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Impactions of the articular surface are relevant prognostic parameters in the treatment of acetabular fractures. Posterior marginal impactions and acetabular dome impactions may occur depending on the direction of the force vectors during trauma. Posterior marginal impactions are mainly observed in posterior fracture dislocations, while acetabular dome impactions are frequently seen in the elderly with the hip joint in extension during trauma. Femoral head impactions are also frequently associated with acetabular fractures, mainly in fracture dislocations and transverse acetabular fractures. CT scans using thin slices are mandatory in order to preoperatively identify acetabular and femoral head impactions. Intraoperatively, the reduction techniques depend on the type of marginal impaction. Posterior impactions are usually addressed via a posterior approach by applying femoral traction under direct visualization or even by performing surgical hip dislocation. Acetabular dome impactions may be reduced using the fracture lines or by creating a cortical window. Reduction is followed by filling the void with bone or bone substitutes supported by raft screws. No clear treatment recommendations for femoral head impactions are given in the literature. [ABSTRACT FROM AUTHOR]

Beginning in France in the 1960s, the management of acetabular fractures has increasingly evolved toward surgical treatment strategies. The basic principles established by the pioneers of acetabular surgery, Letournel and Judet - anatomical reconstruction of the joint and stable osteosynthesis - remain unchanged. Modern advancements in surgical techniques aim to reduce access-related trauma and minimize complications. The notable rise in acetabular fractures among the elderly, which predominantly affect the anterior aspects of the acetabulum, has driven the development of less invasive, soft tissue-sparing anterior approaches. This evolution began with the ilio-inguinal approach in the 1960s, progressed to the modified Stoppa approach in the 2000s and, most recently, the Pararectus approach in the 2010s. Each of these approaches upholds the fundamental principles of effective acetabular fracture care, while offering distinct advantages and disadvantages. In this review, we examine the merits and limitations of the Pararectus approach, specifically focusing on its utility in the surgical treatment of anterior column posterior hemitransverse acetabular fractures. Ultimately, the success of the individual patient's outcome is less dependent on the chosen approach and more on the surgeon's experience and expertise. Ideally, surgeons should be proficient in all these approaches to tailor the surgical strategy to the individual patient's requirements, thereby ensuring optimal outcomes. [ABSTRACT FROM AUTHOR]

The incidence of geriatric acetabular fractures has shown a sharp increase in the last decades. The majority of patients are male, which is different to other osteoporotic fractures. The typical pathomechanism generally differs from acetabular fractures in young patients regarding both the direction and the amount of force transmission to the acetabulum via the femoral head. Geriatric fractures very frequently involve anterior structures of the acetabulum, while the posterior wall is less frequently involved. The anterior column and posterior hemitransverse (ACPHT) fracture is the most common fracture type. Superomedial dome impactions (gull sign) are a frequent feature in geriatric acetabular fractures as well. Treatment options include nonoperative treatment, internal fixation and arthoplasty. Nonoperative treatment includes rapid mobilisation and full weighbearing under analgesia and is advisable in non- or minimally displaced fractures without subluxation of the hip joint and without positive gull sign. Open reduction and internal fixation of geriatric acetabular fractures leads to good or excellent results, if anatomic reduction is achieved intraoperatively and loss of reduction does not occur postoperatively. Primary arthroplasty of geriatric acetabular fractures is a treatment option, which does not require anatomic reduction, allows for immediate postoperative full weightbearing and obviates several complications, which are associated with internal fixation. The major issue is the fixation of the acetabular cup in the fractured bone. Primary cups, reinforcement rings or a combination of arthroplasty and internal fixation may be applied depending on the acetabular fracture type. [ABSTRACT FROM AUTHOR]

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 ± 11.7 days), delayed postoperative mobilization (2.2 ± 2.9 vs. 4.0 ± 4.9 days) and delayed mobilization after conservative treatment (1.1 ± 2.7 vs. 1.8 ± 1.9 days). 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background and Introduction: The incapacity with respect to work following anterior-inferior shoulder dislocation and subsequent Bankart repair has not been previously examined. The objective of this study was to examine a patient's incapacity according to the classification by the REFA Association. The recovery time was measured and the outcome of patients with heavy workload was compared to those with lower workloads.Materials and Methods: A total of 74 patients who underwent isolated arthroscopic Bankart repair fulfilled the inclusion criteria. The Constant-Murley Score, UCLA Shoulder Score and ROWE Score for Shoulder Instability were recorded for clinical assessment. The mean follow-up time was 43.1 months (SD ± 17.4; 24-110 months) with a mean age of 34.7 years (SD ± 12.6). Workload was classified as per the REFA Association classification system. Postoperative duration of a patient's incapacity with respect to work and other subjective ratings were provided by the patients themselves.Results: The mean incapacity of work was 2.73 months (95 % CI 1.19-5.36). The incapacity of work was 2.06 months (95 % CI 1.55-2.68) in the group with low physical strains at work (REFA 0-1) and 3.40 months (95 % CI 2.70-4.24) in the group with heavy workload (REFA 2-4/p = 0.005). Overall, the mean Constant-Murley Score was 87.7 (SD ± 13.5). The average UCLA Shoulder Score summed up to 31.9 (SD ± 3.87) and the mean ROWE Score was 87.6 (SD ± 21.7). 13 (17.5 %) patients had problems to compete in their jobs. Three patients had to change the job postoperatively.Conclusion: In this study, a relationship between the time of incapacity of work and the workload was observed; patients with low physical strains returned significantly earlier to work after arthroscopic Bankart repair (p = 0.005). In general, the clinical results as measured in the Constant/UCLA/Rowe score were comparable to other studies. [ABSTRACT FROM AUTHOR]

Type 2 diabetes mellitus (T2DM) is one of the most frequent metabolic disorders in industrialized countries. Among other complications, T2DM patients have an increased fracture risk and delayed fracture healing. We have demonstrated that supraphysiological glucose and insulin levels inhibit primary human osteoblasts׳ maturation. We aimed at developing a more physiologically relevant in vitro model to analyze T2DM-mediated osteoblast changes. Therefore, SCP-1-immortalized pre-osteoblasts were differentiated with T2DM or control (non-obese and obese) sera. Between both control groups, no significant changes were observed. Proliferation was significantly increased (1.69-fold), while AP activity and matrix mineralization was significantly reduced in the T2DM group. Expression levels of osteogenic marker genes and transcription factors were altered, e.g. down-regulation of RUNX2 and SP-7 or up-regulation of STAT1, in the T2DM group. Active TGF-β levels were significantly increased (1.46-fold) in T2DM patients׳ sera. SCP-1 cells treated with these sera showed significantly increased TGF-β signaling (2.47-fold). Signaling inhibition effectively restored osteoblast maturation in the T2DM group. Summarizing our data, SCP-1 cells differentiated in the presence of T2DM patients׳ serum exhibit reduced osteoblast function. Thus, this model has a high physiological impact, as it can identify circulating factors in T2DM patients׳ blood that may affect bone function, e.g. TGF-β. [ABSTRACT FROM AUTHOR]

Background Loss of reduction and screw perforation causes high failure rates in the treatment of proximal humerus fractures. The purpose of the present study was to evaluate the early postoperative complications using modern Dynamic Locking Screws (DLS 3.7) for plating of proximal humerus fractures. Methods Between 03/2009 and 12/2010, 64 patients with acute proximal humerus fractures were treated by angular stable plate fixation using DLSs in a limited multi-centre study. Follow-up examinations were performed three, six, twelve and twenty-four weeks postoperatively and any complications were carefully collected. Results 56 of 64 patients were examined at the six-month follow-up. Complications were observed in 12 patients (22%). In five cases (9%), a perforation of the DLS 3.7 occurred. Conclusions Despite the use of modern DLS 3.7, the early complications after plating of proximal humerus fractures remain high. The potential advantage of the DLS 3.7 regarding secondary screw perforation has to be confirmed by future randomized controlled trials. [ABSTRACT FROM AUTHOR]

Introduction Delayed bone healing is an eminent problem in the operative treatment of distal tibia fractures. To address this problem from a biomechanical perspective, the DLS 3.7 (Dynamic Locking Screw 3.7 mm) as a new generation of locking screws has been developed. This screw enables the surgeon to control the rigidity of the plate osteosynthesis and thereby to expand clinical options in cases where the bridge plating is chosen for fracture treatment. Purpose The purpose of the present prospective study was to evaluate the safety use of the DLS 3.7 in distal tibia fractures where bridge plating osteosynthesis is recommended. Methods In a prospective non-controlled cohort study, 34 patients with acute distal tibia fractures (AO 43 A-C) were treated with an angular stable plate fixation using DLS 3.7 or LHS 3.5. Followup examinations were performed three, six, twelve, and twenty-four weeks postoperatively and all registered complications were carefully collected. Results A total of 34 patients were prospectively enrolled in this study with a minimum follow-up of 6 months or obvious osseous consolidation at an earlier stage. No complications directly related to the DLS 3.7 were recorded and no infections were observed. Conclusions This observational study could show that the DLS 3.7 in combination with locking compression plates provides a secure and easy application. According to the recent literature inter-fragmentary micro-motion is one evident goal to increase the reliability in fracture healing. The new DLS 3.7 with a maximum micro-motion of 0.2 mm combines the advantage of micro-motion with the well-known advantages of angular stable plate fixation. [ABSTRACT FROM AUTHOR]

Darbepoetin (DPO), an erythropoietin (EPO) derivative, was licensed in 2002 to treat patients with solid tumors suffering from chemotherapy-dependent anemia, although various tumors express EPO to improve vascularization, thus favoring tumor growth and spreading. Therefore, we wanted to investigate direct effects of DPO on the liver tumor cell lines HepG2, SkHep1, Huh-7, AKN1, HCC-T and HCC-M, as well as on primary human hepatocytes (hHeps). DPO (0-40 ng/ml) did not affect viability of hHeps, HepG2, SkHep1, AKN1, HCC-T and HCC-M cells, as determined by Resazurin conversion. However, Huh-7 cells' viability dose-dependently decreased from 5 ng/ml DPO on. Lack of LDH release into culture medium and negative DNA laddering excluded apoptosis or necrosis as the cause for the reduced Resazurin conversion. In Huh-7 cells, DPO increased the expression of p53. Interestingly, Huh-7 cells showed the highest basal TGF-β expression as compared to the other cell lines. Upon inhibition of TGF-β signaling, DPO no longer reduced viability in Huh-7 cells. On the contrary, co-incubation with TGF-β made the other cell lines responsive to DPO. Summarizing our data, we show that DPO reduces the growth of Huh-7 cells by up-regulation of the tumor-suppressor gene p53. This mechanism seems to be dependent on a strong TGF-β expression and corresponding signaling in these cells, as other cell lines became responsive to DPO with TGF-β supplementation. The knowledge of this mechanism offers great perspectives for the understanding and treatment of solid liver tumors. [ABSTRACT FROM AUTHOR]

Background: The single-center, open-label, four-arm, exploratory study investigates the relation of different anti-diabetics to serum levels of active TGF-ß, a known pro-fibrotic stimulus, before and after a defined test meal. Findings: We investigated sera of patients with type 2 diabetes mellitus (T2DM) treated with metformin and sulfonylurea, insulin glargine or a DPP-4 inhibitor (DPP4i). Patients' sera were analyzed before and 5 h after a defined test meal at intervals of 30 min. The sulfonylurea/metformin group exhibited the highest basal levels of active TGF-ß (31.50 ± 3.58 ng/ml). The glargine/metformin group had active TGF-ß levels (24.98 ± 1.90 ng/ml) that were comparable to those of the healthy participants (22.12 ± 2.34 ng/ml). The lowest basal levels of active TGF-ß were detected in the DPP-4i/metformin group (12.28 ± 0.84 ng/ml). Following the intake of a standardized meal, active TGF-ß levels decreased (approx. 30%) in healthy subjects as well as in the sulfonylurea/metformin group and in the glargine/ metformin group. After 5 h, the active TGF-ß levels were normalized to basal levels. Active TGF-ß levels in the DPP-4i/metformin group did not change significantly after the test meal. Overall plasma levels of insulin and proinsulin were comparable between healthy participants, and T2DM patients in the glargin/metformin group and in the DPP4i/metformin group. However, no correlation between active TGF-ß levels, glucose, insulin or pro-insulin levels was detected. Conclusions: T2DM patients often exhibit elevated levels of pro-fibrotic active TGF-ß. Our results suggest that glargine/metformin and DPP4i/metformin treatment may more effectively reduce active TGF-ß serum levels than the sulfonylurea/metformin treatment. [ABSTRACT FROM AUTHOR]

Background: During the last few years, an increasing number of unstable thoracolumbar fractures, especially in elderly patients, has been treated by dorsal instrumentation combined with a balloon kyphoplasty. This combination provides additional stabilization to the anterior spinal column without any need for a second ventral approach. Case presentation: We report the case of a 97-year-old male patient with a lumbar burst fracture (type A3-1.1 according to the AO Classification) who presented prolonged neurological deficits of the lower limbs - grade C according to the modified Frankel/ASIA score. After a posterior realignment of the fractured vertebra with an internal screw fixation and after an augmentation with non-absorbable cement in combination with a balloon kyphoplasty, the patient regained his mobility without any neurological restrictions. Conclusion: Especially in older patients, the presented technique of PMMA-augmented pedicle screw instrumentation combined with balloon-assisted kyphoplasty could be an option to address unstable vertebral fractures in "a minor-invasive way". The standard procedure of a two-step dorsoventral approach could be reduced to a one-step procedure. [ABSTRACT FROM AUTHOR]

Affecting more than 230,000,000 patients, diabetes mellitus is one of the most frequent metabolic disorders in developed countries. Among other complications, diabetic patients have an increased fracture risk and show delayed fracture healing. During the disease progression, these patients' blood glucose and insulin levels vary significantly. Thus, the aim of this study was to analyze the effects of glucose and insulin on primary human osteoblasts. Although, in the presence of insulin and glucose, proliferation of osteoblasts was increased (1.2- to 1.7-fold), their alkaline phosphatase activity and, consequently, production of mineralized matrix were significantly reduced down to 55 % as compared to control cells ( p < 0.001). Interestingly, the observed effects were mainly due to stimulation with insulin. Increase in glucose did not alter osteoblasts' function significantly but further enhanced the effects of insulin. Expression of active and total transforming growth factor beta (TGF-β) was increased by glucose and insulin. Stimulation with both glucose and insulin induced gene expression changes (e.g., osteocalcin, Runx2, Satb2, or Stat1) comparable to treatment with recombinant TGF-β, further indicating osteoblasts' dysfunction. Inhibition of TGF-β signaling completely abolished the negative effects of glucose and insulin. In summary, glucose and insulin treatment causes osteoblast dysfunction, which is accompanied by an increased TGF-β expression. Blocking TGF-β signaling abrogates the functional loss observed in glucose- and insulin-treated osteoblasts, thus identifying TGF-β as a key regulator. Therefore, increased TGF-β expression during diabetes may be a feasible pathogenic mechanism underlying poor bone formation in uncontrolled diabetes mellitus. [ABSTRACT FROM AUTHOR]

Chronic lesions of the syndesmosis are uncommon and result from insufficient primary treatment. These specific treatment results are limited due to the fact of low case numbers. The interpretation of the available clinical results is therefore to be drawn with care. The majority involved patients with anatomic reconstruction, arthroscopic debridement and screw fixation. Alternative techniques include suture button fixation or arthrodesis. This article summarizes the relevant clinical experiences in treating chronic syndesmosis instability to provide necessary knowledge for practical care. [ABSTRACT FROM AUTHOR]

Purpose: To report a series of three patients with traumatic renal AV fistulas after blunt renal laceration. Methods: We retrospectively analyzed the renal trauma cases treated in the Department of Urology of Salzburg University Clinic during a time period of 10 years concerning traumatic AV fistula formation and other clinical parameters. Results: In total, 3 cases of traumatic AV fistula formation were identified in 106 blunt renal trauma patients (2.8%), with a mean age of 39 (17–56) years. All renal traumas were classified as American Association for the Surgery of Trauma (AAST) grade IV. Two patients were primarily treated with ureteral stent; one was managed conservatively. All AV fistulas were diagnosed after a mean time of 7 (1–13) days. Two patients were symptomatic with gross hematuria, and the mean time between trauma and onset of symptoms was 11 (9–13) days. All cases were managed via coil embolization after a mean of 10 (8–13) days. Two patients received a second intervention after a mean of 18 (11–25) days. The mean AV fistula size was 18.7 (12–24) mm. Mean hemoglobin loss was 3.6 g/dL. One patient received one erythrocyte concentrate. Discharge was after a mean time of 13.3 (7–12) days, with the mean time of intensive care treatment being 2.3 (1–3) days. Conclusions: Traumatic renal AV fistula is a rare but severe complication associated with higher-grade renal trauma. It can become evident through hematuria or blood loss several days after the initial trauma. The availability of coil embolization in a trauma center can help kidney preservation management. [ABSTRACT FROM AUTHOR]

Background: Loss of reduction and screw perforation causes high failure rates in the treatment of proximal humerus fractures. The purpose of the present study was to evaluate the early postoperative complications using modern Dynamic Locking Screws (DLS 3.7) for plating of proximal humerus fractures.Methods: Between 03/2009 and 12/2010, 64 patients with acute proximal humerus fractures were treated by angular stable plate fixation using DLSs in a limited multi-centre study. Follow-up examinations were performed three, six, twelve and twenty-four weeks postoperatively and any complications were carefully collected.Results: 56 of 64 patients were examined at the six-month follow-up. Complications were observed in 12 patients (22%). In five cases (9%), a perforation of the DLS 3.7 occurred.Conclusions: Despite the use of modern DLS 3.7, the early complications after plating of proximal humerus fractures remain high. The potential advantage of the DLS 3.7 regarding secondary screw perforation has to be confirmed by future randomized controlled trials. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Introduction: Open reduction and internal fixation is considered the gold standard of treatment for displaced acetabular fractures in younger patients. For elderly patients with osteoporotic bone quality, however, primary total hip arthroplasty (THA) with the advantage of immediate postoperative mobilization might be an option. The purpose of this study was to evaluate the clinical and radiological outcomes of surgical treatment of displaced osteoporotic acetabular fractures using the acetabular roof reinforcement plate (ARRP) combined with THA. Materials and methods: Between 2009 and 2019, 84 patients were operated using the ARRP combined with THA. Inclusion criteria were displaced osteoporotic fractures of the acetabulum with or without previous hemi- or total hip arthroplasty, age above 65 years, and pre-injury ability to walk at least with use of a walking frame. Of the 84 patients, 59 could be followed up after 6 months clinically and radiographically. Forty-nine (83%) were primary fractures and 10 (17%) periprosthetic acetabular fractures. Results: The mean age was 80.5 years (range 65–98 years). The average time from injury to surgery was 8.5 days (range 1–28). Mean time of surgery was 167 min (range 100–303 min). Immediate postoperative full weight bearing (FWB) was allowed for 51 patients (86%). At the 6-month follow-up, all 59 patients except one showed bony healing and incorporation of the ARRP. One case developed a non-union of the anterior column. No disruption, breakage or loosening of the ARRP was seen. Additional CT scans performed in 18 patients confirmed bony healing. Twenty-six patients (44%) had regained their pre-injury level of mobility. Complications requiring revision surgery occurred in 8 patients. Five of them were suffering from a prosthetic head dislocation, one from infection, one from hematoma and one from a heterotopic ossification. Conclusions: The ARRP has proven to provide sufficient primary stability to allow for immediate FWB in most cases and represents a valuable option for the surgical management of displaced acetabular fractures in this challenging patient group. [ABSTRACT FROM AUTHOR]

Patients with chronic liver diseases frequently exhibit decreased bone mineral densities (BMD), which is defined as hepatic osteodystrophy (HOD). HOD is a multifactorial disease whose regulatory mechanisms are barely understood. Thus, an early diagnosis and therapy is hardly possible. Therefore, the aim of our study consisted in characterizing a mouse model reflecting the human pathomechanism. Serum samples were collected from patients with chronic liver diseases and 12-week old C57Bl6/N mice after 6-week treatment with carbon tetrachloride (CCl). Repetitive injections of CCl induced liver damage in mice, resembling liver fibrosis in patients, as assessed by serum analysis and histological staining. Although CCl did not affect primary osteoblast cultures, μCT analysis revealed significantly decreased BMD, bone volume, trabecular number and thickness in CCl-treated mice. In both HOD patients and CCl-treated mice, an altered vitamin D metabolism with decreased CYP27A1, CYP2R1, vitamin D-binding protein GC and increased 7-dehydrocholesterol reductase hepatic gene expression, results in decreased 25-OH vitamin D serum levels. Moreover, both groups exhibit excessively high active transforming growth factor-beta (TGF-β) serum levels, inhibiting osteoblast function in vitro. Summarizing, our mouse model presents possible mediators of HOD, e.g. altered vitamin D metabolism and increased active TGF-β. Liver damage and significant changes in bone structure and mineralization are already visible by μCT analysis after 6 weeks of CCl treatment. This fast response and easy transferability makes it an ideal model to investigate specific gene functions in HOD. [ABSTRACT FROM AUTHOR]

Background: Although nonunions of the proximal humerus are rare, they cause significant disability to patients. Surgical reconstruction is challenging, especially with small and excavated head fragments. A promising surgical option is open reduction and stabilization using the Humerusblock device along with tension wires. The aim of this retrospective investigation was to evaluate the clinical and radiological results of this procedure.Materials and Methods: Fifteen patients with symptomatic surgical neck nonunions were treated with open reduction and internal fixation using the Humerusblock device without bone grafting. All patients showed a loss of bone stock, leading to excavated head fragments. The mean interval from injury to the described treatment was 6.2 months (range, 3.4-10.7). At a mean follow-up of 40.5 months, the Constant-Murley score was documented, pain and patient satisfaction were evaluated using a visual analogue scale, and x-rays were taken in two planes.Results: The patients' mean age was 69.7 years (range, 52-83). The mean Constant-Murley score improved from 24 points before surgery to 62 points at follow-up, which was an average of 80.8% of the score obtained for the contralateral arm. Radiological examination confirmed bony healing in 14 patients. All but one patient felt satisfied with the results. Three patients required revision surgery because of a hematoma, and early metal removal was performed in one patient because of infection.Conclusion: Nonunions of humeral surgical neck fractures can be successfully treated by fixation using the Humerusblock device along with tension wires without the need for additional bone grafting. Especially in patients with flat, concave head fragments, this procedure remains a promising reconstructive option to arthroplasty.Level Of Evidence: Level IV; Therapeutic retrospective case series. [ABSTRACT FROM AUTHOR]

Purpose: Valgus malalignment of the distal femur may be treated with corrective osteotomy. The purpose of this study was to compare the primary stability of a lateral opening-wedge osteotomy (LOWO) using a uniplanar compared to a biplanar technique. A study was carried out to test both surgeries, with both an intact medial cortex and with a deliberate attached cut of the medial cortex simulating a fracture. The primary hypothesis was that the biplanar technique provides higher axial and torsional stiffness. It was further hypothesized that the mechanical superiority of the biplanar technique would not be affected in the case of breakage of the far medial cortex.Methods: A LOWO was performed in ten synthetic femora (#3406 left large Femur, 4th Generation, Sawbones, Malmö, Sweden) using a lateral angle stable locking plate (NCB© Distal Femur Plate, Zimmer Biomet, Warsaw, USA). A uniplanar osteotomy was performed in five femora, and a biplanar osteotomy was performed in five femora. The femora were tested for axial and torsional loads using a servo-hydraulic testing machine (Instron 8874, Instron Structural Testing GmbH, High Wycombe, UK).Results: Axial stiffness decreased significantly (p = 0.001) in both groups (20% in the uniplanar group and 28 % in the biplanar group) by cutting the medial cortex. The type of osteotomy had no significant effect. A slightly lower but not statistically significant axial stiffness was seen in the biplanar group both for intact and broken medial cortices. Internal torsional stiffness dropped by more than 30% for the uniplanar group and almost 24% for the biplanar group when the cortex was cut (p < 0.001). No significant change concerning internal torsional stiffness was found between the two groups. External torsional stiffness decreased by 32% for the uniplanar group and 4% for the biplanar group after the cortical cut (p = 0.029). No significant change concerning external torsional stiffness was found between the groups, but the biplanar group showed a tendency towards higher values of external torsional stiffness.Conclusions: The axial and torsional stiffness of the implant-bone construct were not significantly affected by the type of osteotomy performed. Biplanar osteotomy tended to increase external torsional stiffness. In cases of fracture of the medial cortex, biplanar osteotomy significantly reduced the external rotation at the osteotomy and showed a significantly increased external torsional stiffness. [ABSTRACT FROM AUTHOR]

Background: Tibial plateau fractures requiring surgery are severe injuries of the lower extremity. Tibial plateau fractures have an impact not only on physically demanding jobs but notably on general professional life too. The aim of this study was to assess how the professional activity of patients will be affected after a tibial plateau fracture.Methods: 39 consecutive patients (ages 20-61 years) were retrospectively included in the study and were clinically examined at a minimum of 14 month postoperatively. Inclusion criteria were surgical treatment of tibial plateau fractures between November 2009 and December 2012. The clinical evaluation included the Lysholm score and the Oxford Knee Score. Fractures were classified and analyzed using the AO classification. Intensity of work was classified as established by the REFA Association. The patients themselves provided postoperative duration of the incapacity of work and subjective ratings.Results: 17 (43.6%) women and 22 (56.4%) men were examined with a mean follow-up of 29.7 ± 10.4 months (range 14-47). According to the AO classification there were 20 (51.3%) B-type-fractures and 19 (48.7%) C-type-fractures. The median incapacity of work was 120 days (range 10-700 days) with no significant differences between B- and C-type-fractures. Four (10.3%) patients reduced their working hours by 10.5 h per week on average. Patients with low workload (REFA 0-1, median incapacity of work 90 days, range 10-390 days) had a significant shorter incapacity of work than patients with heavy workload (REFA 2-4, median incapacity of work 180 days, range 90-700 days) (p < 0.05). The median Lysholm score decreased significantly from 100 points (range 69-100) before the injury to 73 points (range 23-100) at the time of the follow-up. All patients received postoperative physiotherapy (median 25 appointments, range 6-330), with a significant higher number of appointments for C-type-fractures than for B-type-fractures (p = 0.004).Conclusion: A relationship was found between workload and the duration of incapacity of work after tibial plateau fractures. The post-injury shift to less demanding jobs and the reduction of working hours highlight the impact of a tibial plateau fracture on a patient's subsequent physical ability to work. [ABSTRACT FROM AUTHOR]

Abstract Background Open wedge high tibial osteotomy is widespread in treating osteoarthritis of the knee. Bone healing of the gap and the necessity of bone substitutes are under discussion. Increasing movement of the osteotomy gap can improve bone healing, while excessive movement should be avoided. It was hypothesised that the use of dynamic locking screws, compared to standard locking screws, will increase interfragmental motion while construct stability persists. Methods In 20 tibia sawbones open wedge high tibial osteotomy was performed using standard locking screws or dynamic locking screws. An incremental cyclic (2 Hz) compression to termination protocol was applied using a material testing machine (MTS MiniBionix 858). Relative motion of the osteotomy and construct stability were measured using an optical tracking system (PONTOS 5M system). Levels of significance were set to 0.05. Findings 19 Sawbones were statistically evaluated. Interfragmental motion increased significantly with dynamic locking screws compared to standard locking screws (P < 0.001). Lateral hinge fractured after a mean of 29,489 (dynamic locking screws) vs. 48,111 (standard locking screws) load cycles at a median load level 3 (50–1120 N) in dynamic locking screws group and at a median load level 5 (50–1440 N) (P = 0.002) in standard locking screws group. Interpretation Using dynamic locking screws in open wedge high tibial osteotomy increases interfragmental motion within the range of optimal bone healing. A decrease in construct stability has to be considered compared to standard locking screws. Highlights • Interfragmental motion is increased using dynamic locking screws. • Osteotomy movement within the range of optimal bone healing can be expected. • Reduced construct stability has to be considered. • Lateral hinge fracture occurs earlier compared to standard locking screws. [ABSTRACT FROM AUTHOR]

Introduction: Little is known about injuries in canyoning. It was the purpose of this study to determine injury rates, patterns, causes and risk factors in canyoning; and to identify targets for future injury prevention strategies.Methods: From May to October 2015, 109 participants from 17 different countries were prospectively followed via a monthly e-mail-based questionnaire.Results: During 13,690 h of canyoning, 57 injury-events occurred. The overall injury-rate was 4.2 injuries/1000 h of canyoning. The hand (23%) and lower leg and foot (25%) were most frequently involved. Most of the injuries were mild (n = 27, 49%) and limited to the soft-tissue. There were seven severe injuries (12%) with two lateral malleolar fractures, both necessitating surgery. The majority of injuries were due to material failure (44%) and significantly more injury-events were reported when the tour included rappelling (p = 0.037). Canyoning guides suffered from significantly less injuries compared to beginners and advanced canyoneers (p < 0.001).Conclusions: The majority of canyoning injuries are mild. On the other side, roughly one-tenth suffered from severe injury. Canyoning guides are less prone to injury-events and beginners should consider performing tours with experienced guides. Notwithstanding, rappelling was the most common activity associated with an injury and the material used was deemed causative for an injury-event in almost half of all cases. Further improvement in canyoning equipment, frequent equipment service, and instructional courses to ensure adequate employment of equipment might minimize the risk of getting injured. [ABSTRACT FROM AUTHOR]

Introduction: Information about injuries and its differences in Cliff Diving (CD) and Splash Diving (SD) are unknown. It was the aim to analyse (1) injury rates, patterns and causes; (2) differences (in injuries) between both disciplines; and to (3) identify targets for future injury prevention interventions.Methods: From April to November 2013, 81 cliff and 51 splash divers were prospectively surveyed with an encrypted, monthly e-mail-based questionnaire.Results: During a total of 7857h diving with an average diving height of 13 (±7)m, an overall injury rate of 7.9 injuries/1000h of sport exposure was reported. Cliff divers most commonly suffered from injuries of the foot and ankle (18%; n=24) and neck and cervical spine (14%; n=19). In SD, the lower limb (52%; n=43) and lower back (23%; n=19) were most frequently involved. In 79% (n=49) of the cases, the injury happened while entering the water. Cliff divers were in 52% (n=15) of the injuries in a feet-first and in 14% (n=4) in a head-first position. Splash divers were in 45% (n=9) of the injuries in a back- or buttocks-first position. Most of the injuries were bruises (47%; n=104) and muscle strains (13%; n=28). The injury risk during practice was significantly higher than in competition (11.3 vs. 4.5 injuries/1000h; OR 2.5; p=0.001). The injury risk of experts (15.4/1000h exposure) was significantly higher than in professionals (6.3/1000h exposure; OR 2.4; 95% CI, 3.3-1.9; p<0.001), although the average diving height was significantly higher in professionals (19m±8 vs. 12m±6; p<0.001). Significantly more professionals performed dryland training compared to experts (p=0.006).Conclusion: Most of the injuries are related to the water entry. The entry position plays a key role in injury patterns with pursuant differences comparing CD with SD. Although most of the injuries involved soft-tissue only, severe injuries have been reported. Targets for future injury prevention strategies include protection for the increased impaction at entry; adaption of the diving conditions in practice to those in competition; dryland training courses; and instruction of non-professional divers to teach appropriate diving techniques. [ABSTRACT FROM AUTHOR]

Promotion of rhBMP2 and rhBMP7 for the routine use to support fracture healing has been hampered by high costs, safety concerns and reasonable failure rates, imposing restrictions in its clinical use. Since there is little debate regarding its treatment potential, there is rising need for a better understanding of the mode of action of these BMPs to overcome its drawbacks and promote more efficacious treatment strategies for bone regeneration. Recently, BMP9, owing to its improved osteogenic potential, is gaining attention as a promising therapeutic alternative. Our study aimed at identifying specific gene expression patterns which may predict and explain individual responses to rhBMP7 and rhBMP9 treatments. Therefore, we investigated the effect of rhBMP7 and rhBMP9 on primary human osteoblasts from 110 donors and corresponding THP-1-derived osteoclasts. This was further compared with each other and our reported data on rhBMP2 response. Based on the individual donor response, we found three donor groups profiting from rhBMP treatment either directly via stimulation of osteoblast function or viability and/or indirectly via inhibition of osteoclasts. The response on rhBMP7 treatment correlated with expression levels of the genes BAMBI, SOST, Noggin, Smad4 and RANKL, while the response of rhBMP9 correlated to the expression levels of Alk6, Endoglin, Smurf1, Smurf2, SOST and RANKL in these donors. Noteworthy, rhBMP9 treatment showed significantly increased osteogenic activity (AP activity and Smad nuclear translocation) when compared to the two clinically used rhBMPs. Based on patient's respective expression profiles, clinical application of rhBMP9 either solely or in combination with rhBMP2 and/or rhBMP7 can become a promising new approach to fit the patient's needs to promote fracture healing. [ABSTRACT FROM AUTHOR]

Background: The use of the extra-vertebral balloon osteoplasty is increasing and in the meanwhile it has become a safe surgical technique in the treatment of tibial head, distal radius and calcaneus fractures. In addition, we already could show in a biomechanical setup that the balloon osteoplasty might be a safe tool for reduction in the treatment of Hill-Sachs lesions, but clinical application has not been performed so far. Case presentation: We report the case of a 53 year-old male patient who was referred to our Trauma department (level I trauma center) after the first manifestation of a posterior shoulder dislocation due to an epileptic seizure, originated in a- up to this date unknown -glioblastoma. After closed reduction of the dislocated shoulder the X-ray showed a subcapital fracture of the proximal humerus with a large reversed Hill-Sachs lesion. We performed an open surgery via a deltoideopectoral approach and balloon osteoplasty was used to reduce the impression fracture (Hill-Sachs lesion) before fixing the fracture with a locking plate. In the post-operative CT scan we could show an anatomical reduction of the Hill-Sachs lesion. At the follow-up examination one year after surgery the patient reached full range of motion and stated no re-dislocation of the shoulder nor instability or pain. Conclusion: The reduction of an impressed humeral head fracture by use of balloon osteoplasty is a safe technique. This technique could be a new option in the treatment of Hill-Sachs lesions and might be an alternative to well known standard procedures like the remplissage or tendon transfers without affecting rotation. [ABSTRACT FROM AUTHOR]

Introduction: Indirect reduction of dia-/metaphyseal fractures with minimally invasive implant application bridges the fracture zone in order to protect the soft-tissue and blood supply. The goal of this fixation strategy is to allow stable motion at the fracture site to achieve indirect bone healing with callus formation. However, concerns have arisen that the high axial stiffness and eccentric position of locked plating constructs may suppress interfragmentary motion and callus formation, particularly under the plate. The reason for this is an asymmetric fracture movement. The biological need for sufficient callus formation and secondary bone healing is three-dimensional micro movement in the fracture zone. The DLS was designed to allow for increased fracture site motion. The purpose of the current study was to determine the biomechanical effect of the DLS_5.0. Methods: Twelve surrogate bone models were used for analyzing the characteristics of the DLS_5.0. The axial stiffness and the interfragmentary motion of locked plating constructs with DLS were compared to conventional constructs with Locking Head Screws (LS_5.0). A quasi-static axial load of 0 to 2.5 kN was applied. Relative motion was measured. Results: The dynamic system showed a biphasic axial stiffness distribution and provided a significant reduction of the initial axial stiffness of 74.4%. Additionally, the interfragmentary motion at the near cortex increased significantly from 0.033 mm to 0.210 mm (at 200N). Conclusions: The DLS may ultimately be an improvement over the angular stable plate osteosynthesis. The advantages of the angular stability are not only preserved but even supplemented by a dynamic element which leads to homogenous fracture movement and to a potentially uniform callus distribution. [ABSTRACT FROM AUTHOR]

Background: The success of shoulder stabilization with the Latarjet procedure might depend on the size of the bone graft and the positioning of the coracoid at the glenoid. The aim of this study was to quantitatively assess the surface of the coracoid bone graft and to assess its positioning in the en-face view. Method: A series of 21 patients (17 men, 4 women, 26.1 ± 6.8 years-9 right, 12 left shoulders) were prospectively included and followed up with CT scans between December 2010 and April 2012 at an average of 2.4 ± 0.7 months postoperatively. The retrospective analysis of the CT scans was performed with Osirix™ software. The coracoid surface was measured (cm) in the sagittal plane. The positioning in relation to the center of the circumscribed circle of the glenoid was determined in the en-face clock face view of the glenoid. Results: The grafts had a mean surface of 1.61 ± 0.51 cm (mean ± standard deviation). The coracoid grafts were located between 01:05 hours (32.5°) and 05:33 hours (166.6°). Mean positioning was 02:00 hours (59.8° ± 16.1°) to 04:26 hours (133.0° ± 16.9°). The extent of the grafts was 73.2° ± 14.3°. Discussion: The positioning of the coracoid graft on the clock face of the glenoid is situated in the decisive zone of 02:30-04:20 hours. The mean surface of the graft is smaller than expected from anatomical studies, but restores in defect situations bone stock in the potential defect areas at the anterior glenoid rim. Level of evidence: Level IV, prospective case series, treatment study. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the current study was to assess the clinical and radiological results after locking T-plate osteosynthesis with coracoclavicular augmentation of unstable and displaced distal clavicle fractures (Neer type 2). Methods: Thirty patients, treated between January 2007 and January 2010 were followed up after a median follow-up time of 12.2 months (range 4.7-37.2). The Constant and DASH scores were used to evaluate the clinical outcome, and anterior-posterior and 30° cephalic view radiographs were performed to assess the bony healing. Results: In all patients, the fracture healing was achieved within the first 10 weeks after surgery. All patients regained good or excellent shoulder function and returned to previous occupation and activity levels. The mean Constant and DASH scores were 92.3 points and 6.2 points, respectively. We did not observe any severe intra- or post-operative complication within the time of follow-up. Conclusion: The presented technique turned out to be a reliable method providing good results without showing severe complications. Level of evidence: Case series, Level IV. [ABSTRACT FROM AUTHOR]

Purpose: Traumatic shoulder dislocation may be complicated by concomitant bony injury of the glenoid rim or the humeral head. In Hill-Sachs lesions, reconstruction techniques vary widely and range from open reduction to tendon transposition or humeral head derotation. These operations are extensive and have questionable outcomes. With the expertise from vertebral compression fracture reduction by kyphoplasty, we examined in a cadaver feasibility study whether reduction of the Hill-Sachs lesion via hydraulic lift might be an anatomical and minimally invasive treatment option. We postulated that the use a of a balloon- assisted kyphoplasty reduction could achieve almost anatomical correction of the defect. Methods: We created Hill-Sachs lesions in six humeral specimens and performed a computed tomography (CT) scan before and after reduction with the kyphoplasty system. The entry point at the greater tuberosity and balloon positioning was visualised by fluoroscopy. The size of the Hill-Sachs lesion before and after reduction was measured using CT scans in the axial orientation. Results: Using the balloon kyphoplasty system, we achieved a statistically significant reduction (80 % ) of the Hill-Sachs lesion. Conclusion: In a preliminary cadaver study we show that using a balloon kyphoplasty system might be an alternative treatment option for Hill-Sachs lesions, with reduced collateral damage that can occur with other minimally invasive techniques. Future work is needed to evaluate the technique under arthroscopic conditions. [ABSTRACT FROM AUTHOR]

Purpose: Fractures of the tibial plateau are among the most severe injuries of the knee joint and lead to advanced gonarthrosis if the reduction does not restore perfect joint congruency. Many different reduction techniques focusing on open surgical procedures have been described in the past. In this context we would like to introduce a novel technique which was first tested in a cadaver setup and has undergone its successful first clinical application. Methods: Since kyphoplasty demonstrated effective ways of anatomical correction in spine fractures, we adapted the inflatable instruments and used the balloon technique to reduce depressed fragments of the tibial plateau. Results: The technique enabled us to restore a congruent cartilage surface and bone reduction. Conclusions: In this technique we see a useful new method to reduce depressed fractures of the tibial plateau with the advantages of low collateral damage as it is known from minimally invasive procedures. [ABSTRACT FROM AUTHOR]

Purpose: Recent reports discuss the altered bone homeostasis in cigarette smokers, being a risk factor for osteoporosis and negatively influencing fracture healing. Cigarette smoke is known to induce oxidative stress in the body via an increased production of reactive oxygen species (ROS). These increases in ROS are thought to damage the bone-forming osteoblasts. Naturally occurring polyphenols contained in green tea extract (GTE), e.g., catechins, are known to have anti-oxidative properties. Therefore, the aim of this study was to investigate whether GTE and especially catechins protect primary human osteoblasts from cigarette smoke-induced damage and to identify the underlying mechanisms. Methods: Primary human osteoblasts were isolated from patients' femur heads. Cigarette smoke medium (CSM) was obtained using a gas-washing bottle and standardized by its optical density (OD) at λ = 320 nm. ROS formation was measured using 2′7′dichlorofluorescein diacetate, and osteoblasts' viability was detected by resazurin conversion. Results: Co-, pre-, and post-incubation with GTE and catechins significantly reduced ROS formation and thus improved the viability of CSM-treated osteoblasts. Besides GTE's direct radical scavenging properties, pre-incubation with both GTE and catechins protected osteoblasts from CSM-induced damage. Inhibition of the anti-oxidative enzyme HO-1 significantly reduced the protective effect of GTE and catechins emphasizing the key role of this enzyme in GTE anti-oxidative effect. Conclusions: Our data suggest possible beneficial effects on bone homeostasis, fracture healing, and bone mineral density following a GTE-rich diet or supplementation. [ABSTRACT FROM AUTHOR]

Purpose: In this retrospective study we investigated the clinical and radiological outcome after operative treatment of acute Rockwood III-V injuries of the AC-joint using two acromioclavicular (AC) cerclages and one coracoclavicular (CC) cerclage with resorbable sutures. Methods: Between 2007 and 2009 a total of 39 patients fit the inclusion criteria after operative treatment of acute AC joint dislocation. All patients underwent open reduction and anatomic reconstruction of the AC and CC-ligaments using PDSW sutures (Polydioxane, Ethicon, Norderstedt, Germany). Thirty-three patients could be investigated at a mean follow up of 32±9 months (range 24-56 months). Results: The mean Constant score was 94.3±7.1 (range 73-100) with an age and gender correlated score of 104.2%± 6.9 (88-123%). The DASH score (mean 3.46±6.6 points), the ASES score (94.6±9.7points) and the Visual Analogue Scale (mean 0.5±0,6) revealed a good to excellent clinical outcome. The difference in the coracoclavicular distance compared to the contralateral side was <5 mm for 28 patients, between 5-10 mm for 4 patients, and more than 10 mm for another patient. In the axial view, the anterior border of the clavicle was within 1 cm (ventral-dorsal direction) of the anterior rim of the acromion in 28 patients (85%). Re-dislocations occured in three patients (9%) .Conclusion: Open AC joint reconstruction using AC and CC PDS cerclages provides good to excellent clinical results in the majority of cases. However, radiographically, the CC distance increased significantly at final follow up, but neither the amount of re-dislocation nor calcifications of the CC ligaments or osteoarthritis of the AC joint had significant influence on the outcome. Level of evidence: Case series, Level IV [ABSTRACT FROM AUTHOR]

Background: Bone morphogenic proteins (BMPs) play a key role in bone formation. Consequently, it was expected that topical application of recombinant human (rh)BMP-2 and rhBMP-7 would improve the healing of complex fractures. However, up to 36% of fracture patients do not respond to this therapy. There are hints that a systemic increase in transforming growth factor β1 (TGFβ1 ) interferes with beneficial BMP effects. Therefore, in the present work we investigated the influence of rhTGFβ1 on rhBMP signaling in primary human osteoblasts, with the aim of more specifically delineating the underlying regulatory mechanisms. Methods: BMP signaling was detected by adenoviral Smad-binding-element-reporter assays. Gene expression was determined by reverse transcription polymerase chain reaction (RT-PCR) and confirmed at the protein level by western blot. Histone deacetylase (HDAC) activity was determined using a test kit. Data sets were compared by one-way analysis of variance. Results: Our findings showed that Smad1/5/8-mediated rhBMP-2 and rhBMP-7 signaling is completely blocked by rhTGFβ1. We then investigated expression levels of genes involved in BMP signaling and regulation (for example, Smad1/5/8, TGFβ receptors type I and II, noggin, sclerostin, BMP and activin receptor membrane bound inhibitor (BAMBI), v-ski sarcoma viral oncogene homolog (Ski), Ski-related novel protein N (SnoN) and Smad ubiquitination regulatory factors (Smurfs)) and confirmed the expression of regulated genes at the protein level. Smad7 and SnoN were significantly induced by rhTGFβ1 treatment while expression of Smad1, Smad6, rhTGFβ11 and activin receptorlike kinase 1 (Alk1) was reduced. Elevated SnoN expression was accompanied by increased HDAC activity. Addition of an HDAC inhibitor, namely valproic acid, fully abolished the inhibitory effect of rhTGFβ1 on rhBMP-2 and rhBMP- 7 signaling. Conclusions: rhTGFβ1 effectively blocks rhBMP signaling in osteoblasts. As possible mechanism, we postulate an induction of SnoN that increases HDAC activity and thereby reduces the expression of factors required for efficient BMP signaling. Thus, inhibition of HDAC activity may support bone healing during rhBMP therapy in patients with elevated TGFβ serum levels. [ABSTRACT FROM AUTHOR]

The repair of large bone defects remains challenging and often requires graft material due to limited availability of autologous bone. In clinical settings, collagen sponges loaded with excessive amounts of bone morphogenetic protein 2 (rhBMP-2) are occasionally used for the treatment of bone non-unions, increasing the risk of adverse events. Therefore, strategies to reduce rhBMP-2 dosage are desirable. Silk scaffolds show great promise due to their favorable biocompatibility and their utility for various biofabrication methods. For this study, we generated silk scaffolds with axially aligned pores, which were subsequently treated with 10× simulated body fluid (SBF) to generate an apatitic calcium phosphate coating. Using a rat femoral critical sized defect model (CSD) we evaluated if the resulting scaffold allows the reduction of BMP-2 dosage to promote efficient bone repair by providing appropriate guidance cues. Highly porous, anisotropic silk scaffolds were produced, demonstrating good cytocompatibility in vitro and treatment with 10× SBF resulted in efficient surface coating. In vivo, the coated silk scaffolds loaded with a low dose of rhBMP-2 demonstrated significantly improved bone regeneration when compared to the unmineralized scaffold. Overall, our findings show that this simple and cost-efficient technique yields scaffolds that enhance rhBMP-2 mediated bone healing. [ABSTRACT FROM AUTHOR]

A response by Gunther H. Sandmann to a letter to the editor about their study on the use of balloon osteoplasty as a new treatment option for Hill-Sachs lesions in a cadaver model in a 2012 issue is presented.

A correction to the article "Trends in Epidemiology and Patho-Anatomical Pattern of Proximal Humeral Fractures" that was published in the June 20, 2014 online issue is presented.

Background: Bone morphogenic proteins (BMPs) play a key role in bone formation. Consequently, it was expected that topical application of recombinant human (rh)BMP-2 and rhBMP-7 would improve the healing of complex fractures. However, up to 36% of fracture patients do not respond to this therapy. There are hints that a systemic increase in transforming growth factor β1 (TGFβ1) interferes with beneficial BMP effects. Therefore, in the present work we investigated the influence of rhTGFβ1 on rhBMP signaling in primary human osteoblasts, with the aim of more specifically delineating the underlying regulatory mechanisms.Methods: BMP signaling was detected by adenoviral Smad-binding-element-reporter assays. Gene expression was determined by reverse transcription polymerase chain reaction (RT-PCR) and confirmed at the protein level by western blot. Histone deacetylase (HDAC) activity was determined using a test kit. Data sets were compared by one-way analysis of variance.Results: Our findings showed that Smad1/5/8-mediated rhBMP-2 and rhBMP-7 signaling is completely blocked by rhTGFβ1. We then investigated expression levels of genes involved in BMP signaling and regulation (for example, Smad1/5/8, TGFβ receptors type I and II, noggin, sclerostin, BMP and activin receptor membrane bound inhibitor (BAMBI), v-ski sarcoma viral oncogene homolog (Ski), Ski-related novel protein N (SnoN) and Smad ubiquitination regulatory factors (Smurfs)) and confirmed the expression of regulated genes at the protein level. Smad7 and SnoN were significantly induced by rhTGFβ1 treatment while expression of Smad1, Smad6, TGFβRII and activin receptor-like kinase 1 (Alk1) was reduced. Elevated SnoN expression was accompanied by increased HDAC activity. Addition of an HDAC inhibitor, namely valproic acid, fully abolished the inhibitory effect of rhTGFβ1 on rhBMP-2 and rhBMP-7 signaling.Conclusions: rhTGFβ1 effectively blocks rhBMP signaling in osteoblasts. As possible mechanism, we postulate an induction of SnoN that increases HDAC activity and thereby reduces the expression of factors required for efficient BMP signaling. Thus, inhibition of HDAC activity may support bone healing during rhBMP therapy in patients with elevated TGFβ serum levels. [ABSTRACT FROM AUTHOR]