Current Research Projects
Fitts’ Law Using Lower Extremity Movement: A Performance Driven Outcome Measure for Degenerative Lumbar Spinal Stenosis
Steven Passmore, Valerie Pelleck, Alyson Gysel, Michael Johnson, Dean Kriellaars and Cheryl M. Glazebrook
Introduction: Objective outcome measures are lacking for the progression, impairment and management of degenerative lumbar spinal stenosis (LSS). Fitts’ Law is an established motor paradigm that may provide a novel approach to outcome measurement since task difficulty is easily manipulated, and performance on Fitts’ Law tasks are resistant to learning.
Methods: Participants with degenerative LSS (N=12) and healthy controls (N=12) performed pointing movements with their great toe to a series of squares that appeared on a touchscreen monitor. Three dimensional motion analysis recorded movement. Behavioural measures included reaction time and movement time (MT), kinematic performance measures were also recorded. The Health Research Ethics Board approved all protocols and procedures.
Results: Significant interactions for MT [F(5,110) = 3.17, p<.05] and kinematic variables time to peak velocity [F(5,110) = 5.51 p<.05] and peak velocity [F(5,110) = 9.61 p<.05 ] respectively revealed that the LSS group’s movements were more adversely impacted by increasing task ID.
Discussion: A traditional Fitts’ Law paradigm was replicated where movement times, and in this case kinematic variables, were slower with increased IDs (as defined by the target width and movement amplitude). Movement performance can be utilized as a tool to establish functional ability and quantify functional change in degenerative LSS patients.
Conclusion: A lower extremity Fitts’ Law task is useful in measuring differences between healthy and LSS populations. In the future it may be applied in LSS clinical intervention studies considering motor performance measurement as a quantitative outcome measure.
The Impact of Lumbar Spinal Stenosis on Lower Extremity Motor Control: Using movement to measure function
Steven R Passmore; Valerie Pelleck; Yasmine Amad; Erica Ramos; Michael Johnson; Cheryl M Glazebrook
Introduction: Activities of daily living create strain in degenerative lumbar spinal stenosis (LSS) patients, does treadmill walking? Replicating a recently established performance-based outcome measure, we explored strain in LSS patients.
Methods: LSS patients(N=16) and healthy controls(N=16) performed 2 blocks of great-toe pointing movements to a series of projected squares. Following block-one participants completed a 12-minute progressive exercise treadmill test (PETT). Pointing movements were analyzed using 3D motion analysis. Behavioural and kinematic measures evaluated performance. The Health Research Ethics Board approved all procedures.
Results: Both groups’ reaction times (RT) lengthened as task difficulty increased. An interaction revealed LSS patients were more adversely impacted F(3,372)=4.207;p=.006. The PETT facilitated RT for both groups, F(1,124)=5.105;p=0.026. Control participants were less variable in time to peak velocity post-strain, a benefit not shared by LSS patients, t(31)=2.149;p=0.040.
Discussion: Behavioural and kinematic variables replicated previous findings. LSS patients did not experience equal benefits of treadmill walking as controls. Both movement preparation and limb movement initiation variability were impacted in an LSS population post-strain.
Conclusion: A lower extremity movement task captured differences under strain between healthy and LSS populations. To enhance performance-based outcome measurement, future LSS clinical intervention studies may consider strain induction.
Current Graduate Student work
Focus of Attention During Skilled and Unskilled Putting [Pilot testing phase]
The wording of task instructions has been shown to affect the performance and learning of both novel and well practiced tasks. Numerous investigations have found improved results when utilizing an external focus of attention (the effects of a movement), compared to an internal focus of attention (the movement itself). Previous research has focused primarily on performance-based outcome measures. However, it is essential to look at other measures to understand the mechanism behind performance improvements. In this study, skilled and beginner golfers will participate in a golf putting task under four attentional focus conditions. The dependent variables of interest will be the accuracy of each putt, the kinematics of the club head and the neurophysiological activity of select upper and lower body muscles. It is anticipated that the results of this study will confirm previous knowledge on the topic, as well as further demonstrate the physiological effects of task instruction.