A Study on Surgical Management of Unstable Pelvic Fractures

INTRODUCTION: Pelvic injuries are an important aspect of orthopaedic trauma, which are caused by high velocity injuries such as road traffic accidents and industrial accidents. The management, especially those of unstable pelvic ring injuries is complex and challenging to the orthopaedic surgeon. In this study, a brief and comprehensive review of the anatomy of the pelvis, biomechanics, the mechanism of different types of unstable injury and the classification are presented followed by the clinico radiological assessment of patients with pelvic injuries and their management by various surgical modalities. We have analyzed then the outcome of these unstable pelvic injuries with surgical management. AIM: The aim of this study is to analyze the results and functional outcome of the patients with unstable pelvic fractures who were managed by surgical treatment. MATERIALS AND METHODS: Our study is an analysis of 21 cases of unstable pelvic injuries (Type B and C) managed surgically by external fixation or open reduction and internal fixation. The study period extends from October 2004 to October 2006 and conducted at the Government General Hospital and Madras Medical College, Chennai, India. All the patients with stable pelvic ring injury (tile type A) were excluded from the study. Unstable pelvic injury patients, who died before surgical intervention (3 patients) and patients who couldn’t be operated for various reasons were excluded from the study. Recently operated patients with less than three months duration at the time of conclusion of this study were excluded. RESULTS: Twenty one patients with unstable pelvic fractures were treated surgically and analyzed with an average follow up of 8.7 months (range 3-16 months). Functional outcome of the survived patients were assessed using the pelvic outcome scale by Cole et al. It is based on a 40 point scale for pain, ambulation, work and activity status, clinical examination and radiographic appearance. Three patients died and two patients were lost for follow up. In one patient the functional outcome couldn’t be assessed due to associated injury. Out of 15 remaining patients, 12 had good, 2 had fair, and 1 patient had poor outcome. CONCLUSION: Despite better understanding of the personality of the acutely injured pelvis and modern aggressive treatment modalities, the mortality rate still remains high. Early aggressive but thoughtful management of the patients with unstable pelvic injuries is essential for maximizing the immediate survival and long term functional outcome. Periodic thorough clinical and radiological assessment is mandatory to identify any occult injury. The role of team approach with various specialists cannot be over emphasized. The degree of hemodynamic instability does not correlate with type of pelvic injury. Emergent external skeletal fixation alone is not sufficient to restore hemodynamic stability in all patients who fail to improve after initial resuscitation. Acute management of unstable pelvic injuries is challenging and techniques of safe internal fixation are demanding. Constant dedication to improvement is and must be the goal of pelvic surgeons

Development of cryogenic correlated light electron microscopy methods to study mechanisms of intracellular trafficking and their relationships to the secretory pathway

The application of cryogenic electron microscopy (cryo‐EM) to the study of cellular ultrastructure provides a resolution several orders of magnitude better than light microscopy. Although this approach is increasingly applied in situ, it suffers from limitations in our ability to target imaging to specific intracellular features including the subcellular localization of specific events of interest. Cryogenic correlated light and electron microscopy (cryo‐CLEM) helps to overcome this problem by spatially locating areas of interest inside cells using fluorescence from genetically tagged or stained cellular molecules and allows for the visualization of localized fluorescently‐tagged proteins down to the level of individual organelles. Here, we attempted to study the secretory pathway in a specialized mammalian cell line, insulin‐secreting INS‐1E cells, expressing genetically‐encoded fluorophores as a model system to develop a cryo‐CLEM methodology. We discovered that there are many bright sources of autofluorescence in frozen cells. Based on our initial observations and the current understanding in the field, we hypothesized that autofluorescence from endogenous cellular substrates exhibits a broader spectrum of fluorescence than the fluorescence range of our expressed fluorescent proteins. To test this, we developed a quantitative approach to discriminate between autofluorescence and the fluorescent signal from genetically‐encoded fluorophores by measuring fluorescent intensities across different bandwidths. To validate this new methodology, we visualized multiple fluorophore‐tagged organelle markers in our experimental cell system. We found that DsRed2‐cytochrome c oxidase and chromogranin A‐GFP proteins were targeted in INS‐1E cells to mitochondria and secretory granules by cryo‐CLEM, consistent with their respective well‐established intracellular localizations. Moreover, these fluorescent signals were clearly distinguishable from autofluorescence emanating from endogenous structures including insulin crystals and multilamellar bodies. Overall, our novel cryo‐CLEM methods open the door to the study of cellular phenomena and structures with a new degree of specificity

Search for Gravitational-wave Inspiral Signals Associated with Short Gamma-ray Bursts During LIGO's Fifth and Virgo's First Science Run

Progenitor scenarios for short gamma-ray bursts (short GRBs) include coalescenses of two neutron stars or a neutron star and black hole, which would necessarily be accompanied by the emission of strong gravitational waves. We present a search for these known gravitational-wave signatures in temporal and directional coincidence with 22 GRBs that had sufficient gravitational-wave data available in multiple instruments during LIGO's fifth science run, S5, and Virgo's first science run, VSR1. We find no statistically significant gravitational-wave candidates within a [ – 5, + 1) s window around the trigger time of any GRB. Using the Wilcoxon-Mann-Whitney U-test, we find no evidence for an excess of weak gravitational-wave signals in our sample of GRBs. We exclude neutron star-black hole progenitors to a median 90% confidence exclusion distance of 6.7 Mpc

First search for gravitational waves from the youngest known neutron star

We present a search for periodic gravitational waves from the neutron star in the supernova remnant Cassiopeia A. The search coherently analyzes data in a 12 day interval taken from the fifth science run of the Laser Interferometer Gravitational-Wave Observatory. It searches gravitational-wave frequencies from 100 to 300 Hz and covers a wide range of first and second frequency derivatives appropriate for the age of the remnant and for different spin-down mechanisms. No gravitational-wave signal was detected. Within the range of search frequencies, we set 95% confidence upper limits of (0.7–1.2) × 10^(−24) on the intrinsic gravitational-wave strain, (0.4–4) × 10^(−4) on the equatorial ellipticity of the neutron star, and 0.005–0.14 on the amplitude of r-mode oscillations of the neutron star. These direct upper limits beat indirect limits derived from energy conservation and enter the range of theoretical predictions involving crystalline exotic matter or runaway r-modes. This paper is also the first gravitational-wave search to present upper limits on the r-mode amplitude