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Medial tibial stress syndrome (MTSS) is one of the most common lower leg injuries in sporting populations. It accounts for between 6 and 16% of all running injuries, and up to 53% of lower leg injuries in military recruits. Various treatment modalities are available with varying degrees of success. In recalcitrant cases, surgery is often the only option. To evaluate whether ultrasound-guided injection of 15% dextrose for treatment of recalcitrant MTSS decreases pain and facilitates a return to desired activity levels for those who may otherwise be considering surgery or giving up the sport. The study design was a prospective consecutive case series involving eighteen patients: fifteen male and three female; (mean age = 31.2 years) with recalcitrant MTSS. They were referred from sports injury clinics across the UK, having failed all available conservative treatment. An ultrasound-guided sub-periosteal injection of 15% dextrose was administered by the same clinician (NP) along the length of the symptomatic area. Typically, 1 mL of solution was injected per cm of the symptomatic area. Pain was assessed using a 10-cm visual analog scale (VAS) at baseline, short-term, medium-term (mean 18 weeks), and long-term (mean 52 weeks) follow-up. Symptom resolution and return to activity were measured using a Likert scale at medium and long-term follow-up. Statistical analyses were performed using SPSS for Mac version 19.0.0 (IBM, New York, NY, US). The Shapiro-Wilk test was used to evaluate the normality of the distribution of data. Friedman’s non-parametric test was used to compare the within-patient treatment response over time. Post-hoc Wilcoxon signed-rank tests with Bonferroni corrections were performed to determine VAS average pain response to treatment over five paired periods. Patients reported a significant (p < 0.01) reduction in median VAS pain score at medium and long-term follow-up compared to baseline. Median improvement per patient was 4.5/10. Patients rated their condition as ‘much improved’ at medium-term follow-up and the median return to sports score was ‘returned to desired but not pre-injury level’ at medium-term and long-term follow-up. No adverse events were reported. Ultrasound-guided 15% dextrose prolotherapy injection has a significant medium-term effect on pain in MTSS. This benefit may be maintained long-term; however, more robust trials are required to validate these findings in the absence of controls. Clinicians should consider the use of ultrasound-guided injection of 15% dextrose as a viable treatment option to reduce pain and aid return to activity for patients with recalcitrant MTSS.  相似文献   
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BackgroudCurrent evidence supports the use of cemented hemiarthroplasty for treatment of intracapsular femoral neck fractures since it is associated with a lower risk of implant-related complications. However, many medical centers employ the cementless technique for the frail elderly population because it is faster and has lower cardiovascular risks and perioperative mortality. This observational study reports the outcomes of cementless bipolar hemiarthroplasty for intracapsular femoral neck fractures in patients aged 80 years and older.MethodsA total of 424 patients (female, 77.1%) with a mean age of 86.9 years were operated for intracapsular femoral neck fractures between January 2009 and December 2017. Of those, 66.7% had an American Society of Anaesthesiologists (ASA) score of 3 or more. All operations were performed with the posterolateral surgical approach and all patients received a cementless stem. Intraoperative and perioperative values and in-hospital outcomes were evaluated, and clinical and radiographical follow-up was done at 40 days, 90 days, and when possible between 5 months and 12 months postoperatively. Multivariate analysis was performed to evaluate if there were factors affecting mortality.ResultsThe mean operative time was 50 minutes. There were no deaths intraoperatively. Intraoperative periprosthetic fractures occurred in 2.1% of the cases with 66.7% of them fixed through cerclage wires intraoperatively. The median length of hospitalization was 11 days (interquartile range, 8.75–15) and 2.4% of patients died while in hospital after surgery. Approximately 91.5% of patients presented with perioperative anemia. Only 1.9% of the complications were related to the implant, 62.5% of which were dislocations. More than 90% of patients were ambulatory either autonomously or with support at each follow-up assessment. Age, male sex, and higher ASA score were related to increased mortality.ConclusionsDespite some limitations, this observational study underlines that a cementless femoral stem of modern design can give good clinical outcomes, thus being an appropriate solution especially for the frail elderly.  相似文献   
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During the last century, the reduction of birth and all-cause mortality rates have resulted in an increase in the life expectancy and the proportion of the elderly population in many countries. For example, elderly women represent more than 16% and elderly men comprise more than 12% of the population in Italy. The health consequences of these demographic shifts in population is important, because older people experience reductions in some physiologic functions and in increased incidence of chronic, mainly cardiovascular, diseases. Data derived from a survey of men between the ages of 71 and 91 years, who are the survivors of the original rural samples of the Italian section of the Seven Countries Study, show the large contribution of cardiovascular diseases to the long list of chronic conditions. The indicators of self-sufficiency, dementia, and of the self-perception of poor health proved much more common among subjects with cardiovascular diseases than in those with other chronic conditions.  相似文献   
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A male infant, born from consanguineous parents, suffered from birth with a progressive neuromuscular disorder characterized by psychomotor delay, hypotonia, muscle weakness and wasting, deep-tendon areflexia and spastic posture. High levels of lactic acid in blood and cerebrospinal fluid suggested a mitochondrial respiratory chain defect. Muscle biopsy revealed raggedred and cytochromec oxidase-negative fibres, lipid accumulation and dystrophic changes. Multiple defects of respiratory complexes were detected in muscle homogenate, but cultured fibroblasts, myoblasts and myotubes were normal. Southern blot analysis showed markedly reduced levels of mitochondrial DNA (mtDNA) in muscle, while lymphocytes, fibroblasts and muscle precursor cells were normal. Neither depletion of mtDNA nor abnormalities of the respiratory complexes were observed in innervated muscle fibres cultured for as long as 4 months. No mutations were observed in two candidate nuclear genes,mtTFA andmtSSB, retro-transcribed, amplified and sequenced from the proband's mRNA. Sequence analysis of the mtDNA D-loop and of the origin of replication of the mtDNA light strand failed to identify potentially pathogenic mutations of these replicative elements in the proband's muscle mtDNA. Our findings indicate that mtDNA depletion is due to a nuclear encoded gene and suggest that the abnormality underlying defective mtDNA propagation must occur after muscle differentiation in vivo.  相似文献   
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Neuronal activity was established in the auditory pathways in relation to behavioural response and cognitive information processing during a sensory-motor acoustic learning. Rats were trained in three consecutive phases. The first phase was an association between an auditory stimulus and a food reward; the second phase a simple discrimination between two sounds of different frequency components, and the third phase a more complex discrimination involving both spectral and spatial sound dimensions. Auditory stimuli were bursts of complex sounds lasting 500 ms. Neuronal activity related to the behaviourally relevant stimuli was established in 20 "learning" rats undergoing this protocol, which were progressively sacrificed at the beginning, middle and end of each phase. For comparison, activity was also established in four "control" rats exposed to the same stimuli delivered pseudo-randomly, thus carrying no behavioural meaning. Neuronal activity was assessed immunocytochemically using the functional marker Fos. To establish a baseline, two rats were unexposed to controlled acoustic stimulation ("unstimulated" rats). In the superior olivary complex (SOC), inferior colliculus (IC) and medial geniculate body (MGB), the number of Fos-like immunopositive cells was comparable in "learning" and "control" animals, but higher than in the "unstimulated" rats. In the auditory cortex (AC), most prominently in the secondary area Te2, the number of Fos-like positive cells differed between "learning" and "control" rats, suggesting that the auditory cortical areas may be involved in the encoding of the behavioural significance of the acoustic stimuli.  相似文献   
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