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Background

There are numerous reports and evidences to suggest that exercise therapy is effective for knee osteoarthritis (knee OA). However, there is a lack of sufficient research concerning the factors influencing its application and effectiveness. The purposes of this study were to evaluate effects of the mode of treatment delivery on the improvement of symptoms in knee OA, and to analyze potential risk factors affecting improvement after exercise therapies.

Methods

The 209 women applicants diagnosed with knee OA were randomly allocated into either a group performing group exercise in a class or a group performing home exercise. The 90 min exercise program was performed under the guidance of physiotherapists as a group exercise therapy. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) of the subjects of both groups before and after intervention was compared to examine the effect of exercise therapy. In addition, body mass index, knee range of motion (ROM), the femorotibial angle from radiographs, OA severity from Kellgren–Lawrence grade, and meniscus abnormality and subchondral bone marrow lesions from MRI findings were statistically analyzed as factors that may affect exercise therapy.

Results

A significantly greater improvement in WOMAC was observed in the subjects of group exercise (81 subjects) as compared with the subjects of home exercise (122 subjects). There was a significantly high proportion of subjects with knee flexion contracture among the subjects participating in group exercise that showed only minor symptom improvement (p < 0.05). In addition, exercise therapy proved to be highly effective for subjects with limited quadriceps muscle strength (p < 0.05).

Conclusions

When prescribing exercise therapy for knee OA, evaluation of a subject’s ROM and muscle strength is important in deciding whether to commence exercise therapy and what type of exercise therapy to apply; it is also important in predicting the effect of exercise therapy.  相似文献   
215.

Purpose

To explore the possibility of targeted biopsy (TBx) using transrectal ultrasound (US) with perflubutane microbubbles, we studied the findings of different cancerous tissue imaging modalities and evaluated needle biopsy in prostate cancer (PCa) using contrast-enhanced US (CEUS) in a multicenter clinical trial.

Methods

Seventy-one patients undergoing prostate biopsy received intravenous injection of perflubutane microbubbles (Sonazoid®). We evaluated and compared images obtained by CEUS. The safety observation period was 2 days after contrast administration.

Results

Among the 30 patients with cancer, one or more sites with findings suggestive of cancer in CEUS were detected in 23 patients (32.4%) by TBx. Although 22 patients had positive cores of cancer by systematic biopsy (SBx), 8 patients had positive cores of cancer in TBx alone (11.3%). There was a significant difference in cancer detection rate by TBx between two cohorts with PSA < 10 ng/mL (22.9%) and PSA ≥ 10 ng/mL (52.2%) (P < 0.02). Close observation of various CEUS findings with Sonazoid® enabled targeting of cancerous areas, and consequently, a significant difference (P < 0.05) in the detection rate of cancer was recognized in the transition zone (TZ): SBx; 21/120 (17.5%) and TBx; 17/55 (30.9%). The incidence of adverse events was 6.7% and that of adverse reactions was 4%.

Conclusions

CEUS with Sonazoid® improved the detection rate of PCa by visualizing cancerous lesions. More detailed examination of CEUS images provided efficient characterization especially in the TZ area. TBx according to this procedure is expected to enable a lower number of biopsies and more accurate diagnosis of PCa.  相似文献   
216.
Magnetic resonance imaging (MRI) has been recognized as the most accurate imaging modality for the detection of diabetic foot osteomyelitis. However, how accurately MRI displays the extent of diabetic foot osteomyelitis in the presence of ischemia is still unclear. We retrospectively compared the preoperative MRI findings with the results of histopathologic examinations of resected bones and studied the efficacy of MRI in the diagnosis of diabetic foot osteomyelitis of different etiologies. A total 104 bones from 18 foot ulcers in 16 diabetic patients (10 men and 6 women; age range 42 to 84 years) treated by surgical intervention from 2008 to 2012 was examined. In 8 neuropathic ulcers, 29 bones were accurately diagnosed in detail using MRI, even those with severe soft tissue infection. Of 75 bones in 10 ischemic ulcers, only 7 bones evaluated by MRI after revascularization were diagnosed accurately; the other 68 could not be diagnosed because of unclear or equivocal MRI findings. On histopathologic examination, all the bones were found to be infected through the bone cortex by the surrounding infected soft tissue, not directly by articulation. Overall, preoperative MRI is effective in the diagnosis of neuropathic ulcers, but less so of ischemic ones.  相似文献   
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ObjectiveWhile the importance of cortical structure quantification is increasingly underscored by recent literature, conventional analysis techniques obscure potentially important regional variations in cortical structure. The objective of this study was to characterize the spatial variability in cortical geometry and microstructure at the distal radius and tibia using high resolution peripheral quantitative computed tomography (HR-pQCT). We show that spatially-resolved analysis is able to identify cortical sub-regions with increased sensitivity to the effects of gender and aging.MethodsHR-pQCT scans of 146 volunteers (92 female/54 male) spanning a wide range of ages (20–78 years) were analyzed. For each subject, radius and tibia scans were obtained using a clinical HR-pQCT system. Measures describing geometry (cortical bone thickness (Ct.Th)), microstructure (porosity (Ct.Po), pore diameter (Ct.Po.Dm), and pore size heterogeneity (Ct.Po.Dm SD)), and cortical bone density were calculated from the image data. Biomechanical parameters describing load and stress distribution were calculated using linear finite element analysis. Cortical quadrants were defined based on anatomic axes to quantify regional parameter variation. Subjects were categorized by gender, and age, and menopausal status for analysis.ResultsSignificant regional variation was found in all geometric and microstructural parameters in both the radius and tibia. In general, the radius showed more pronounced and significant variations in all parameters as compared with the tibia. At both sites, Ct.Po displayed the greatest regional variations. Correlation coefficients for Ct.Po and Ct.Th with respect to load and stress distribution provided evidence of an association between regional cortical structure and biomechanics in the tibia. Comparing women to men, differences in Ct.Po were most pronounced in the anterior quadrant of the radius (36% lower in women (p < 0.01)) and the posterior quadrant of the tibia (27% lower in women (p < 0.01)). Comparing elderly to young women, differences in Ct.Po were most pronounced in the lateral quadrant of the radius (328% higher in elderly women (p < 0.001)) and the anterior quadrant of the tibia (433% higher in elderly women (p < 0.001)). Comparing elderly to young men, the most pronounced age differences were found in the anterior radius (205% higher in elderly men, (p < 0.001)) and the anterior tibia (190% higher in elderly men (p < 0.01)). All subregional Ct.Po differences provided greater sensitivity to gender and age effects than those based on the global means.ConclusionThese results show significant regional variation in all geometric and microarchitectural parameters studied in both the radius and tibia. Quantification of region-specific parameters provided increased sensitivity in the analysis of age- and gender-related differences, in many cases providing statistically significant differentiation of groups where conventional global analysis failed to detect differences. These results suggest that regional analysis may be important in studies of disease and therapeutic effects, particularly where microstructural parameters based on global analyses have thus far failed to identify a response in bone quality.  相似文献   
219.
Introduction: It is generally believed that a shorter stimulus duration is less painful in nerve conduction studies (NCS). We investigated whether a shorter duration stimulus is actually less painful when the same physiological effect, such as supramaximal stimulation, is achieved in motor NCS. Methods: The tibial nerve was stimulated at the ankle in 14 control subjects and the median nerve at the wrist in 20 subjects. Two stimulations of different durations were given blindly, and each subject was asked to report which was more painful. Results: A 0.2‐ms‐duration stimulus was significantly less painful than those with longer or shorter durations for the tibial nerve. For the median nerve, the 0.05‐ and 0.2‐ms durations were equally less painful than a 1‐ms‐duration stimulus. Conclusions: As a common duration for motor NCS, 0.2 ms seems appropriate, because the tibial nerve stimulation was more painful than the median nerve stimulation. Muscle Nerve, 2013  相似文献   
220.

Object

The brain temperature at rest is determined by the balance between heat produced by cerebral energy turnover, which is identical to cerebral metabolism, and heat that is removed, primarily by cerebral blood flow. The present study investigated whether brain temperature measured by proton magnetic resonance (MR) spectroscopy can detect cerebral hemodynamic impairment in patients with arteriovenous malformations (AVMs) as shown by single photon emission computed tomography (SPECT).

Methods

Brain temperature, cerebral blood flow, and cerebrovascular reactivity were measured using proton MR spectroscopy and SPECT in five healthy volunteers and six patients with AVMs. Regions of interest were selected adjacent to the AVMs and in the corresponding contralateral region.

Results

Brain temperature around AVMs was calculated in all subjects using MR spectroscopy. The mean brain temperature in volunteers was 37.1 ± 0.41 °C. A significant correlation was observed between brain temperature ratio (affected side/contralateral side) and cerebrovascular reactivity ratio (affected side/contralateral side) (r = −0.82, p = 0.0480).

Conclusion

Brain temperature measured by proton MR spectroscopy can detect cerebral hemodynamic impairment in patients with AVMs. Further investigations regarding the relationships between brain temperature and clinical feature in patients with AVMs are needed.  相似文献   
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