Assessing lower limb position sense in stroke using the gradient discrimination test (GradDT™) and step-height discrimination test (StepDT™): a reliability and validity study

Abstract

Purpose: To evaluate the psychometric properties of two novel tests of lower limb position sense. Methods: Our newly developed tests assess discrimination thresholds of underfoot slope and step height perception using a two alternative forced choice approach. Stroke participants (n=32) and age matched controls (n=32) were tested. Inter-and intra-rater reliability and agreement, sensitivity and specificity, discriminant and convergent validity were evaluated. Results: Intra-rater reliability for both variants of the gradient discrimination test was excellent: intraclass correlation coefficients (ICC) =0.91 and 0.89. The step height discrimination test had excellent intra-rater reliability and agreement: ICC=0.95. Inter-rater reliability was also excellent in both tests (ICC= 0.85-0.93). Discriminant validity was demonstrated with significant differences in test performance between stroke and control participants (p<0.001). Our novel tests did not significantly correlate with the proprioceptive component of the Erasmus modified Nottingham Sensory Assessment. Receiver Operating Characteristic curve analysis indicated both novel tests to have greater sensitivity and specificity than the proprioceptive component of the Erasmus modified Nottingham Sensory Assessment in predicting the presence of self-reported sensory impairments. Functional Reach Test, 10 metre walk test, Centre of Pressure measurement and reported falls showed significant and moderate to strong correlations with novel test performance (r=0.40-0.60); the Erasmus modified Nottingham Sensory Assessment did not. Conclusion(s): Our novel, functionally oriented tests of lower limb position sense are reliable, valid and feasible for use in an ambulatory chronic stroke and elderly population.

Lower Limb Somatosensory Discrimination Is Impaired in People With Parkinson's Disease: Novel Assessment and Associations With Balance, Gait, and Falls

“…The GradDT evaluates sensory–perceptual ability to discriminate underfoot surface gradient or slope during standing. It has been described previously and shown to be reliable and valid in a stroke population . It uses a 2–alternative forced choice paradigm, in which 2 differing sloping platforms, a base and a comparator, are mentally compared (discriminated).…”

“…The StepDT uses the 2–alternative forced choice paradigm approach as detailed previously and has been described and psychometrically evaluated previously in stroke . This test assesses an individual's ability to discriminate the height of a step, through lower limb position sense, without visual feedback.…”

“…In response to the perceived shortcomings of the existing clinical measures, we developed the following 3 novel and functionally oriented tests of somatosensory discrimination: the Foot Roughness Discrimination Test (FoRDT), the Step Height Discrimination Test (StepDT), and the Gradient Discrimination Test (GradDT). These functionally oriented tests have been described and evaluated previously in a stroke population, showing superior psychometric properties to the clinically feasible and psychometrically robust sensory measure, the EmNSA . To date, however, our novel tests have not been evaluated in people with PD.…”

Impacts of Stroke on Muscle Perceptions and Relationships with the Motor and Functional Performance of the Lower Extremities

“…Recent studies also reported that perception impairment worsens over time in stroke patients [ 13 , 14 ], and 25–75% of such patients require assistance to perform daily activities [ 15 , 16 ]. Therefore, appropriate measurements that evaluate deficits in muscle perceptions using active joint reproduction tests in ankle movements are crucial and could provide true reflections of functional performances of the ankle joint during daily activities in post-stroke patients [ 17 ].…”

Die Rolle der Somatosensorik beim motorischen Lernen

“…Eine besondere Bedeutung in der Verarbeitung sen sorischer Information wird dabei dem Thalamus zugespro chen, der als Schaltstation zwischen afferenten Leitungs bahnen und der Großhirnrinde gilt [16]. [6,8,9]. Bevor eine Testung durchgeführt wird, soll te aber nicht nur klar sein, welche der oben genannten Sinnesmodalitäten man adressiert, sondern auch, welcher Aspekt der jeweiligen Sinnesmodalität untersucht werden soll.…”