Outcome of conservatively treated occipital condylar fractures – A retrospective study

Introduction: Occipital condyle fracture (OCF) is rare. It may, however, pose a serious threat to the patient due to destabilization of the craniocervical junction. Correct diagnosis and effective treatment are essential to prevent long-term complications. The aim of this study was to retrospectively investigate our current treatment program with focus on the functional outcome. Diagnosis and classification systems were evaluated for their usefulness in the clinical practice. Materials and Methods: We retrospectively reviewed all patients treated conservatively for an occipital condylar fracture from 2010 to 2015 at our department. Fracture classifications were performed according to three established systems. The patients were followed up with clinical examination and plain radiographs at weeks 2, 6, and 12 with the addition of a dynamic flexion-extension X-ray at week 14. Results: Totally 24 patients met the inclusion criteria. One was lost to follow-up and two ended treatment before completing the full treatment program due to a clinical decision. Fracture displacement was neither detected nor was any neurological deficits observed. Most patients were pain free after 6 weeks. After 14 weeks' treatment, two patients still had neck pain; the rest were pain free. Conclusions: Our data suggest that twelve weeks' conservative treatment is not necessary for unilateral OCFs without atlanto-occipital dissociation (AOD). We recommend 6 weeks of conservative treatment, with clinical control and flexion-extension radiographs before ending treatment. Plain radiography is of limited value in the clinical control of this fracture type. Anderson and Montesano and Tuli et al. classification systems fulfill an academic role. We found the classification system by Mueller et al. to be more helpful in everyday clinical practice

Modulator effects of interleukin-1beta and tumor necrosis factor-alpha on AMPA-induced excitotoxicity in mouse organotypic hippocampal slice cultures

The inflammatory cytokines interleukin-1\u2424 and tumor necrosis factor-\u2423 (TNF-\u2423) have been identified as mediators of several forms of neurodegeneration in the brain. However, they can produce either deleterious or beneficial effects on neuronal function. We investigated the effects of these cytokines on neuronal death caused by exposure of mouse organotypic hippocampal slice cultures to toxic concen- trations of AMPA. Either potentiation of excitotoxicity or neuroprotection was observed, depending on the concentration of the cytokines and the timing of exposure. A relatively high concentration of mouse recombinant TNF-\u2423 (10 ng/ml) enhanced excitotoxicity when the cultures were simultaneously exposed to AMPA and to this cytokine. Decreasing the concentration of TNF-\u2423 to 1 ng/ml resulted in neuroprotection against AMPA-induced neuronal death independently on the application protocol. By using TNF-\u2423 receptor (TNFR) knock-out mice, we demonstrated that the potentiation of AMPA-induced toxicity by TNF-\u2423 involves TNF receptor-1, whereas the neuroprotective effect is mediated by TNF receptor-2. AMPA exposure was associated with activation and proliferation of microglia as assessed by macrophage antigen-1 and bromodeoxyuridine immunohistochemistry, suggesting a functional recruitment of cytokine- producing cells at sites of neurodegeneration. Together, these findings are relevant for understanding the role of proinflammatory cytokines and microglia activation in acute and chronic excitotoxic condition

A brain slice culture model for studies of endogenous and exogenous precursor cell migration in the rostral migratory stream.

The rostral migratory stream (RMS) is the main pathway by which newly born subventricular zone (SVZ) cells reach the olfactory bulb (OB) in rodents. This migration has been well studied in vivo, but an organotypic in vitro model would facilitate more experimental investigations. Here we introduce a slice culture preparation of the rat forebrain including en suite the rostral part of the lateral ventricle, the RMS and the OB. The preparation was validated with regard to endogenous cell proliferation and migration by tracking bromodeoxyuridine (BrdU)-labelled cells in newly established and 3 and 6 week old cultures. For testing the migratory abilities of exogenous precursor cells, rat SVZ neurospheres and human neural (HNS1 cells) and mesenchymal (hMSC-TERT) stem cell lines were micrografted to the rostral SVZ of 1 and 7 day old cultures. Two weeks later graft derivatives were identified by immunohistochemical staining for human nuclei (HNS1/hMSC-TERT cells) and BrdU (HNS1 cells/neurospheres). Numerous HNS1 cells and BrdU-positive neurosphere cells were found in the RMS. Having reached the OB, subpopulations of the cells expressed the astroglial markers glial fibrillary acidic protein/hAM and the neuronal markers NeuN/tyrosine hydroxylase. Interestingly, the hMSC-TERT cells remained at the implantation site, demonstrating a diversity in migratory capability of different precursor cells. In conclusion, the RMS in rat forebrain slice cultures retains its ability to support migration of endogenous and exogenous neural precursors, making the cultures highly feasible for studies of conditions and factors regulating cell migration.This research was supported by the Danish MRC (J. No. 22-02-0150/22-02-0008), the Danish Centre for Stem Cell Research (J. No. 2052-01-0045) and as part of the European Science Foundation EUROCORES Programme EuroSTELLS, by funds from the European Commission Sixth Framework Programme (contract no. ERAS-CT-2003-980409). Work at the AMS group was supported by grants from the European Union (QLK3-CT-2001-02120), and Spanish Ministry of Science and Technology (MCYT SAF2001-1038-C02-02).Peer reviewe