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Background

Home‐exercise is commonly prescribed for rehabilitation of the shoulder following injury. There is a lack of technology available to monitor if the patient performs the exercises as prescribed.

Purpose

The purpose of this study was to investigate the validity of using three dimensional (3D) gyroscope data recorded with the Bandcizer™ sensor to differentiate between three elastic band exercises performed in the shoulder joint: abduction, flexion, and external rotation.

Design

Concurrent validity study.

Methods

This study was performed over two phases. In the first phase, 20 subjects performed three sets of 10 of shoulder abduction, external rotation and flexion exercises with a Thera‐Band mounted with a Bandcizer, while supervised by a physical therapist. The Bandcizer has an inbuilt three‐dimensional gyroscope, capable of measuring angular rotation. Gyroscope data were analyzed in Matlab, and a one‐way ANOVA was used to test for significant differences between each of the three exercises. An algorithm was then created in Matlab based on the exercise‐data from the gyroscope, to enable differentiation between the three shoulder exercises. Twenty new subjects were then recruited to cross‐validate the algorithm and investigate if the algorithm could differentiate between the three different shoulder exercises.

Results

A blinded assessor using the Matlab algorithm could correctly identify 56 out of 60 exercise sets. The kappa agreement for the three exercises ranged between 0.86‐0.91.

Conclusion

The ability to differentiate between the home exercises performed by patients after shoulder injury has great implications for future clinical practice and research. When home exercises are the treatments‐of‐choice, clinicians will be able to quantify if the patient performed the exercise as intended. Further research should be aimed at investigating the feasibility of using the Bandcizer™ in a home‐based environment.

Word count

2429

Level of Evidence

2  相似文献   
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BACKGROUND: Whether to include only those patients who have not had prior hypertension treatment in clinical trials of left ventricular (LV) mass reduction is controversial. Accordingly, our aim was to study the relationship between prior treatment and both baseline and 1-year echocardiographic LV mass in subjects enrolled in the Losartan Intervention For Endpoint reduction (LIFE) study. METHODS: We studied clinical and baseline echocardiographic data on 960 patients with electrocardiographically confirmed left ventricular hypertrophy enrolled in the electrocardiographic substudy of the LIFE study, 847 of whom had LV mass remeasured after 1 year of blinded treatment. The majority (75%) of these patients had prior medical treatment for hypertension. RESULTS: In multivariable regression analysis, controlling for age, sex, blood pressure (BP), body mass index, and indices of pump and myocardial function, prior antihypertensive treatment was not associated with either greater LV mass or relative wall thickness on the baseline study. Moreover, there was no significant difference between the 637 subjects who were previously treated and the 210 who were not treated with regard to the mean reduction in systolic or diastolic pressures (-25 +/- 17 v -24 +/- -16 and -13 +/- 9 mm Hg v -12 +/- 9 mm Hg), LV mass (-27 +/- 38 v -29 +/- 34 g), or LV mass/body surface area (-14 +/- 20 v -15 +/- 18 g/m(2)), all P >.05. CONCLUSIONS: Prior treatment is not associated with either greater LV mass or greater relative wall thickness when age, body mass index, sex, systolic BP, heart rate, or indices of LV volume load and systolic function are taken into account. In addition, prior treatment is not associated with lesser degrees of LV mass reduction. For design of future clinical trials, restriction of inclusion criteria to only previously untreated patients does not appear to be necessary when the selection criterion is electrocardiographically determined left ventricular hypertrophy.  相似文献   
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There is limited information about the in-hospital plasma profile of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in patients with non-ST-elevation acute coronary syndrome (NSTACS) and furthermore, the prognostic influence of the timing of NT-proBNP measurements in NSTACS is unsettled. These subject matters are elucidated in this study composed of 455 patients with NSTACS (symptoms <24 h). NT-proBNP was measured at 0, 6, 12, 24, 36, 48, 72 and 96 h following admission. Any death was registered at follow-up (median: 2.3 years). The study demonstrated a monophasic profile of the plasma NT-proBNP values, reaching a maximum at 6 hours, and it showed an independent prognostic significance of NT-proBNP irrespective of the sampling time. Risk prediction by NT-proBNP was improved by combining the baseline measurement and one value taken between 24 and 96 h (at 48 h, P<0.001). No additional prognostic information was provided by including more than one late in-hospital NT-proBNP value. Conclusions: The in-hospital NT-proBNP measurements exhibit a monophasic profile in patients with NSTACS and these values provide independent prognostic information as regards mortality irrespective of the sampling time. Moreover, risk prediction of NT-proBNP is strengthened by combining the admission measurement with an additional value during the hospitalization.  相似文献   
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Synthetic cannabinoids (SCs) are the most chemically diverse group of new psychoactive substances. This group has been associated with several intoxications, many with fatal outcomes. Although advancements have been achieved in pharmacology, metabolism, and detection of these compounds in recent years, these aspects are still unresolved for many SCs. The aim of this study was to investigate the in vitro potency of 14 indole‐ and indazole‐based SCs by applying a stable CB1 or CB2 receptor activation assay and correlating the activity with their structure. The half‐maximal effective concentration (EC50) of 5‐chloropentyl, 5‐bromopentyl, and 5‐iodopentyl JWH‐122 analogs varied from 74.1 to 283.7 nM for CB1 and 7.05 to 23.4 nM for CB2, where the addition of a chlorine atom enhanced the potency at CB1 compared with the bromo and iodo analogs. AM‐2201 was the most active at CB1 within this naphthoylindole family, with an EC50 of 23.5 nM but with the lowest efficacy (Emax 98.8%). Within the indole‐3‐carboxamide derivatives, 5F‐MDMB‐PICA was the most active compound, with a CB1/CB2 EC50 of 3.26/0.87 nM and an Emax around three times higher than JWH‐018. ADB‐FUBINACA was the most potent tested SC overall, with a CB1/CB2 EC50 of 0.69/0.59 nM, and an Emax around 3‐fold higher than that for JWH‐018 at CB1. The data obtained in this study confirm how small differences in the structure of SCs might lead to large differences in their activity, especially at CB1, which may be correlated with differences in their toxic effects in humans.  相似文献   
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