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Objective: Quadriceps dysfunction has been suggested as a complication after medial patellofemoral ligament (MPFL) reconstruction. The purpose of this study was to investigate changes in knee extensor strength before and after MPFL reconstruction.

Methods: Twenty patients who underwent MPFL reconstruction for unilateral recurrent patellar dislocation (18 females and 2 males; mean age 20.8 ± 7.6 years) were examined. The peak isometric torque at 60° and 90° of knee flexion and isokinetic knee extensor strength at speeds of 60°/s and 90°/s in operated and non-operated legs were measured using a dynamometer preoperatively and 6 months, 1 year, and 2 years postoperatively. The following parameters were evaluated: (1) body weight-adjusted muscle strength, (2) improvement index (post-/preoperative value × 100) (%), and (3) extensor strength ratio (operated/non-operated value × 100) (%).

Results: The mean knee extensor strength in both operated and non-operated legs significantly increased 2 years after surgery compared with that before surgery. At 2 years postoperatively, the improvement indexes of the isometric knee extensor strength at 60° and 90° and of the isokinetic knee extensor strength at 60°/s and 90°/s were 237%, 192%, 318%, and 186%, respectively, in the operated legs and 144%, 124%, 140%, and 140%, respectively, in the non-operated legs. At 2 years postoperatively, the mean isometric knee extensor strength ratios at 60° and 90° and the isokinetic knee extensor strength ratios at 60°/s and 180°/s were 81%, 84%, 81%, and 82%, respectively.

Conclusions: Knee extensor strength was improved in most patients after MPFL reconstruction, at least compared with that before surgery, although an approximately 20% deficit against the non-operated legs remained even 2 years after surgery.  相似文献   

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BackgroundWhether coronary plaque characteristics assessed in coronary computed tomography angiography (CCTA) in association with the coronary artery calcium score (CACS) have predictive value for coronary events is unclear. We aimed to examine the predictive value of the CACS and plaque characteristics for the occurrence of coronary events.MethodsAmong 2802 patients who were analyzed in the PREDICT registry, 2083 with suspected coronary artery disease (CAD) were studied using post hoc analysis. High-risk plaques were defined as having ≥2 adverse characteristics, such as low computed tomographic attenuation, positive remodeling, spotty calcification, and napkin-ring sign. An adjudicative composite of coronary events (cardiac death, nonfatal acute coronary syndrome, and coronary revascularization ≥3 months after indexed CCTA) were analyzed.ResultsSeventy-three (3.5%) patients had coronary events and 313 (15.0%) had high-risk plaques. Multivariate Cox proportional hazard analysis showed that high-risk plaques remained an independent predictor of coronary events (adjusted hazard ratio [HR] 1.95, 95% confidence interval [CI] 1.13–3.34, P ?= ?0.0154), as well as the log-transformed CACS (adjusted HR 1.24, 95% CI 1.11–1.39, P ?= ?0.0002) and the presence of obstructive stenosis (adjusted HR 5.63, 95% CI 3.22–10.12, P 0.0001). In subgroup analyses, high-risk plaques were independently predictive only in the low CACS class (<100).ConclusionThis study shows that assessment of adverse features by coronary plaque imaging independently predicts coronary events in patients with suspected CAD and a low CACS. Our findings suggest that the clinical value of high-risk plaques to CACS and stenosis assessment appears marginal.  相似文献   
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Background

Poststroke gait disorders negatively impact activities of daily living. Rehabilitation for stroke patients is aimed at improving their walking ability, balance, and quality of life. Robot-assisted gait training (RAGT) is associated with an increased number of task-specific exercises, which may benefit poststroke motor learning. We investigated the effects of RAGT using Stride Management Assist (SMA, which increases walk ratio by inducing hip-joint flexion and extension) in subacute stroke patients with hemiplegia.

Methods

We conducted a single center, open-label randomized controlled trial in hemiplegia patients who experienced a first ever stroke and were admitted to the convalescent rehabilitation ward. A total of 41 were divided into the control (20 patients) and experimental group (21 patients). A 10-day, conventional gait training program was carried out for the control group; and RAGT with SMA was used for the experimental group. The maximum walking speed and other gait parameters were compared preintervention and postintervention. The intergroup differences in the improvement ratio were compared using an intention-to-treat analysis.

Results

Ten-day intervention was completed by 36 patients. There was no difference between the 2 groups regarding gait parameters at intervention initiation. The improvement ratio of the maximum walking speed was significantly higher for the experimental group. Significant improvements were observed postintervention for maximum walking speed, paralysis-side step length, symmetry, and cadence in the experimental group. No adverse events attributable to the SMA were observed.

Conclusions

Ten days of RAGT with the SMA was effective for improving gait disorders of subacute stroke patients.  相似文献   
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Analysis of anticancer immunity aids in assessing the prognosis of patients with breast cancer. From 250 operated breast cancers, we focused on serum levels of C‐C motif chemokine ligand 5 (CCL5), which is involved in cancer immune reactions. Serum levels of CCL5 were measured using a cytometric bead‐based immunoassay kit and CCL5 expression in cancer cells was determined using immunohistochemical staining. In addition, mRNA in cancer and stromal cells was analyzed by microdissection and comparison with the public dataset. Disease‐free survival (DFS) of patients with high CCL5 levels (cut‐off, 13.87 ng/mL; n = 192) was significantly better than those with low CCL5 levels (n = 58; hazard ratio, 0.20; 95% confidence interval, 0.10‐0.39; P < .0001). An improved overall survival was observed in patients with high CCL5 levels compared to those with low CCL5 levels (P = .024). On the contrary, high immunohistochemical expression of CCL5 in cancer cells was significantly associated with decreased DFS. As serum CCL5 levels did not correlate with CCL5 expression in cancer cells and the relative expression of mRNA CCL5 was elevated in stromal cells in relation to cancer cells, serum CCL5 might be derived not from cancer cells, but from stromal cells. Expression of CCL5 in serum, but not in cancer cells, might contribute to improved patient prognosis mediating through not only immune reaction, but through other mechanisms. Determination of circulating CCL5 levels could be useful for predicting patient prognosis.  相似文献   
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Osteogenesis imperfecta (OI) was originally considered a connective tissue disorder, primarily involving type 1 collagen. It is characterized by numerous skeletal and extraskeletal defects, including bone fragility, multiple fractures, blue sclerae, hearing deficits, skin and ligament laxity, and dentinogenesis imperfecta (DI). The authors describe a 24-year-old Japanese man with OI and DI who had an ossifying fibroma of the mandible. Segmental resection was performed, and the mandible was reconstructed by distraction osteogenesis with the transport segment technique. This is the first report to describe a patient with OI undergoing mandibular reconstruction with bone transport, to the authors' knowledge.  相似文献   
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