40 research outputs found
Complications in ankle fracture surgery
Peer reviewe
Amputation following internal fixation of an ankle fracture via the posterolateral approach - a case report
Peer reviewe
Excitation spectra in crystal plasticity
Plastically deforming crystals exhibit scale-free fluctuations that are
similar to those observed in driven disordered elastic systems close to
depinning, but the nature of the yielding critical point is still debated.
Here, we study the marginal stability of ensembles of dislocations and compute
their excitation spectrum in two and three dimensions. Our results show the
presence of a singularity in the distribution of {\it excitation stresses},
i.e., the stress needed to make a localized region unstable, that is remarkably
similar to the one measured in amorphous plasticity and spin glasses. These
results allow us to understand recent observations of extended criticality in
bursty crystal plasticity and explain how they originate from the presence of a
pseudogap in the excitation spectrum.Comment: 5 pages, 4 figures, to appear in Phys. Rev. Let
Quenched pinning and collective dislocation dynamics
Several experiments show that crystalline solids deform in a bursty and intermittent fashion. Power-law distributed strain bursts in compression experiments of micron-sized samples, and acoustic emission energies from larger-scale specimens, are the key signatures of the underlying critical-like collective dislocation dynamics - a phenomenon that has also been seen in discrete dislocation dynamics (DDD) simulations. Here we show, by performing large-scale two-dimensional DDD simulations, that the character of the dislocation avalanche dynamics changes upon addition of sufficiently strong randomly distributed quenched pinning centres, present e.g. in many alloys as immobile solute atoms. For intermediate pinning strength, our results adhere to the scaling picture of depinning transitions, in contrast to pure systems where dislocation jamming dominates the avalanche dynamics. Still stronger disorder quenches the critical behaviour entirely.Peer reviewe
Avalanches in Wood Compression
Wood is a multiscale material exhibiting a complex viscoplastic response. We study avalanches in small wood samples in compression. “Woodquakes” measured by acoustic emission are surprisingly similar to earthquakes and crackling noise in rocks and laboratory tests on brittle materials. Both the distributions of event energies and of waiting (silent) times follow power laws. The stress-strain response exhibits clear signatures of localization of deformation to “weak spots” or softwood layers, as identified using digital image correlation. Even though material structure-dependent localization takes place, the avalanche behavior remains scale-free.Peer reviewe
The role of outpatient visit after operative treatment of ankle fractures
It is a common practice that patients have a scheduled follow-up visit with radiographs following ankle fracture surgery. The aim of this study was to evaluate whether an early outpatient visit ( A change in treatment plan was observed in 9.8% of operatively treated ankle fracture patients. The mean age of the patients was 48 years and the mean follow-up time was 64 months. Of the changes in treatment plan, 91% were exclusively due to clinical findings such as infection. Only three of 878 patients required a change in their treatment plan based merely on the findings of the radiographs taken at the outpatient visit. Only 37% of the patients requiring a change in their postoperative management had solicited an unanticipated visit before the scheduled outpatient visit due to clinical problems such as infection or a cast-related issue. Our study showed that every tenth operatively treated ankle fracture patient requires a change in their treatment plan due to a clinical problem such as infection or a cast-related issue. Although at hospital discharge all patients are provided with written instructions on where to contact if problems related to the operated ankle emerge, only one third of the patients are aware of the clinically alarming symptoms and seek care when problems present. Our findings do not support obtaining routine radiographs at the early outpatient visit in an ankle fracture patient without clinical signs of a complication. (C) 2016 Published by Elsevier Ltd.Peer reviewe
Traumatic Rupture and Herniation of the Peroneus Tertius Muscle Leading to Compartment Syndrome and Entrapment of the Superficial Peroneal Nerve : A Case Report
We present a patient with compartment syndrome and entrapment of the superficial peroneal nerve due to a direct hit to the lateral part of the right lower extremity. The diagnosis of evolving compartment syndrome was made without delay and the patient was quickly taken to the operating theater. Intraoperatively, the entrapment of the superficial peroneal nerve caused by rupture and herniation of the peroneus tertius muscle was surprisingly observed at the site, where the nerve pierces the anterior compartment. The nerve was successfully released in conjunction with fasciotomies of the anterior and lateral compartments. Meticulous diagnosis of compartment syndrome is critical to prevent ischemic injury to muscles and nerves. Recognition of anatomy and anatomical variations is important to prevent iatrogenic injury in unusual circumstances.Peer reviewe
Nilkan avomurtumat : esiintyvyys, hoito ja komplikaatiot
Open ankle fractures are rare injuries with a high incidence of wound complications and infection related morbidity. The aim of this study was to evaluate the demographic characteristics, outcomes, and complications of patients treated for open ankle fractures at a level-1 trauma center from 2006 to 2011. We identified 137 open ankle fractures from a cohort of 3041 consecutive operatively treated ankle fractures. The mean age of patients was 60 years and 56% were women. Only 20% of the fractures were the result of high-energy trauma. Most of the fractures were Weber type B with a medial sided wound. Immediate internal fixation was performed in 82% of patients, and the wound was primarily closed in the majority of cases (80%). The incidence of deep infection and postoperative wound necrosis was 17% and 18%, respectively. Older patients did not have an increased risk of complications. The results showed that younger patients are more likely to suffer an open ankle fracture resulting from high-energy trauma, leading to more complications and subsequent increased resource utilization
Onko nilkkamurtuman leikkaushoidon jälkeinen kahden viikon kontrollikäynti tarpeen?
English abstrac