Reliability and validity of the sideways step test and its correlation with motor function after stroke

[Purpose] This study investigated the intra-rater, inter-rater and test-retest reliability of the sideways step test (SST), its correlation with other indicators of stroke-specific impairment, and the cut-off count best discriminating subjects with stroke from their healthy counterparts. [Subjects and Methods] Forty-three subjects with chronic stroke and 41 healthy subjects older than 50 years participated in this study. The SST was administered along with the Fugl-Meyer motor assessment for the lower extremities (FMA-LE), the five-times sit to stand (5TSTS) test, the Berg Balance Scale (BBS), the movement velocity (MVL) by the limits of stability (LOS) test, the ten-metre walk (10mW) test, the timed “Up and Go” (TUG) test and the Activities-specific Balance Confidence (ABC) scale. [Results] The SST showed good to excellent intra-rater, inter-rater and test-retest reliability. The SST counts correlated with 5TSTS times, 10mW times, TUG times, and the FMA-LE and BBS scores. SST counts of 11 for the paretic leg and 14 for the non-paretic leg were found to distinguish the healthy adults from subjects with stroke. [Conclusion] The sideways step test is a reliable clinical test, which correlates with the functional strength, gait speed, and functional balance of people with chronic stroke.Key words: Balance, Stroke, Rehabilitation     

Effects of chemical denervation with 6-hydroxydopamine on myocardial responsiveness to isoproterenol in rabbits

This study examined the hypothesis that chemical denervation with 6-hydroxydopamine (6-OHDA) would increase myocardial responsiveness to isoproterenol. Five days previously, 15 New Zealand white rabbits were given 60 mg/kg 6-OHDA intravenously. Fifteen control rabbits received vehicle. Hemodynamic, coronary blood flow (CBF), and cardiac output measurements were obtained before and during isoproterenol infusion (0.5 g/kg/min for 15 min). Norepinephrine tissue content, -adrenoceptor number (Bmax) and affinity (Kd), cyclic AMP content and cyclic AMP-phosphodiesterase (PDE) activity were measured in the subepicardium (EPI) and subendocardium (ENDO). Myocardial norepinephrine content was significantly decreased from 1263±292 (EPI) and 874±221 ng/g tissue (ENDO) in the control to 148 ±33 (EPI) and 90±45 ng/g tissue (ENDO) in the denervated group. There were no significant changes in cyclic AMP-PDE activity of Bmax and Kd of -adrenoceptors. Cyclic AMP content was similar at baseline, but controls had a significantly larger increase (123–155 %) during isoproterenol infusion when compared to the denervated group (27–37%). The denervated animals showed a smaller increase in cardiac output during isoproterenol infusion (from 203±30 to 235±26 ml/min), when compared to the control animals (from 135±18 to 216±42 ml/min). Baseline CBF was significantly higher in the EPI but not ENDO of the denervated group (185±20 ml/ 100 g/min in EPI and 150±8 in ENDO) compared to the control group (108±13 in EPI and 133±17 in ENDO). The relative increase in CBF during isoproterenol infusion was smaller in the denervated group (44–45%) than the control group (107–109%). Isoproterenol infusions of 0.1 and 2.5 g/kg/min showed similarly depressed coronary blood flow responses in denervated animals. Thus, the chemically denervated animals did not have -adrenoceptor upregulation, exhibited a lesser increase in cyclic AMP with isoproterenol, and had a reduced functinal and coronary blood flow response to isoproterenol. This occurred without any significant change in -adrenoceptor number or affinity, or in cyclic AMP-phosphodiesterase activity, indicating there may be receptor uncoupling or other changes in the signal transduction pathway.     

An MR-Conditional High-Torque Pneumatic Stepper Motor for MRI-Guided and Robot-Assisted Intervention

Magnetic resonance imaging allows for visualizing detailed pathological and morphological changes of soft tissue. MR-conditional actuations have been widely investigated for development of image-guided and robot-assisted surgical devices under the Magnetic resonance imaging (MRI). This paper presents a simple design of MR-conditional stepper motor which can provide precise and high-torque actuation without adversely affecting the MR image quality. This stepper motor consists of two MR-conditional pneumatic cylinders and the corresponding supporting structures. Alternating the pressurized air can drive the motor to rotate each step in 3.6° with the motor coupled to a planetary gearbox. Experimental studies were conducted to validate its dynamics performance. Maximum 800 mN m output torque is achieved. The motor accuracy independently varied by two factors: motor operating speed and step size, was also investigated. The motor was tested within a 3T Siemens MRI scanner (MAGNETOM Skyra, Siemens Medical Solutions, Erlangen, Germany) and a 3T GE MRI scanner (GE SignaHDx, GE Healthcare, Milwaukee, WI, USA). The image artifact and the signal-to-noise ratio (SNR) were evaluated for study of its MRI compliancy. The results show that the presented pneumatic stepper motor generated 2.35% SNR reduction in MR images. No observable artifact was presented besides the motor body itself. The proposed motor test also demonstrates a standard to evaluate the pneumatic motor capability for later incorporation with motorized devices used under MRI.     

Atrial fibrillation

The management of atrial fibrillation has evolved greatly in the past few years, and many areas have had substantial advances or developments. Recognition of the limitations of aspirin and the availability of new oral anticoagulant drugs that overcome the inherent drawbacks associated with warfarin will enable widespread application of effective thromboprophylaxis with oral anticoagulants. The emphasis on stroke risk stratification has shifted towards identification of so-called truly low-risk patients with atrial fibrillation who do not need antithrombotic therapy, whereas oral anticoagulation therapy should be considered in patients with one or more risk factors for stroke. New antiarrhythmic drugs, such as dronedarone and vernakalant, have provided some additional opportunities for rhythm control in atrial fibrillation. However, the management of the disorder is increasingly driven by symptoms. The availability of non-pharmacological approaches, such as ablation, has allowed additional options for the management of atrial fibrillation in patients who are unsuitable for or intolerant of drug approaches.     

The effectiveness of an integrated pain management program for older persons and staff in nursing homes

This study examined the effects of an 8-week integrated pain management program (IPMP) on enhancing the knowledge and attitude toward pain management among staff; and improving the pain, quality of life, physical and psychosocial functions, and use of non-drug therapies for the elderly in nursing homes. Nursing home staff (N=147) and residents (N=535) were recruited from ten nursing homes. Nursing homes were randomly assigned into an experimental group (N=296) with IPMP or control group (N=239) without IPMP. The IPMP consisted of pain education for staff and physical exercise and multisensory stimulation art and craft therapy for residents. Data were collected before and after the IPMP. The staff demonstrated a significant improvement in knowledge and attitude to pain management, with the survey score increasing from 8.46±3.74 to 19.43±4.07 (p<0.001). Among the residents, 74% had experienced pain within the previous 6 months, with pain intensity of 4.10±2.20. Those in the experimental group showed a significantly better reduction in pain scores than the control group, from 4.19±2.25 to 2.67±2.08 (p<0.001). Group differences were also found in psychological well-being, including happiness, loneliness, life satisfaction and depression (p<0.05), and the use of non-drug methods (p<0.05). These results suggested that IPMP is beneficial for staff, and is effective in reducing geriatric pain and negative impacts. Management support and staff involvement in the program are important for its long-term continuation.