Pre-Congress Workshops
The following Pre-Congress Workshops will be offered prior to the Congress. Registration for these workshops can be completed within the online Congress registration process.
Gait variability - Pearls and Precautions
Date: Sunday, June 24
Time: 14:30 – 16:30
Cost: $75
Presentations:
Jennifer S. Brach
Jeff M. Hausdorff
Rolf Moe-Nilssen
Description:
Gait is characterized by repetitive cycles, but also by variability. Balance control requirements, adaptability to a changing environment, cognitive function and measurement error are just a few of the factors that have been associated with gait variability. Variability may be measured in a number of ways including temporal and spatial footfall fluctuations, stride-to-stride changes in trunk accelerations, and joint kinematics and kinetics. Conventional statistical metrics like the standard deviation and coefficient of variation have been applied to quantify gait variability along with metrics derived from dynamical systems approaches. In spite of a rapid increase in the number of scientific papers on gait variability, consensus has not been reached on the appropriateness and interpretation of measures and approaches, nor is it known to what degree variability measures are related to each other.
The presenters will summarize different perspectives on the study and interpretation of gait variability and lead a discussion about what's known and unknown about this aspect of gait. Examples of key questions that will be addressed include:
- Is variability an independent gait feature?
- Can it be used as a sensitive bio-marker?
Ample time will be set aside for questions and discussion. The workshop will serve as a teaser on an issue that will no doubt engage presenters and the audience throughout the conference.
GAITRite - Innovative Applications for Functional Gait and Balance Measures
Date: Sunday, June 24
Time: 10:00 - 12:00
Cost: $75
Description:
Please stay tuned for workshop description.
Motor Unit Firing Behavior Revealed by Decomposition of the sEMG Signal
Date: Sunday, June 24
Time: 10:00 - 12:00
Cost: $75
Presentation:
Carlo J de Luca, NeuroMuscular Research Center, Boston University, Boston, MA, USA; Delsys Inc, Boston MA
Description:
During the past three decades, with the collaboration of numerous colleagues, we have developed a technology for extracting the firing instances and shapes of the motor unit action potentials from the EMG signal for the purpose of investigating mechanisms used by the CNS and PNS to control motor units when generating force. The technology uses sophisticated Artificial Intelligence concepts, to decompose the surface EMG signals into their constituent individual action potential trains. Presently the technology can identify the firings of up to 75 active motor units with an average accuracy of 95% and at times reaching 97% in contractions up to 100% MVC. Most importantly, we have also developed tests to assess the accuracy of all the identified firing instances (1,2,3) and to assess the validity and unbiased behavior of the technology (4).
We will discuss the general details of the technology and will provide an overview of the decomposition algorithms, along with the procedure for calculating the accuracy of the identified firing instances. A demonstration of the technology, its use, and a description of the identified motor unit firing parameters will be provided.
This novel technology provides a host of parameters related to the firing behavior of motor units such as: firing interval statistics, firing rate, recruitment and de-recruitment force thresholds, and the shape of the action potential. These parameters are commonly used to describe the firing behavior of the motor units and to observe if it is modified under a variety of conditions such as: exercise, fatigue, movement disorders, training, etc.
The technology has been used by us (3, 4) to study the characteristics of motor unit control and by others (5,6) to study the motor unit firing behavior during fatigue. It has been used to initiate investigations into clinical applications (7,8). Various other studies are in progress.
- De Luca CJ, Adam A, Wotiz R, Gilmore LD, and Nawab SH. Decomposition of surface EMG signals. Journal of Neurophysiology, 96: 1646-1657, 2006.
- Nawab SH, Chang SS, and De Luca CJ. High-yield decomposition of surface EMG signals. Clinical Neurophysiology, 121(10):1602-1615, 2010.
- De Luca CJ and Contessa P. Hierarchical control of motor units in voluntary contraction. Journal of Neurophysiology, 107: 178-195, 2012.
- De Luca CJ and Hostage EC. Relationship between firing rate and recruitment threshold of motoneurons in voluntary isometric contractions. Journal of Neurophysiology, 104: 1034-1046, 2010.
- Beck TW, DeFreitas JM, Stock MS, and Dillon MA. Effects of resistance training on force steadiness and common drive. Muscle & Nerve, 43(2) 245-250, 2011.
- Beck TW, DeFreitas JM, Stock MS. The Effects of a Resistance Training Program on Average Motor Unit Firing Rates. Clinical Kinesiology, 65(1), 2011.
- Richards J, Selfe J. EMG Decomposition of Vastus Medialis and Vastus Lateralis in normal subjects and patellofemoral patients: A new way of assessing the balance of muscle function? International Patellofemoral Research Retreat, Ghent 31 August - September 2011.
- Suresh N, Li X, Zhou P, Rymer WZ. Examination of Motor Unit Control Properties in Stroke Survivors Using Surface EMG Decomposition: A Preliminary Report. The 33rd Annual International Conference of the IEEE EMBS, Boston, September 2011.
The Farseeing Perspective: "How to measure and share real life fall data"
Date: Sunday, June 24
Time: 13:00 - 16:00
Cost: No charge
Chairs:
Clemens Becker, MD
Lorenzo Chiari, PhD
Presentations:
Dr. Clemens Becker | Aims of the workshop |
Dr. Jochen Klenk | The limits of simulating falls |
Fabio Bagala | Algorithm testing and development |
Prof. Stephen Robinovich | Real life falls captured on video |
Dr. Wiebren Ziljstra | Fall prediction with BFS |
Prof. Kamiar Aminian | Dynamic balance in real world situation for fall prediction |
Prof. Lorenzo Chiari | BFS sites and types and the detection fall signals |
Round table:
Main findings of a consensus process for a meta-data base of real falls
Clemens Becker, Lorenzo Chiari
Description:
The main objective of the workshop is to share and consolidate and knowledge about real life fall signals. Instrumental to this objective is the sharing on findings on real life fall data captured with video and body-fixed sensor technology. This includes agreement on a dynamic fall risk model. The workshop will also present and discuss the findings of a consensus building process on the construction of a data base on real falls including the following aims:
- Define a data format and build up a meta-database to collect a reasonable number of falls
- Build up a network of experts in this field willing to share knowledge and data
- Collect data and signals through the monitoring of high-risk subjects and fit elderly people
- Develop signal processing methods and novel algorithms for the assessment of daily living activities and of health status
- Define an evidence-based fall risk model using advanced data mining and reasoning techniques.
- Identify a strategy for the sustainability of the repository