Osteoporosis is accompanied by reduced CD274 expression in human bone marrow-derived mesenchymal stem cells.

Underlying pathomechanisms of osteoporosis are still not fully elucidated. Cell-based therapy approaches pose new possibilities to treat osteoporosis and its complications. The aim of this study was to quantify differences in human bone marrow-derived mesenchymal stem cells (hBMSCs) between healthy donors and those suffering from clinically manifest osteoporosis. Cell samples of seven donors for each group were selected retrospectively from the hBMSC cell bank of the Trauma Department of Hannover Medical School. Cells were evaluated for their adipogenic, osteogenic and chondrogenic differentiation potential, for their proliferation potential and expression of surface antigens. Furthermore, a RT2 Osteoporosis Profiler PCR array, as well as quantitative real-time PCR were carried out to evaluate changes in gene expression. Cultivated hBMSCs from osteoporotic donors showed significantly lower cell surface expression of CD274 (4.98 % ± 2.38 %) than those from the control group (26.03 % ± 13.39 %; p = 0.007), as assessed by flow cytometry. In osteoporotic patients, genes involved in inhibition of the anabolic WNT signalling pathway and those associated with stimulation of bone resorption were significantly upregulated. Apart from these changes, no significant differences were found for the other cell surface antigens, adipogenic, osteogenic and chondrogenic differentiation ability as well as proliferation potential. These findings supported the theory of an influence of CD274 on the regulation of bone metabolism. CD274 might be a promising target for further investigations of the pathogenesis of osteoporosis and of cell-based therapies involving MSCs.

[Injuries of the biceps-labrum complex : Principles, pathologies and treatment concepts]. / Verletzungen des Bizeps-Labrum-Komplexes : Grundlagen, Pathologien und Behandlungskonzepte.

BACKGROUND: The biceps-labrum complex is prone to acute lesions and degenerative changes due to its anatomical structure and the high load it has to endure. Pathological changes of these structures are common pain generators and can significantly impair shoulder function. Anatomically, the biceps-labrum complex can be divided into three zones: inside, junction and bicipital tunnel. DIAGNOSTIC PROCEDURE: Despite the focused physical examination and advancements in imaging techniques, the exact localization of pathologies remains challenging. Arthroscopy can be used to accurately diagnose inside and junctional pathologies but extra-articular changes in the region of the bicipital tunnel can only be partially visualized. TREATMENT: In cases of unsuccessful conservative treatment and correct indications, a high level of patient satisfaction can be surgically achieved. In young patients an anatomical reconstruction of inside lesions or tenodesis of the long head of the biceps tendon is performed; however, even tenotomy is a valuable option and can achieve equally satisfactory results. Unaddressed pathological changes of the bicipital tunnel can lead to persistence of pain. In clinical procedures performing tenodesis, both the different techniques and the implants used have been found to show similar results. This article describes the anatomical principles, pathological changes, the focused clinical instrumental diagnostics and discusses the different treatment philosophies as well as the outcome according to the recent literature.

Development of an intraoperative 3D C-arm technique for torsion control of femur fractures: a cadaver study.

AIM: This study aims to test the accuracy and feasibility of a measurement of femoral torsion of a 3D C-arm system (Linea aspera method) in a cadaver setting. MATERIALS AND METHODS: A total of 11 intact femora were used. Schanz screws were inserted in the femoral bone in a parallel manner with the help of a fixed drill sleeve. Femur bones were then fractured in a controlled manner and three different internal and external torsion angles were fixed with the help of a Goniometer. After that, a 3D scan was performed. The 3D data set was analyzed using a radiologic software (Visage 7, Visage Imaging Inc, USA). Measurements were then compared in the two methods with a dependent t test. RESULTS: Specific measurements for different angles did not show any differences between those two utilities. CONCLUSION: Intraoperative estimation of femoral antetorsion using a 3D C-Arm system and the Linea aspera method seems to be an accurate and feasible method. Nevertheless, more studies with higher patient numbers, comparison to CT seems to be the next step and can be recommended.

[Minimally invasive stabilization of sacral fractures]. / Minimal-invasive Stabilisierung bei Frakturen des Sakrums.

BACKGROUND: Sacral fractures can be of traumatic origin and can also occur as insufficiency fractures. While the therapeutic target of mechanically stable insufficiency fractures is mainly pain relief, mechanically unstable insufficiency fractures and traumatic sacral fractures following high-energy trauma require biomechanical stabilization. Various surgical strategies are available for this, whereby minimally invasive techniques are now preferred whenever possible. OBJECTIVE: This article presents the clinical challenges and options for minimally invasive treatment of sacral fractures. MATERIAL AND METHODS: Selected important study data are discussed and our own treatment approach is presented. RESULTS: The most important minimally invasive techniques for operative treatment of sacral fractures are presented: sacroiliac screw osteosynthesis, lumbopelvic stabilization and sacroplasty. The selection of the surgical technique should be made on an individual basis. While sacroiliac screw osteosynthesis is the international gold standard, diverse authors have also published minimally invasive techniques for lumbopelvic stabilization. The latter enables a higher mechanical stability. In contrast, sacroplasty should only be used as an alternative treatment in insufficiency fractures. Comparative studies of the described techniques are still missing. CONCLUSION: All surgical options have their indications. Nevertheless, the biomechanical stability which can be achieved differs widely. Therefore, an exact analysis should be carried out of what is necessary with respect to reduction and retention and what should be achieved when treating sacral fractures.

[Patient volume, diagnosis and injury mechanisms in a level 1 trauma center at the beginning of the COVID-19 pandemic in comparison to the mean of the 3 previous years : A retrospective, epidemiological evaluation of 4967 patients]. / Patientenaufkommen, Diagnosen und Verletzungsmechanismen eines überregionalen Traumazentrums mit Beginn der COVID-19-Pandemie im Vergleich zum Mittelwert der 3 Vorjahre : Eine retrospektive, epidemiologische Auswertung von 4967 Patienten.

BACKGROUND: As part of the COVID-19 pandemic, political decisions were made to reduce social interaction and to reduce the number of infections. The aim was to create capacities for the in-hospital care of the patients. OBJECTIVE: The aim of the study was to check whether a reduction in the number of trauma patients compared to the mean of the previous 3 years could be observed. MATERIAL AND METHODS: We retrospectively analyzed all patients who presented in the emergency admission from 1 March to 15 April 2020 with the mean of the patients from the previous 3 years 2017-2019. The age of the patients, time of presentation, diagnoses, whereabouts of the patients, inpatient or outpatient, number and duration of the operative care and required capacity on the normal ward and intensive care units (ICU) were recorded. The injury mechanism was also examined. RESULTS: A total of 4967 patients between 1 March and 15 April were included. On average over the 3 previous years, a total of 1348 patients, i.e. 29.3 patients per day were counted in our emergency room. In 2020 a total of 923, i.e. 20 patients per day (p < 0.01) were counted. On average 227 (24.6%) were admitted to hospital compared to 311.5 (23.1%) in 2020. On average 143 operations were performed compared to 136 in 2020. The days on the ward were reduced from 2442 on average for the previous years, in 2020 to 1172 days by 52.1% (p < 0.01). The number of days on the ICU was 450 days on average in previous years and 303 days in 2020 (-32.7%, p < 0.01). CONCLUSION: The number of patients in the emergency admission was significantly reduced in the observation period in 2020 compared to the mean of the previous 3 years. This directly made resources available for the care of COVID-19 patients.

Revision strategy and follow-up for implant failure in a case of combined anterior and posterior reconstruction after three-level en bloc vertebral body replacement and replacement of the aorta for chondrosarcoma of the thoracic spine.

OBJECTIVE: In 2013, we reported a case of combined anterior and posterior reconstruction after three-level en bloc vertebral body replacement and replacement of the aorta for chondrosarcoma of the thoracic spine. Eight years after, we observed an implant failure and now report on revision strategy and 2-year follow-up (f/u) after revision. METHODS: We report about the 2-year f/u of the same now 51-year-old gravedigger who needed to undergo revision surgery after implant failure. We did a combined anterior and posterior correction vertebral interbody fusion by (1) removal of broken screws in Th9 and L2, removal of broken titanium bars, correction of kyphosis, enhancement of the vertebral interbody fusion from Th8 to L4 using monoaxial titanium screws and cancellous bone transplantation and (2) removal of the broken plate and the loose cage, implantation of a novel expandable PEEK cage from Th11 to L1 and anterior stabilization from Th9/10 to L2/3, as well as autologous and allogeneic cancellous bone transplantation. RESULTS: Two years after revision surgery, the patient presented fully reintegrated without any complains. No painkillers needed to be taken. Pain was reported with 2 out of 10 on the VAS. CONCLUSION: Both procedures offer a good primary stabilization with excellent pain reduction and good return to life. Limited information on long-term survivors is known. Therefore, the theoretical advantage of a biological solution needs to be checked in the long-term f/u for consistency.

High complication and revision rates after total femoral replacement: a retrospective single center analysis of indication, function, and complication.

INTRODUCTION: Total femoral replacement (TFR) is a limb salvage procedure performed for large bony defects. However, it is often associated with major complications and reduced function. Data on limb preservation rates and functional outcomes after TFR are limited. The primary objective of this study is to assess indications, functional outcomes, and complications after TFR. MATERIALS AND METHODS: We retrospectively analyzed all patients after TFR between 2006 and 2016. All patients received a modular mega endoprosthesis (MUTARS®). Patients were grouped according to their initial indication for TFR: (1) fracture, (2) tumor, or (3) infection. We evaluated (i) patient survival, (ii) postoperative function with the Musculoskeletal Tumor Society Score (MSTS), knee strength, range of motion, and (iii) complications. RESULTS: Between 2006 and 2016, TFR was performed in 22 patients with a mean age of 64 +/-17 years. Indications for TFR were tumor (n = 6), infection (n = 8) and fracture (n = 8). The mean follow-up (f/up) was 18 months. At final follow-up, mean MSTS was 24%. Mean knee flexion strength was reduced 63% compared to the contralateral leg (p = 0.004). At time of final f/up, 5 patients (22%) died, 5 (22%) underwent secondary hip exarticulation, and 12 (54%) suffered a major complication. At f/up, 11 patients had infections. Of these 11 patients, 5 died, 4 were treated with debridement, and 5 were treated with hip exarticulation. Fifteen patients survived with preserved limbs at f/up. CONCLUSION: TFR is a salvage procedure with limited functional outcome and high complication rates. Nevertheless, the majority of our cohort could be treated successfully with limb salvage.

[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-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.

[Femoral shaft fractures]. / Femurschaftfraktur.

Femoral shaft fractures after completion of growth predominantly affect young people with healthy bones. The causes are mostly high-velocity traffic accidents, crushing or running over mechanisms and falls from a great height. Gunshot wounds are relatively rare in Germany but have a certain importance internationally and in military medicine. Accompanying injuries in local or other regions are frequent. The predominant fracture types are transverse, wedge, segment and comminuted fractures. Spiral fractures are a sign of indirect force and are therefore frequently found in older patients with osteoporosis. Atypical fractures under or following bisphosphonate treatment are a new entity, which are typically subtrochanteric and begin on the lateral side of the bone. The characteristics of pathological fractures, femoral shaft fractures in childhood and adolescence as well as periprosthetic fractures are not dealt with in this article.

[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.

[Typical alterations of frozen shoulder in MRI examinations]. / Typische Veränderungen bei der "frozen shoulder" in der bildgebenden MRT-Untersuchung.

Magnetic resonance imaging (MRI) is routinely used for the diagnostic assessment of diseases of the shoulder joint. Depending on the clinical presentation native imaging, intravenous (IV) or intra-articular injection of contrast medium can be performed (MR arthrography). Advances in imaging technology nowadays enable early detection of characteristic changes in the clinical picture of frozen shoulder. These changes typically include thickening of the coracohumeral ligament, the axillary pouch and the capsule at the rotator interval. Furthermore, obliteration of the subcoracoidal fat pad can also be observed. The MRI examinations also show a hyperintensity in the T2-weighted imaging and a contrast enhancement of the joint capsule. The alterations can show a temporal correlation with the clinical symptoms of the patient.

Limited influence of blunt aortic injuries on the outcome of polytraumatized patients: a matched pair analysis.

INTRODUCTION: Traumatic lesions of great vessels such as the aorta are life-threatening injuries. There is limited evidence about the influence of traumatic aortic injuries in multiple trauma patients in particular with regard to posttraumatic complications. The aim of this study was to evaluate the influence of blunt thoracic aortic injuries in multiple trauma patients compared to a multiple trauma cohort without this specific injury. In addition, the safety of Thoracic Endovascular Aortic Repair (TEVAR) in multiple trauma patients was analyzed. MATERIALS AND METHODS: A retrospective study was performed. We included all multiple trauma patients (ISS ≥ 16, age > 14 years) between 2005 and 2014 with (group BTAI) and without (group nBTAI) blunt traumatic aortic injuries who were treated at our level-1 trauma center. Demographic as well as clinical parameters were analyzed including injury pattern, mechanism of injury, posttraumatic complications such as ARDS, multiple organ dysfunction syndrome (MODS) and others. A matched pair analysis was performed by propensity score matching. RESULTS: In total, 721 patients were enrolled (group BTAI: n = 45; nBTAI: n = 676). In the initial study population, surgical intervention was done in n = 32 (71.1%) patients (TEVAR: n = 25; 78.1%), there was an increased AISChest and overall injury severity in group BTAI with associated significantly more posttraumatic complications in group BTAI. The matched pair analysis consisted of 42 patients per group. Beside an increased ventilation time, no significant differences were evident after the matching process. There was a trend to increased risk for SIRS using binary logistic regression analysis. CONCLUSIONS: Multiple trauma patients with blunt thoracic aortic injuries who are treated at a level-1 trauma center show a comparable outcome matched to their counterparts without aortic injuries. Our study confirms that using TEVAR in polytraumatized patients is a safe procedure. In all patients treated with TEVAR, there were no procedure-related complications, especially no neurological deficit.

[Posttraumatic torsional deformities of the forearm : Methods of measurement and decision guidelines for correction]. / Posttraumatische Torsionsfehler am Unterarm : Messmethoden und Entscheidungsleitfaden für die Korrektur.

Forearm fractures are common in all age groups. Even if the adjacent joints are not directly involved, these fractures have an intra-articular character. One of the most common complications of these injuries is a painful limitation of the range of motion and especially of pronation and supination. This is often due to an underdiagnosed torsional deformity; however, in recent years new methods have been developed to make these torsional differences visible and quantifiable through the use of sectional imaging. The principle of measurement corresponds to that of the torsion measurement of the lower limbs. Computed tomography (CT) or magnetic resonance imaging (MRI) scans are created at defined heights. By searching for certain landmarks, torsional angles are measured in relation to a defined reference line. A new alternative is the use of 3D reformation models. The presence of a torsional deformity, especial of the radius, leads to an impairment of the pronation and supination of the forearm. In the presence of torsional deformities, radiological measurements can help to decide if an operation is needed or not. Unlike the lower limbs, there are still no uniform cut-off values as to when a correction is indicated. Decisions must be made together with the patient by taking the clinical and radiological results into account.

[Torsional malalignment of the humerus]. / Torsionsfehlstellungen am Humerus.

The torsion of the humerus describes the physiological rotation of the humerus around its longitudinal axis. Various clinical and radiological methods for measurement have been described. The computed tomography method is currently the gold standard. The angle between the humeral head axis and the transepicondylar axis is measured. This angle is called retroversion. Values of retroversion vary between 10° and 40°. For the treatment of many humeral pathologies, a precise reconstruction of the anatomical retroversion is required. The retroversion of the humerus has to be considered in shoulder arthroplasty, in fracture situations and also in planning correction of posttraumatic deformities. If an orientation to the original anatomical landmarks of the humerus is no longer possible, an orientation to the contralateral side is recommended.

[Shoulder dislocations in elderly patients]. / Schulterluxationen des älteren Patienten.

In contrast to shoulder dislocations in younger patients, anterior shoulder dislocation in the elderly is often associated with concomitant injuries to the rotator cuff and fractures. There is also frequent involvement of the brachial plexus or peripheral nerves. After closed reduction and a short period of immobilization, physiotherapy should be performed to restore mobility and strength. The evaluation of the rotator cuff is essential for further treatment decisions. The majority of patients are classically treated conservatively. Elderly patients with accompanying rotator cuff lesions and failed conservative therapy can benefit from a surgical intervention. Reconstructive interventions of the rotator cuff should be principally considered; however, some individuals may benefit from a reverse prosthesis in this elderly subgroup of patients. The challenge for the treating surgeon is to exactly define the structural injury of the shoulder (which may include pre-existing lesions) and to select the optimal treatment option.

[Injury prevention in amateur football with FIFA 11+ : What is implemented on the football pitch?] / Verletzungsprävention im Amateurfußball mit FIFA 11+ : Was kommt auf dem Sportplatz an?

BACKGROUND: The warm-up and injury prevention program FIFA 11+ was developed to reduce injuries in recreational and amateur level football. Despite systematic education it is uncertain what amount of knowledge is passed down to the lower recreational level football players and what exercises are implemented in the daily routine. This study presents the summarized experiences of German coaches about the implementation of exercises on the football pitch. MATERIAL AND METHODS: In this study 142 coaches who participated in 1 (of 5) of the 2­day courses between 2013 and 2017 were sent a questionnaire. The questionnaire consisted of 24 questions, which were developed by the football union of Lower Saxony. Incomplete questionnaires were excluded from the study. RESULTS: A total of 121 questionnaires could be analyzed, which is a response rate of 85.2%. The mean time period between the 2­day training and answering the questionnaire was 29 months. Of the participating coaches 82.6% indicated that they use the program regularly (22% of the coaches use it twice a week or more frequently, 34% use it only once a week) and 6% of the coaches use additional programs to prevent injuries. A total of 86% of the participants believed in a reduction in the incidence of injuries induced by the FIFA 11+ concept, 89% of the participants rated the FIFA 11+ program as good ors very good, 91% rated the teaching concept as good or very good and 94% of the participants would recommend the 2­day advanced course to others. DISCUSSION: The prevention program as well as the advanced training concept were evaluated very positively. Most coaches use the program regularly. Nevertheless, many coaches use the FIFA 11+ exercises less than the recommended twice a week. Most coaches praised the good structure of the program, but also wished for the possibility of variations. CONCLUSION: The prevention program FIFA 11+ is seen by coaches in recreational and amateur football as an effective tool to prevent injury. Implementation on the football pitch is regular but not as frequent as the evidence-based recommendations in the training concept.

[Injury to the upper limbs and prevention in equestrian sports]. / Verletzungen der oberen Extremität und Prävention im Reitsport.

The upper limb is one of the most frequently injured body regions in equestrian sports, but it is unclear which injuries are involved, and there are no data on the associated accident mechanism. The present study is aimed at evaluating the accident mechanisms, injuries of the upper limbs, and the circumstances of the accident in equestrian sports. We included 218 patients who were all treated between 2006 and 2014 at the level I trauma center at the Medical University in Hannover because of equestrian-related accidents. The most frequent injuries were fractures and bruising in the shoulder area, fingers and hands, and the distal area of the lower arm, which were mostly caused by the horse kicking. To prevent hand injuries it is recommended that gloves are worn; the potential introduction of strengthened materials could protect the bones from severe bumping. Training in falling techniques to prevent serious injury to the upper limb would be useful. In general, primary prevention in equestrian sports should be extended to counteract the increasing neglect of protective equipment.

[Complex joint reconstruction and joint transplantation with the FLOCSAT concept-planning and surgical implementation]. / Komplexe Gelenkrekonstruktion und Gelenktransplantation mit dem FLOCSAT-Konzept ­ Planung und chirurgische Umsetzung.

Cartilage defects in adult patients are so far incurable. Fresh osteochondral allograft (OCA) transplantation is based on the insertion of mature, living, mechanically sound hyaline cartilage into an osteochondral defect where it undergoes osseointegration. Intact hyaline cartilage of OCA does not cause immune reactions in the recipient. Many reports show that small OCA have good osseointegration and show good long-term results. These observations have been incorporated into the development of the fresh large (> 10 cm2) osteochondral shell allograft transplantation (FLOCSAT) concept, which is based on the following principles: 1) the thickness of the osseous layer should be kept as thin as possible (target < 6-8 mm) so that the transplant remains stable and fixable. This results in reduced segments of vascularization, simplified ossification and reduced immunogenic bone volume. 2) The bone surface is processed and enlarged (oscillating saw: pie crust technique, drill holes) and areas of sclerosis are simultaneously broken off. 3) Cell reduction and washing out of the bony layer with a pulsatile jet lavage. 4) Prevention of impaction and dessication: cartilage with its living chondrocytes are very sensitive to mechanical contusion and dessication. When introducing the transplant, the tissue must therefore be continually moistened and the pressure acting on the cartilage must be controlled. 5) Stable fixation: extensive uniplanar osteochondral transplants cannot be inserted by the press-fit method; therefore, fixation is carried out with small implants. In this publication we demonstrate how severe and complex posttraumatic or degenerative delayed problems can be solved using FLOCSAT.