Risk of symptomatic heterotopic ossification following plate osteosynthesis in multiple trauma patients: an analysis in a level-1 trauma centre

<p>Abstract</p> <p>Background</p> <p>Symptomatic heterotopic ossification (HO) in multiple trauma patients may lead to follow up surgery, furthermore the long-term outcome can be restricted. Knowledge of the effect of surgical treatment on formation of symptomatic heterotopic ossification in polytrauma is sparse. Therefore, we test the effects of surgical treatment (plate osteosynthesis or intramedullary nailing) on the formation of heterotopic ossification in the multiple trauma patient.</p> <p>Methods</p> <p>We retrospectively analysed prospectively documented data of blunt multiple trauma patients with long bone fractures which were treated at our level-1 trauma centre between 1997 and 2005. Patients were distributed to 2 groups: Patients treated by intramedullary nails (group IMN) or plate osteosynthesis (group PLATE) were compared. The expression and extension of symptomatic heterotopic ossifications on 3-6 months follow-up x-rays in antero-posterior (ap) and lateral views were classified radiologically and the maximum expansion was measured in millimeter (mm). Additionally, ventilation time, prophylactic medication like indomethacine and incidence and correlation of head injuries were analysed.</p> <p>Results</p> <p>101 patients were included in our study, 79 men and 22 women. The fractures were treated by intramedullary nails (group IMN n = 50) or plate osteosynthesis (group PLATE n = 51). Significantly higher radiologic ossification classes were detected in group PLATE (2.9 ± 1.3) as compared to IMN (2.2 ± 1.1; p = 0.013). HO size in mm ap and lateral showed a tendency towards larger HOs in the PLATE group. Additionally PLATE group showed a higher rate of articular fractures (63% vs. 28% in IMN) while IMN demonstrated a higher rate of diaphyseal fractures (72% vs. 37% in PLATE; p = 0.003). Ventilation time, indomethacine and incidence of head injuries showed no significant difference between groups.</p> <p>Conclusion</p> <p>Fracture care with plate osteosynthesis in polytrauma patients is associated with larger formations of symptomatic heterotopic ossifications (HO) while intramedullary nailing was associated with a higher rate of remote HO. For future fracture care of multiply injured patients these facts may be considered by the responsible surgeon.</p

SONDERFORSCHUNGSBEREICH 426 „LIMBISCHE STRUKTUREN UND FUNKTIONEN“ IM ZENTRUM DES GEHIRNS

An das „Limbische System“ knüpfen viele jener ungelösten Fragen an, die von jeher als zentral für das Verständnis von Funktion und Dysfunktion des menschlichen Gehirns betrachtet werden. Hier sind molekularzelluläre Eigenschaften, lokale Organisationsformen, Systemfunktionen, die menschliche Empfindung und das Gedächtnis auf vielfältigste Art miteinander verknüpft, zu deren Erfassung interaktive und multidisziplinäre wissenschaftliche Ansätze mit unterschiedlichen Ebenen der Analyse in besonderer Weise geeignet sind

Liver transplantation in primary biliary cirrhosis: Risk assessment and 11-year follow-up

Background/Aims: Liver transplantation (LTx) is the only established treatment in patients with end-stage primary biliary cirrhosis (PBC). Although short-term survival after LTx in this group of patients is usually good, few data exist on the long-term survival. The optimal timing of transplantation is difficult. Thus, the aims of this study were to assess the long-term survival of patients with PBC after LTx and to identify potential predictive factors for a positive outcome. Methods: Survival of 28 patients with PBC who underwent LTx between 1985 and July 1999 in a single center was studied by Kaplan-Meier analysis and was compared to predicted survival without LTx using established prognostic models for PBC, the Mayo and European risk scores. Potential prognostic parameters obtained before LTx were tested for correlation to survival. Rates of bone fractures as markers of hepatic osteodystrophy were compared before and after LTx. Results: Median follow-up after LTx was 90 months with a maximum of 140 months. Actuarial survival of patients with PBC was 89% after 1, 5, and 10 years and was significantly better than estimated survival without LTx after 1-7 years as calculated by the Mayo and European risk scores. Of several parameters tested, only serum bilirubin and the prognostic scores, but no other liver function tests obtained immediately prior to transplantation were significantly correlated with survival after LTx. The duration of intensive care after LTx was not associated with any parameters obtained before LTx. Bone fractures were diagnosed in 43% of patients of whom the vast majority were osteopenic before LTx as determined by osteodensitometry. Conclusion: Longterm survival of a well-defined group of patients with PBC was excellent after LTx and was inversely correlated with preoperative serum bilirubin levels as well as Mayo and European risk scores. Copyright (C) 2000 S. Karger AG. Basel

Social Defeat: Impact on Fear Extinction and Amygdala-Prefrontal Cortical Theta Synchrony in 5-HTT Deficient Mice

Emotions, such as fear and anxiety, can be modulated by both environmental and genetic factors. One genetic factor is for example the genetically encoded variation of the serotonin transporter (5-HTT) expression. In this context, the 5-HTT plays a key role in the regulation of central 5-HT neurotransmission, which is critically involved in the physiological regulation of emotions including fear and anxiety. However, a systematic study which examines the combined influence of environmental and genetic factors on fear-related behavior and the underlying neurophysiological basis is missing. Therefore, in this study we used the 5-HTT-deficient mouse model for studying emotional dysregulation to evaluate consequences of genotype specific disruption of 5-HTT function and repeated social defeat for fear-related behaviors and corresponding neurophysiological activities in the lateral amygdala (LA) and infralimbic region of the medial prefrontal cortex (mPFC) in male 5-HTT wild-type (+/+), homo- (−/−) and heterozygous (+/−) mice. Naive males and experienced losers (generated in a resident-intruder paradigm) of all three genotypes, unilaterally equipped with recording electrodes in LA and mPFC, underwent a Pavlovian fear conditioning. Fear memory and extinction of conditioned fear was examined while recording neuronal activity simultaneously with fear-related behavior. Compared to naive 5-HTT+/+ and +/− mice, 5-HTT−/− mice showed impaired recall of extinction. In addition, 5-HTT−/− and +/− experienced losers showed delayed extinction learning and impaired recall of extinction. Impaired behavioral responses were accompanied by increased theta synchronization between the LA and mPFC during extinction learning in 5-HTT-/− and +/− losers. Furthermore, impaired extinction recall was accompanied with increased theta synchronization in 5-HTT−/− naive and in 5-HTT−/− and +/− loser mice. In conclusion, extinction learning and memory of conditioned fear can be modulated by both the 5-HTT gene activity and social experiences in adulthood, accompanied by corresponding alterations of the theta activity in the amygdala-prefrontal cortex network

Elective implant removal in the upper extremity: only symptomatic patients benefit

Purpose: Elective implant removal (IR) in the upper extremity remains controversial. Implants in the olecranon and clavicle are commonly removed for prominence, unlike in the distal radius. Patient-reported symptomatic cannot be verified, and nonspecific discomfort remains unquantified. In this study, indications and outcomes of IR at the clavicle, olecranon and distal radius were evaluated, with a focus on postoperative patient satisfaction. Materials and methods: In this retrospective, single-center cohort study, patients, who received elective IR of the clavicle, olecranon and distal radius were included. Patients were followed up at least six weeks after IR. Outcomes included patient satisfaction, symptom resolution, and complications. Results: One hundred and eighty-nine patients were included. Unspecific symptoms of discomfort were the most prevalent indication for IR (48.7%), followed by pain (29.6%) and objective limited range of motion (ROM) (7%). Pain and limited ROM combined was observed in 13.8%. Subjective benefit following IR was described in 54%. Patients with limited ROM (OR 4.7, p < 0.001) or pain (OR 4.1, p < 0.001) were more likely to experience alleviation of complaints. Patients with unspecific symptoms of discomfort, often did not report improvement. Major complications occurred in 2%. Refractures were detected at the clavicle (3.7%) and at the olecranon (2.5%). Minor complication rate was 5%. Conclusion: IR is a safe procedure in the upper extremity. Indications based on unspecific symptoms of discomfort have a significant lower rate of patient satisfaction postoperatively. Elective IR should be considered cautiously, if it is driven primarily by unspecific symptoms of discomfort. Patient education is relevant to prevent dissatisfying outcome

Two types of interneurons in the mouse lateral geniculate nucleus are characterized by different h-current density

Although hyperpolarization-activated cyclic nucleotide-gated cation (HCN) channels and the corresponding h-current (I(h)) have been shown to fundamentally shape the activity pattern in the thalamocortical network, little is known about their function in local circuit GABAergic interneurons (IN) of the dorsal part of the lateral geniculate nucleus (dLGN). By combining electrophysiological, molecular biological, immunohistochemical and cluster analysis, we characterized the properties of I(h) and the expression profile of HCN channels in IN. Passive and active electrophysiological properties of IN differed. Two subclasses of IN were resolved by unsupervised cluster analysis. Small cells were characterized by depolarized resting membrane potentials (RMP), stronger anomalous rectification, higher firing frequency of faster action potentials (APs), appearance of rebound bursting, and higher I(h) current density compared to the large IN. The depolarization exerted by sustained HCN channel activity facilitated neuronal firing. In addition to cyclic nucleotides, I(h) in IN was modulated by PIP(2) probably based on the abundant expression of the HCN3 isoform. Furthermore, only IN with larger cell diameters expressed neuronal nitric oxide synthase (nNOS). It is discussed that I(h) in IN is modulated by neurotransmitters present in the thalamus and that the specific properties of I(h) in these cells closely reflect their modulatory options

Trochanteric fracture pattern is associated with increased risk for nonunion independent of open or closed reduction technique

PURPOSE Soft tissue injury and soft tissue injury as risk factors for nonunion following trochanteric femur fractures (TFF) are marginally investigated. The aim of this study was to identify risk factors for impaired fracture healing in geriatric trauma patients with TFF following surgical treatment with a femoral nail. METHODS This retrospective cohort study included geriatric trauma patients (aged > 70 years) with TFF who were treated with femoral nailing. Fractures were classified according to AO/OTA. Nonunion was defined as lack of callus-formation after 6 months, material breakage, and requirement of revision surgery. Risk factors for nonunion included variables of clinical interest (injury pattern, demographics, comorbidities), as well as type of approach (open versus closed) and were assessed with uni- and multivariate regression analyses. RESULTS This study included 225 geriatric trauma patients. Nonunion was significantly more frequently following AO/OTA 31A3 fractures (N = 10, 23.3%) compared with AO/OTA type 31A2 (N = 6, 6.9%) or AO/OTA 31A1 (N = 3, 3.2%, p < 0.001). Type 31A3 fractures had an increased risk for nonunion compared with type 31A1 (OR 10.3 95%CI 2.2 to 48.9, p = 0.003). Open reduction was not associated with increased risk for nonunion (OR 0.9, 95%CI 0.1 to 6.1. p = 0.942) as was not the use of cerclage (OR 1.0, 95%CI 0.2 to 6.5, p = 0.995). Factors such as osteoporosis, polytrauma or diabetes were not associated with delayed union or nonunion. CONCLUSION The fracture morphology of TFF is an independent risk factor for nonunion in geriatric patients. The reduction technique is not associated with increased risk for nonunion, despite increased soft tissue damage following open reduction