The past,present, and future of telemedicine for Parkinson's disease

Travel distance, growing disability, and uneven distribution of doctors limit access to care for most Parkinson's disease (PD) patients worldwide. Telemedicine, the use of telecommunications technology to deliver care at a distance, can help overcome these barriers. In this report, we describe the past, present, and likely future applications of telemedicine to PD. Historically, telemedicine has relied on expensive equipment to connect single patients to a specialist in pilot programs in wealthy nations. As the cost of video conferencing has plummeted, these efforts have expanded in scale and scope, now reaching larger parts of the world and extending the focus from care to training of remote providers. Policy, especially limited reimbursement, currently hinders the growth and adoption of these new care models. As these policies change and technology advances and spreads, the following will likely develop: integrated care networks that connect patients to a wide range of providers; education programs that support patients and health care providers; and new research applications that include remote monitoring and remote visits. Together, these developments will enable more individuals with PD to connect to care, increase access to expertise for patients and providers, and allow more‐extensive, less‐expensive participation in research. © 2014 International Parkinson and Movement Disorder Society     

A new method for muscle fatigue assessment: Online model identification techniques

Introduction: The purpose of this study was to propose a method that allows extraction of the current muscle state under electrically induced fatigue. Methods: The triceps surae muscle of 5 subjects paralyzed by spinal cord injury was fatigued by intermittent electrical stimulation (5 × 5 trains at 30 Hz ). Classical fatigue indices representing muscle contractile properties [peak twitch (Pt) and half‐relaxation time (HRT)] were assessed before and after each 5‐train series and were used to identify 2 relevant parameters (F_m, U_r) of a previously developed mathematical model using the Sigma‐Point Kalman Filter. Results: Pt declined significantly during the protocol, whereas HRT remained unchanged. Identification of the model parameters with experimental data yielded a model‐based fatigue assessment that gave a more stable evaluation of fatigue than classical parameters. Conclusions: This work reinforces clinical research by providing a tool that clinicians can use to monitor fatigue development during stimulation. Muscle Nerve 50: 556–563, 2014     

Botulinum toxin injection for post‐stroke spasticity

Introduction: The aim of this study was to evaluate test feasibility, validity, and reproducibility of the rate of force development scaling factor (RFD‐SF) for the hip muscles. Methods: Feasibility was assessed as the testing compliance, validity as the ability to compute the RFD‐SF from a linear regression, and reproducibility with a test–retest design in 20 healthy subjects. Reliability and agreement (reproducibility) were evaluated using intraclass correlation coefficient (ICC_3,1) and percent standard error of measurement (SEM), respectively. Results: The RFD‐SF testing protocol was completed successfully by all subjects, although the analysis had to be modified for hip rotators. Reliability was high (ICC_3,1 > 0.70) for all muscles except hip abductors (ICC_3,1 = 0.69) and internal rotators (ICC_3,1 = 0.58). Agreement was high for all muscles (SEM < 10%). Conclusions: Hip adductor, flexor, and external rotator RFD‐SF can be evaluated with confidence, provided the analysis is modified for external rotators, whereas hip abductor and internal rotator RFD‐SF assessment is not recommended. Muscle Nerve 50: 932–938, 2014     

Electrical impedance myography for the in vivo and ex vivo assessment of muscular dystrophy (mdx) mouse muscle

Introduction: Sensitive, non‐invasive techniques are needed that can provide biomarkers of disease status and the effects of therapy in muscular dystrophy. Methods: We evaluated electrical impedance myography (EIM) to serve in this role by studying 2‐month‐old and 18‐month‐old mdx and wild‐type (WT) animals (10 animals in each of 4 groups). Results: Marked differences were observed in EIM values between mdx and WT animals; the differences were more pronounced between the older age groups (e.g., reactance of 92.6 ±4.3 Ω for mdx animals vs. 130 ± 4.1 Ω for WT animals, P < 0.001). In addition, in vivo EIM parameters correlated significantly with the extent of connective tissue deposition in the mdx animals. Conclusions: EIM has the potential to serve as a valuable non‐invasive method for evaluating muscular dystrophy. It can be a useful biomarker to assist with therapeutic testing in both pre‐clinical and clinical studies. Muscle Nerve 49 : 829–835, 2014