Bone marrow fat fraction assessment in regard to physical activity: KORA FF4-3-T MR imaging in a population-based cohort.

OBJECTIVES: To establish the effect of different degrees and kinds of physical activity on bone marrow fat (BMAT) content at different anatomical locations in a population-based cohort study undergoing whole-body MR imaging. METHODS: Subjects of the KORA FF4 study without known cardiovascular disease underwent BMAT fat fraction (FF) quantification in L1 and L2 vertebrae and femoral heads/necks (hip) via a 2-point T1-weighted VIBE Dixon sequence. BMAT-FF was calculated as mean value (fat image) divided by mean value (fat + water image). Physical activity was determined by self-assessment questionnaire regarding time spent exercising, non-exercise walking, non-exercise cycling, and job-related physical activity. RESULTS: A total of 385 subjects (96% of 400 available; 56 ± 9.1 years; 58% male) were included in the analysis. Exercise was distributed quite evenly (29% > 2 h/week; 31% ~ 1 h/week (regularly); 15% ~ 1 h/week (irregularly); 26% no physical activity). BMAT-FF was 52.6 ± 10.2% in L1, 56.2 ± 10.3% in L2, 87.4 ± 5.9% in the right hip, and 87.2 ± 5.9% in the left hip (all p < 0.001). Correlation of BMAT-FF between spine and hip was only moderate (r 0.42 to 0.46). Spinal BMAT-FF, but not hip BMAT-FF, was inversely associated with exercise > 2 h/week (p ≤ 0.02 vs. p ≥ 0.35, respectively). These associations remained significant after adjusting for age, gender, waist circumference, and glucose tolerance. No coherent association was found between BMAT-FF and physical activity in the less active groups. CONCLUSIONS: In our study, exercise was inversely correlated with vertebral BMAT-FF, but not hip BMAT-FF, when exercising for more than 2 h per week. Physical activity seems to affect the spine at least preferentially compared to the hip. KEY POINTS: • In our population-based cohort, at least 2 h of physical activity per week were required to show lower levels of bone marrow adipose tissue fat fraction in MRI. • Physical activity seems to affect bone marrow adipose tissue at least preferentially at the spine in contrast to the proximal femur.

Characteristics and associated risk factors of diverticular disease assessed by magnetic resonance imaging in subjects from a Western general population.

OBJECTIVES: Diverticular disease represents an increasing pathology and healthcare burden worldwide. Our aim was to study the prevalence, extent and distribution of asymptomatic diverticular disease assessed by magnetic resonance imaging (MRI) in a sample of a Western population. METHODS: Subjects from a population-based cohort study who underwent 3-T MRI were analyzed for the prevalence and extent of diverticula of the colon using an isotropic VIBE-Dixon gradient-echo sequence. The extent of diverticular disease was categorized according to the number of diverticula in each colonic segment. Univariate and adjusted analyses were performed to assess associated characteristics and risk factors. RESULTS: Among 393 subjects included in the analysis (56.4 ± 9.2 years, 57.5% males), 164 (42%) had diverticular disease, with the highest prevalence in the left-sided colonic segments (93% diverticular disease in the descending and sigmoid segment). Subjects with advanced diverticular disease were older (62.1 vs. 54.4 years) and had a higher body mass index (BMI), LDL cholesterol levels and systolic blood pressure (30.2 ± 5.1 vs. 27.8 ± 4.9 kg/m2, 149.8 ± 29.3 vs. 135.2 ± 32.9 mg/dl and 128.2 ± 14.1 vs. 118.4 ± 16.1 mmHg, respectively; all p > 0.003) compared with subjects without diverticular disease. In contrast, no significant correlation could be found for gender, physical activity, smoking status and alcohol consumption (all p > 0.31). Intra-rater reliability was excellent for all colonic segments (intra-class correlation [ICC] = 0.99-1.00), and inter-rater reliability was excellent for left- and right-sided colonic segments (ICC = 0.84-0.97). CONCLUSIONS: These findings provide insights into the disease mechanism of asymptomatic diverticular disease and may help to improve prevention of diverticulosis and its associated complications. KEY POINTS: • Overall prevalence of asymptomatic diverticular disease assessed by MRI was 42%, affecting predominantly the left-sided colon. • Asymptomatic diverticular disease was associated with age and cardiometabolic risk factors. • Magnetic resonance imaging reveals insights into the pathophysiologic mechanism of asymptomatic diverticular disease.

Evaluation of the Constant score: which is the method to assess the objective strength?

BACKGROUND: The Constant score (CS) is one of the most frequently applied tools for the assessment of the shoulder joint. However, evaluation of strength is not standardized leading to potential bias when comparing different studies. METHODS: Seventy-six patients with fractures of the proximal humerus undergoing open reduction and internal fixation (ORIF) were assessed using standardized CS strength measurements at the deltoid muscle insertion and at the wrist in three different arm positions. Variation coefficients were evaluated for each patient and position. RESULTS: Forty women (57%) and 36 men (43%) were examined 96 months in mean after ORIF. We could state a maximum of 105.3 N difference if measurements were performed at the wrist or the insertion of the deltoid muscle in 90° forward flexion on the injured arm (167.9 ± 83.1 N; 62.6 ± 29.4 N). The lowest variation coefficient of the three performed measurements could be stated at the deltoid muscle insertion in a 90° abduction position in the scapula plane (6.94 ± 5.5). CONCLUSION: Following our study results, different positions of force measurement can change the total CS by a whole category (e.g. "very good" to "good"). We recommend performing the measurement at the insertion of the deltoid muscle in a 90° abduction position in the scapula plane. Otherwise, even in the non-injured, it is hard to reach a "normal" shoulder function, based on the CS. When using the CS as outcome parameter, authors must give detailed information about the force measuring and use an exact measuring device.

Predatory journals: a major threat in orthopaedic research.

Predatory publishing is a major threat to contemporary publishing, as it offers 'to unaware scientist's', a quick open-access publication against fees without peer-review procedures.. Lack of peer-review leads to unethical practices, as plagiarism, publication of unscientific falsified data, and even unsafe clinical practices. As these journals threaten the credibility of academic publishing, significant work has been done from many scientific teams, in the last years, in establishing discriminating criteria between predatory and legitimate publishing. In the present review, we include mechanisms used by predatory editors to convince eager researchers to submit to their journals. We also provide useful links giving information about potential predatory journals and publishers, as well as scholarly writing. Joining the efforts of different scientific disciplines which compiled "green" lists with journals in their field, we conducted a "green" list with genuine orthopaedic research journals based on the directory of open-access journals (DOAJ) and Thomson Reuters journal citation reports. Ninety-six legitimate orthopaedic journals were identified based on the Thomson Reuters journal citation reports. One hundred thirty hits were found on the DOAJ site using the keywords "orthopaedics, orthopedics, sports medicine, musculoskeletal, trauma, traumatology, osteoarthritis, osteoporosis, cartilage, bone, hand, shoulder, knee, hip, foot, wound." Twenty-one journals on the DOAJ site occurred overlapping with keywords. Researchers and clinicians in the field of orthopaedics are advised to use all available tools in order to recognize predatory practices and avoid publishing in predatory journals.

Distinct Gene Expression Patterns Defining Human Osteoblasts' Response to BMP2 Treatment: Is the Therapeutic Success All a Matter of Timing?

BACKGROUND: Bone morphogenetic proteins (BMPs) play a key role in bone formation. Local application of BMP2 (Dibotermin alfa) supports bone formation when applied to complex fractures. However, up to 33% of patients do not respond to this therapy. PURPOSE: Aiming to investigate whether inter-individual responses to BMP2 treatment can be predicted by gene expression patterns, we investigated the effect of BMP2 on primary human osteoblasts and THP-1 cell-derived osteoclasts from 110 donors. METHODS: Osteoblasts were obtained by collagenase digestion of spongy bone tissues. Osteoclasts were differentiated from THP-1 cells using the conditioned media of the osteoblasts. Viability was determined by resazurin conversion. As functional characteristics AP and Trap5B activity were measured. Gene expression levels were determined by RT-PCR in 21 of the 110 evaluated donors and visualized by electrophoresis. RESULTS: Based on our data, we could classify three response groups: (i) In 51.8% of all donors, BMP2 treatment induced osteoblast function. These donors strongly expressed the BMP2 inhibitor Noggin (NOG), the alternative BMP2 receptors repulsive guidance molecule B (RGMb) and activin receptor-like kinase 6 (Alk6), as well as the Wnt inhibitor sclerostin (SOST). (ii) In 17.3% of all donors, BMP2 treatment induced viability. In these donors, the initial high SOST expression significantly dropped with BMP2 treatment. (iii) 30.9% of all donors were not directly affected by BMP2 treatment. These donors expressed high levels of the pseudoreceptor BMP and activin membrane-bound inhibitor (BAMBI) and lacked SOST expression. In all donors, SOST expression correlated directly with receptor activator of NF-κB ligand (RANKL) expression, defining the cells' potential to stimulate osteoclastogenesis. CONCLUSIONS: Our data identified three donor groups profiting from BMP2 treatment either directly via stimulation of osteoblast function or viability and/or indirectly via inhibition of osteoclastogenesis, depending on their expression of BAMBI, SOST, NOG, and RANKL. On the basis of patients' respective expression profiles, the clinical application of BMP2 as well as its timing might be modified in order to better fit the patients' needs to promote bone formation or to inhibit bone resorption.

Association between metabolic syndrome and hip osteoarthritis in middle-aged men and women from the general population.

OBJECTIVE: To investigate the impact of metabolic syndrome and its components on osteoarthritis of the hip joints compared to a healthy cohort in the KORA MRI-study. METHODS: Randomly selected men and women from the general population were classified as having metabolic syndrome, defined as presence of central obesity plus two of the following four components: elevated blood pressure (BP), elevated fasting glucose, elevated triglycerides (TG) and low HDL-cholesterol (HDL-c), or as controls without metabolic syndrome. Therefore, each subject underwent detailed assessment of waist circumference as well as fasting glucose, systolic and diastolic BP, TG, and HDL-c concentrations as well as a full-body MR scan. MR measurements were performed on a 3 Tesla scanner (Magnetom Skyra, Siemens) including a dual-echo Dixon and a T2 SS-FSE sequence for anatomical structures. In order to quantify osteoarthritis of the hip, assessment was performed by two independent, experienced radiologists for joint gap narrowing, osteophytic lipping and subchondral changes (e.g. sclerosis, pseudocysts). Associations between metabolic syndrome components and hip degeneration were estimated by logistic regression models providing odds ratios. RESULTS: Among 354 included participants (mean age: 56.1 ± 9.2 years; 55.4% male), 119 (34%) had metabolic syndrome, while 235 (66%) were part of the control group. Except for elevated blood glucose (p = 0.02), none of the metabolic syndromes' component was independently associated with osteoarthritis. Multivariable adjusted ORs for osteoarthritis of the right hip were 1.00 (95% CI 0.98;1.03), 1.00 (95% CI 0.99;1.00), 1.01 (95% CI 0.99;1.03), 1.00 (95% CI 0.97;1.04) and 1.01 (95% CI 0.96;1.06), and for the left hip 1.00 (95% CI 0.98;1.03), 1.00 (95% CI 1.00;1.01), 1.01 (95% CI 0.99;1.03), 0.99 (95% CI 0.96;1.02) and 1.04 (95% CI 0.99;1.09) for waist circumference, triglyceride, HDL-c and systolic and diastolic BP, respectively. Blood glucose was a borderline non-dependent factor for osteoarthritis of the right hip (OR: 1.02 (95% CI 1.0;1.04); p = 0.05). Furthermore, the compound metabolic syndrome was not significantly associated (OR left hip: 1.53 (95% CI 0.8;2.92), p = 0.20; OR right hip: 1.33 (95% CI 0.72;2.45), p = 0.37) with osteoarthritis of the hip joint. Age as well as gender (left hip) were the only parameters in univariate and multivariate analysis to be significantly associated with osteoarthritis of the hip joint. CONCLUSION: The compound metabolic syndrome showed no association with osteoarthritis of the hip joint. Age was the only parameter to be dependently and independently associated to osteoarthritis of both hip joints, while elevated blood glucose was independently associated with degeneration of the right hip joint.

Acetabular Fracture Resulting from a Basketball Cutting Movement in a Young Adult Male: A Case Report.

CASE: We present the case of a 26-year-old man who sustained a right transverse-posterior wall acetabular fracture while performing a cutting movement playing basketball. CONCLUSIONS: Acetabular fracture after a relatively low-energy injury in a healthy young adult male is an extremely unusual event. The cutting movement to the right likely forcefully placed the right hip in flexion, adduction, and internal rotation directing the femoral head into the posterior wall. The patient had excellent clinical and radiographic results after acetabular open reduction and internal fixation.

Isocaloric Substitution of Dietary Carbohydrate Intake with Fat Intake and MRI-Determined Total Volumes of Visceral, Subcutaneous and Hepatic Fat Content in Middle-Aged Adults.

The present study investigated the association of carbohydrate intake and isocaloric substitution with different types of fat with visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and hepatic fat content as determined by magnetic resonance imaging (MRI). Data from 283 participants (mean age 56.1 ± 9.0 years) from the MRI sub study of the KORA FF4 study were included. VAT, SAT and total body fat were quantified by a volume-interpolated VIBE-T1w-Dixon MR sequence. Hepatic fat content was determined as the proton density fat-fraction (PDFF) derived from multiecho-T1w MR sequence. Dietary intake was estimated using information provided by two different instruments, that is, repeated 24-h food lists and a food frequency questionnaire. Replacing total carbohydrates with an isoenergetic amount of total fat was significantly positively associated with VAT and hepatic fat, while there was no significant association with SAT. The multivariable adjusted ß-coefficient for replacing 5% of total energy (5E%) carbohydrates with total fat was 0.42 L (95% CI: 0.04, 0.79) for VAT. A substitution in total fat intake by 5E% was associated with a significant increase in liver fat content by 23% (p-value 0.004). If reproduced in prospective studies, such findings would strongly argue for limiting dietary fat intake.

Assessment of the Influence of Diabetes mellitus and Malnutrition on the Postoperative Complication Rate and Quality of Life of Patients in a Clinic Focused on Trauma Surgery. / Einschätzung der Auswirkungen eines Diabetes mellitus und einer Mangelernährung auf die postoperative Komplikationsrate und Lebensqualität von Patienten in einer unfallchirurgischen Schwerpunktklinik.

BACKGROUND: The prevalence of diabetes mellitus (DM) or malnutrition in hospitalised patients depends on the clinical domain, but is much higher than in the normal population. In trauma surgery, this increase is frequently associated with more postoperative complications and constantly rising costs. In addition, the quality of life of this target group is decreased, but there are only limited data from departments of traumatology and/or orthopaedics. Therefore, we aim to analyse the factors influencing the postoperative complication rate as well as the quality of life of orthopaedic and trauma patients. METHODS: Within this prospective trial in the period of 06/2014 to 02/2017, we analysed data of 1643 patients from traumatology - geriatric and septic traumatology - as well as endoprosthetics with regard to the clinical outcome, the complication rate and the quality of life (Short Form Health Survey 36, SF-36) associated with diabetes mellitus (DM) and the nutritional status (Nutritional Risk Screening 2002, NRS). RESULTS: Within our hospitalised group of trauma patients, the prevalence of diabetes mellitus was 12.4% and the risk for malnutrition (NRS ≥ 3) was 18.3%, which is much higher than in the normal population (DM 7.2%). Patients suffering from diabetes mellitus had significantly more complications than patients without diabetes mellitus. Similar results were found when comparing patients with a risk of malnutrition to the patients without. Furthermore, patients with DM evaluate their subjective quality of life lower than do patients without DM in the most domains of the SF-36, especially in the subjective-physical domains, while patients with NRS ≥ 3 assess their quality of life as being lower than do patients without a risk of malnutrition in all domains of the SF-36 (physical and mental). Additionally, we showed that reduced nutritional status has a greater influence on the decline in quality of life than did diabetes mellitus. CONCLUSION: Both diabetes mellitus and malnutrition seems to influence the subjective quality of life and the complication rate of hospitalised trauma patients. A nationwide data collection and targeted interventions within the frame of interdisciplinary cooperation are necessary. In this way, the postoperative complication rate as well as associated higher treatment costs could be reduced.

The continuous downgrading of malnutrition in the German DRG system: possible effects on the treatment of patients at risk for malnutrition.

It has been internationally recognized that malnutrition is an independent risk factor for patients' clinical outcome. A new mandatory fixed price payment system based on diagnosis-related groups (G-DRG) went into effect in 2004. The aim of our study was to demonstrate the importance of carefully coding the secondary diagnosis of "malnutrition" in the G-DRG system and to highlight how the economic relevance of malnutrition in the G-DRG system has changed from 2014 to 2016. 1372 inpatients at the Berufsgenossenschaftliche Unfallklinik (Trauma Center) in Tübingen were screened for the risk of malnutrition using Nutritional Risk Screening (NRS-2002). Patient data were compared with the NRS values collected during the study and a case simulation was carried out separately for each year. We used the codes E44.0 for NRS = 3 and E43.0 for NRS > 3. The ICD codes were entered as an additional secondary diagnosis in the internal hospital accounting system DIACOS to determine possible changes in the effective weight. In 2014 the highest additional revenue by far was calculated by coding malnutrition. For the 638 patients enrolled in the study in 2014, we were able to calculate an average additional revenue per patient coded with malnourishment of €107. In 2016, we were unable to calculate any additional revenue for the 149 patients enrolled. Although it is well known that malnutrition is an independent risk factor for poor patient outcomes, nationwide screening for a risk of malnutrition when patients are admitted to a hospital is still not required. For this reason, malnutrition in German hospitals continues to be insufficiently documented. Due to the continuous downgrading of diagnosis-related severity (CCL) of malnutrition in the G-DRG system in trauma surgery patients, it is no longer possible to refinance the costs incurred by malnourished patients through the conscientious coding of malnutrition. We assume that the indirect positive effects of nutritional interventions will have to be taken into account more in the costing calculations and possibly lead to indirect cost compensation.

Inter- and intra-observer variability of an anatomical landmark-based, manual segmentation method by MRI for the assessment of skeletal muscle fat content and area in subjects from the general population.

OBJECTIVES: Changes in skeletal muscle composition, such as fat content and mass, may exert unique metabolic and musculoskeletal risks; however, the reproducibility of their assessment is unknown. We determined the variability of the assessment of skeletal muscle fat content and area by MRI in a population-based sample. METHODS: A random sample from a prospective, community-based cohort study (KORA-FF4) was included. Skeletal muscle fat content was quantified as proton-density fat fraction (PDFF) and area as cross-sectional area (CSA) in multi-echo Dixon sequences (TR 8.90 ms, six echo times, flip angle 4°) by a standardized, anatomical landmark-based, manual skeletal muscle segmentation at level L3 vertebra by two independent observers. Reproducibility was assessed by intraclass correlation coefficients (ICC), scatter and Bland-Altman plots. RESULTS: From 50 subjects included (mean age 56.1 ± 8.8 years, 60.0% males, mean body mass index 28.3 ± 5.2) 2'400 measurements were obtained. Interobserver agreement was excellent for all muscle compartments (PDFF: ICC0.99, CSA: ICC0.98) with only minor absolute and relative differences (-0.2 ± 0.5%, 31 ± 44.7 mm2; -2.6 ± 6.4% and 2.7 ± 3.9%, respectively). Intra-observer reproducibility was similarly excellent (PDFF: ICC1.0, 0.0 ± 0.4%, 0.4%; CSA: ICC1.0, 5.5 ± 25.3 mm2, 0.5%, absolute and relative differences, respectively). All agreement was independent of age, gender, body mass index, body height and visceral adipose tissue (ICC0.96-1.0). Furthermore, PDFF reproducibility was independent of CSA (ICC0.93-0.99).  Conclusions:  Quantification of skeletal muscle fat content and area by MRI using an anatomical landmark-based, manual skeletal muscle segmentation is highly reproducible. Advances in knowledge: An anatomical landmark-based, manual skeletal muscle segmentation provides high reproducibility of skeletal muscle fat content and area and may therefore serve as a robust proxy for myosteatosis and sarcopenia in large cohort studies.

Assessment of the degree of abdominal myosteatosis by magnetic resonance imaging in subjects with diabetes, prediabetes and healthy controls from the general population.

OBJECTIVES: Intra- and intermyocellular lipid deposition and adipose tissue are part of glucose homeostasis and insulin resistance; however, their role in type 2 diabetes mellitus (T2DM) remains unclear. We assessed differences in the degree of abdominal myosteatosis among subjects with T2DM and prediabetes. MATERIALS AND METHODS: Asymptomatic subjects from the general population were classified as subjects with T2DM, prediabetes or healthy controls and underwent multi-echo Dixon magnetic resonance imaging (MRI) (TR 8.90 ms, six echo times, flip-angle 4°). Abdominal myosteatosis was quantified as proton-density fat-fraction (PDFFmuscle) by a standardized segmentation-algorithm. Cardiometabolic risk factors were prospectively obtained in a comprehensive health assessment and visceral and subcutaneous adipose tissue (VAT and SAT) were quantified semi-automatically. Uni- and multivariate quantile regression were used to examine associations. RESULTS: Among 349 included subjects (mean age: 56.0 ±â€¯8.0years, 56.7% males), 45 were classified as subjects with T2DM and 84 with prediabetes (12.9% and 24.1%; respectively). Median PDFFmuscle was significantly higher in subjects with T2DM and prediabetes compared to healthy controls (13.1% (IQR10.5-16.6%); 11.1% (IQR8.9-15.0%) and 10.1% (IQR7.5-13.3%); respectively, p < 0.001). The observed differences were independent of age and gender (all p < 0.002) but attenuated after adjustment for BMI (ß: -0.02, 95%CI: -1.49 to 1.44, p = 0.974; ß: 0.47, 95%CI: -0.91 to 1.86, p = 0.506; prediabetes and T2DM, respectively). This effect was attributable to VAT, which remained independently associated with PDFFmuscle after full adjustment (ß: 0.01, 95%CI: 0.01-0.02, p = 0.002). CONCLUSIONS: There are significant differences in the degree of abdominal myosteatosis between subjects with T2DM, prediabetes and healthy controls, that may be confounded by VAT. However, abdominal myosteatosis by MRI might serve as a cardiometabolic imaging-biomarker, specifically in the setting of impaired glucose metabolism.

TGF-ß1 impairs mechanosensation of human osteoblasts via HDAC6-mediated shortening and distortion of primary cilia.

Transforming growth factor ß (TGF-ß) is a critical regulator of bone density owing to its multiple effects on cell growth and differentiation. Recently, we have shown that TGF-ß1 effectively blocks bone morphogenetic protein (BMP) induced maturation of osteoblasts by upregulating histone deacetylase (HDAC) activity. The current study aimed at investigating the effect of rhTGF-ß1 treatment on the expression of specific HDACs and their cellular effects, e.g., microtubule structures (primary cilia) and mechanosensation. Exposure to TGF-ß1 most significantly induced expression of HDAC6 both on gene and protein level. Being most abundant in the cytoplasm HDAC6 effectively deacetylates microtubule structures. Thus, TGF-ß1-induced expression of HDAC6 led to deformation and shortening of primary cilia as well as to reduced numbers of ciliated cells. Primary cilia are described to sense mechanical stimuli. Thus, fluid flow was applied to the cells, which stimulated osteoblast function (AP activity and matrix mineralization). Compromised primary cilia in TGF-ß1-treated cells were associated with reduced osteogenic function, despite exposure to fluid flow conditions. Chemical inhibition of HDAC6 with Tubacin restored primary cilium structure and length. These cells showed improved osteogenic function especially under fluid flow conditions. Summarizing our results, TGF-ß1 impairs human osteoblast maturation partially via HDAC6-mediated distortion and/or shortening of primary cilia. This knowledge opens up new treatment options for trauma patients with chronically elevated TGF-ß1-levels (e.g., diabetics), which frequently suffer from delayed fracture healing despite adequate mechanical stimulation. KEY MESSAGES: Exposure to TGF-ß1 induces expression of HDAC6 in human osteoblasts. TGF-ß1 exposed human osteoblasts show less and distorted primary cilia. TGF-ß1 exposed human osteoblasts are less sensitive towards mechanical stimulation. Mechanosensation can be recovered by HDAC6 inhibitor Tubacin in human osteoblasts.

Malnutrition - An underestimated factor in the inpatient treatment of traumatology and orthopedic patients: A prospective evaluation of 1055 patients.

INTRODUCTION: Suboptimal nutritional status is often observed among hospitalized patients across all medical specialties. The objective of the present study was to (1) analyze the prevalence of malnutrition in hospitalized orthopedic and trauma patients and (2) to evaluate the relationship between malnutrition and selected clinical outcomes. MATERIALS AND METHODS: The prospective field study was conducted between 06/2014 and 06/2015 in a German level I trauma center (Department of Traumatology, Septic Trauma Surgery and Arthroplasty) with a total number of 1055 patients. At hospital admission, patients were checked for malnutrition using the validated Nutritional Risk Screening (NRS). Patients at risk for malnutrition were defined as NRS≥3. Quality of life (SF-36) was assessed to evaluate the physical and mental health status prior to hospitalization. Clinical outcomes under consideration included 1) rate of adverse events, 2) length of hospitalization, and 3) mobilization after operative and conservative treatment. Patients were included independently of surgical intervention or age. RESULTS: 22.3% (235) of our patients were at risk for malnutrition (NRS≥3) while a regular nutritional status (NRS<3) was diagnosed in 77.7% (819). The highest prevalence of malnutrition was found in Septic Surgery with 31.0% (106), followed by Traumatology with 19.2% (100) and Arthroplasty with 15.1% (29). Higher prevalence of malnutrition was observed among patients with typical fractures of the elderly, such as lumbar spine and pelvis (47.4%), proximal femur (36.4%) and proximal humeral (26.7%) fractures. Furthermore, patients at risk for malnutrition showed prolonged hospitalization (13.7±11.1 vs. 18.2±11.7days), delayed postoperative mobilization (2.2±2.9 vs. 4.0±4.9days) and delayed mobilization after conservative treatment (1.1±2.7 vs. 1.8±1.9days). A statistically significant correlation of NRS with each parameter (Spearman's rank correlation, p<0.05) was observed. The incidence of adverse events in patients at risk for malnutrition was statistically significantly higher compared to that of patients with a regular nutritional status (37.2% vs. 21.1%, p<0.001). CONCLUSIONS: Malnutrition is widespread regarding hospitalized patients in the field of orthopedic and trauma surgery and results in suboptimal clinical outcome. It should be considered as an important factor that significantly contributes to delayed recovery. Especially elderly trauma patients and patients suffering from postoperative infections should be monitored carefully during hospitalization.

Crucial Role of Vitamin D in the Musculoskeletal System.

Vitamin D is well known to exert multiple functions in bone biology, autoimmune diseases, cell growth, inflammation or neuromuscular and other immune functions. It is a fat-soluble vitamin present in many foods. It can be endogenously produced by ultraviolet rays from sunlight when the skin is exposed to initiate vitamin D synthesis. However, since vitamin D is biologically inert when obtained from sun exposure or diet, it must first be activated in human beings before functioning. The kidney and the liver play here a crucial role by hydroxylation of vitamin D to 25-hydroxyvitamin D in the liver and to 1,25-dihydroxyvitamin D in the kidney. In the past decades, it has been proven that vitamin D deficiency is involved in many diseases. Due to vitamin D's central role in the musculoskeletal system and consequently the strong negative impact on bone health in cases of vitamin D deficiency, our aim was to underline its importance in bone physiology by summarizing recent findings on the correlation of vitamin D status and rickets, osteomalacia, osteopenia, primary and secondary osteoporosis as well as sarcopenia and musculoskeletal pain. While these diseases all positively correlate with a vitamin D deficiency, there is a great controversy regarding the appropriate vitamin D supplementation as both positive and negative effects on bone mineral density, musculoskeletal pain and incidence of falls are reported.