quality of life of 39 participants (22 in the osseointegration group and 17 in the socket prosthesis group) was measured using the Questionnaire for Persons with Transfemoral Amputation (Q-TFA) and European Questionnaire 5-dimension 3-level (EQ-5D-3L) surveys. RESULTS: Compared with the socket prosthesis group, the osseointegration group had a significantly higher 'Global' score (p = 0.022) and a significantly lower 'Problem' score (p < 0.001) of the Q-TFA. The 'Mobility' (p = 0.051) and 'Use' scores (p = 0.146) of the Q-TFA, the EQ-5D-3L index (p = 0.723), and EQ-5D visual analog scale (p = 0.497) showed no significant differences between groups. CONCLUSIONS: Patients with osseointegration experienced less prosthesis-associated problems than socket prosthesis users and had a higher prosthesis-associated quality of life when assessed with the Q-TFA. General quality of life, as assessed with the EQ-5D-3L, was not different between groups.

Checklist Focused on Patients for Making of Teaching Videos in Orthopedic Surgery. / Patientenorientierte Checkliste für die Erstellung von Lehrvideos für Orthopädie und Unfallchirurgie.

INTRODUCTION: The focus of medical-didactic research is the improvement of clinical-practical training. One way to support practical skills training in a time- and resource-saving way is to provide instructional videos. Often the freely available instructional videos do not meet didactic or content requirements. Creating your own videos can therefore be a useful alternative for teachers. There are a variety of instructions on the Internet for shooting instruction videos. To date, this does not include any concrete instructions/assistance for the production of medical instructional videos. However, the presentation of medical learning content in particular can contain many hurdles. The aim of this work was to design a checklist for the creation of instructional videos, which can be used as a guide. METHODS: As a first step, a systematic literature search was carried out to identify works that deal with the creation and not the use of medical instructional videos. To date, corresponding publications do not exist. In a workshop, the participants, who already gained experience in creating this type of video, exchanged ideas. These were critically discussed and analyzed. As a result, a checklist was created. In a subsequent multi-step review process, the checklist was reviewed with regard to applicability, comprehensibility, completeness and quality of the items. RESULTS: Four phases in the creation of an instructional video could be differentiated: preliminary reflections, preparation, day of filming, post-production. The checklist is structured accordingly and should be actively processed phase by phase. The checklist is created in such a way that it can be used and edited without reading this text. Particular focus is placed on the patient and his needs. CONCLUSION: The checklist created provides useful help in the creation of medical instructional videos and can for the first time serve as a guide especially for orthopedic and accident surgical instructional videos.

Internship Experience in Orthopaedics and Traumatology and its Impact on Becoming a Specialist. / Praktisches Jahr in Orthopädie und Unfallchirurgie ­ die kollegiale Staffelstabübergabe in die Weiterbildung?

INTRODUCTION: The German practical year is the last clinical placement period during Medical School. However, it remains unclear how medical students evaluate the practical year in orthopaedics and traumatology (Orthopädie und Unfallchirurgie; O & U) and whether it has an impact on becoming an O & U specialist. METHOD: We analysed data of 146 medical students (46,7% female) who completed the placement in O & U. From the evaluation, 37 items were included in the analyses. Participants who could imagine becoming an O & U specialist (O & U-Ja) following graduation were statistically compared to those who could not (O & U-Nein). RESULTS: Overall 123 (83.7%) trainees indicated that they would like to become an O & U specialist (O & U-Ja), 18 (12.8%) negated (O & U-Nein) and 6 (4.1%) were undecided. Groups did not differ for sex and age (sex: Chi² = 2.50, p = 0.114; age: F [1.93] < 1, p = 0.764). Group differences were found for practical orientation, independency, acquisition of anamnesis and diagnostics skills and problem-solving expertise with students who could imagine becoming an O & U specialist (O & U-Ja) giving the highest ratings. DISCUSSION: Evaluations of the last medical year are essential in order to continuously improve the internship experience and to attract students towards a certain medical field and, moreover, to post-graduate specialist training. Clinics and institutions who already emphasize on the factors derived from this evaluation, or are continuously working on improvement, might be more able to attract young professionals, since personnel acquisition is starting early in the medical field.

Study of the tribological properties of surface structures using ultrashort laser pulses to reduce wear in endoprosthetics.

BACKGROUND: Loosening of prostheses and functional disorders represent a far-reaching problem in the clinic, and the long-term outcomes are essentially determined by wear. Despite all advances, up to 10% of prostheses still fail after 10 years. In particular, more active patients show increased revision rates. METHODS: The objective of this thesis is to examine whether the applied microstructures of the articulating surfaces can lead to a reduction in abrasion. Three different structural geometries (dimples, offset lines, grid lines) were defined. In an experimental test setup according to DIN ISO 6474 (Deutsches Institut für Normung, International Organization for Standardization), a tribological test of metal and ceramic pairings was performed using two-dimensional ring-on-disc (RoD) tests. RESULTS: In both material groups, the structuring had a positive effect on the wear behaviour. In the ceramic group, an abrasion reduction of 22.6% was achieved. However, it is important to take into account the limited informative value due to the hardness of the material. Two of the three Cobalt-Chrome-Molybdenum (CoCrMo) structure geometries (grids, offset lines) also showed a significant reduction in abrasion compared to the reference group, with a maximum wear reduction of 55.5%. CONCLUSION: By reducing abrasion, surface structuring could be used to extend the life of prostheses and minimise the number of revisions.

Autologous Iliac Bone Graft Compared with Biphasic Hydroxyapatite and Calcium Sulfate Cement for the Treatment of Bone Defects in Tibial Plateau Fractures: A Prospective, Randomized, Open-Label, Multicenter Study.

BACKGROUND: Bone-graft substitutes are commonly used for the augmentation of traumatic bone defects in tibial plateau fractures. However, their clinical performance compared with that of autologous bone-grafting, the gold standard in bone defect reconstruction, still remains under debate. This study investigates the differences in quality of life, pain, and radiographic outcomes in the treatment of tibial plateau fracture-associated bone defects with either autologous bone grafts or a bioresorbable hydroxyapatite and calcium sulfate cement (CERAMENT BONE VOID FILLER [CBVF]; BONESUPPORT). METHODS: In this study, 135 patients with acute depression and split-depression fractures of the proximal part of the tibia (OTA/AO types 41-B2 and 41-B3) were enrolled in a prospective, controlled, randomized, multicenter trial including 20 hospitals in Germany. Patients were randomized to receive either autologous iliac bone graft or CBVF for reconstruction of the bone defect. The primary outcome measures were the Short Form (SF)-12 version 2 Physical Component Summary (PCS) score at week 26 (the study was designed to show noninferiority of the CBVF with regard to the PCS with a prespecified margin of -5 points) and the pain level at 26 weeks postoperatively measured by a visual analog scale (VAS). The secondary outcomes were the SF-12 version 2 Mental Component Summary (MCS) and SF-12 PCS scores at weeks 1, 6, and 12 and bone-healing on radiographs. RESULTS: Age, sex, fixation methods, and fracture pattern were comparable in both groups. There were no significant differences (p > 0.05) in the SF-12 PCS or VAS scores at postoperative week 26. There was a significant reduction of blood loss (p = 0.007) and pain levels (p = 0.008) at postoperative day 1 in the CBVF group. The rates of fracture-healing, defect remodeling, and articular subsidence were not significantly different (p > 0.05) in both groups. CONCLUSIONS: Bioresorbable CBVF was noninferior to autologous bone graft with regard to both patient-reported and radiographic outcomes in tibial plateau fractures of OTA/AO types 41-B2 and 41-B3. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Validating a transnational fracture treatment registry using a standardized method.

AIM: Subsequent to a three-month pilot phase, recruiting patients for the newly established BFCC (Baltic Fracture Competence Centre) transnational fracture registry, a validation of the data quality needed to be carried out, applying a standardized method. METHOD: During the literature research, the method of "adaptive monitoring" fulfilled the requirements of the registry and was applied. It consisted of a three-step audit process; firstly, scoring of the overall data quality, followed by source data verification of a sample size, relative to the scoring result, and finally, feedback to the registry on measures to improve data quality. Statistical methods for scoring of data quality and visualisation of discrepancies between registry data and source data were developed and applied. RESULTS: Initially, the data quality of the registry scored as medium. During source data verification, missing items in the registry, causing medium data quality, turned out to be absent in the source as well. A subsequent adaptation of the score evaluated the registry's data quality as good. It was suggested to add variables to some items in order to improve the accuracy of the registry. DISCUSSION: The application of the method of adaptive monitoring has only been published by Jacke et al., with a similar improvement of the scoring result following the audit process. Displaying data from the registry in graphs helped to find missing items and discover issues with data formats. Graphically comparing the degree of agreement between the registry and source data allowed to discover systematic faults. CONCLUSIONS: The method of adaptive monitoring gives a substantiated guideline for systematically evaluating and monitoring a registry's data quality and is currently second to none. The resulting transparency of the registry's data quality could be helpful in annual reports, as published by most major registries. As the method has been rarely applied, further successive applications in established registries would be desirable.