U. Gopaul1,2, D. Laver3, L. Carey4, T.A. Matyas4, P. van Vliet5, R. Callister3
1University of Newcastle, School of Health Sciences, Newcastle, Australia, 2University of Mauritius, Department of Health Sciences, Reduit, Mauritius, 3University of Newcastle, School of Biomedical Sciences and Pharmacy, Newcastle, Australia, 4The Florey Institute of Neuroscience and Mental Health, Neurorehabilitation and Recovery Group, Melbourne, Australia, 5University of Newcastle, School of Humanities and Social Science, Newcastle, Australia
Background: Instantaneous peak grip strength is widely used to characterise muscle weakness after stroke. Sustained grasp is essential for functional tasks in daily life. Sensor-based devices can record pressure or force over time during grasping and therefore offer a more comprehensive approach to quantifying grip strength during sustained contractions. The reliability of grip strength using the TactArray device has not been investigated.
Purpose: To investigate the reliability and the concurrent validity of maximal tactile pressures and forces of a sustained grasp task using the TactArray device in healthy people and in people with stroke.
Methods: Healthy participants (n=18, mean age: 62.2 ± 9.9 years) and participants with stroke (n=11, mean age: 64.1 ± 9.0 years) performed three trials of sustained maximal grasp over 8 seconds. Both hands were tested in within-day (two sessions, one hour apart) and between-day (two sessions, one week apart) sessions, with vision and without vision. Measures of maximal tactile pressures and forces were measured for the complete grasp duration (8s) and for the plateau phase (5s). Measures of maximal tactile pressures and forces were reported using the highest value among the three repetitions, the mean of two repetitions, and the mean of three repetitions. Reliability was determined using changes in mean, coefficients of variation and intraclass correlation coefficients (ICCs). Pearson correlation coefficients were used to evaluate concurrent validity.
Results: In healthy individuals, changes in mean were very good (range:-0.09-3.11%), coefficients of variation acceptable (range:9.85-12.95%) and ICCs were good (range:0.59-0.84) for maximal tactile pressures using highest value among the three repetitions and the mean of three repetitions for the complete grasp duration (8s) and for the plateau phase (5s) in the dominant hand with and without vision for within-day and between-day sessions. In the non-dominant hand, changes in mean were very good to good (range:-1.48-6.22%) and coefficients of variation were good to acceptable (range:8.08-12.82%) and ICCs very good to good (range:0.89-0.92) without vision for within-day and between-day sessions. In people with stroke, changes in mean were good (range:-2.02- -7.18%), coefficients of variation were good to acceptable (range:9.52-14.72%) and ICCs very good (range:0.90-0.97) for maximal tactile pressures using Pres(8s)avg3 in the affected hand with and without vision for within-day sessions and without vision for between-day sessions. In the less affected hand, changes in mean were very good (range:0.00-5.04%), coefficients of variations were acceptable (range:11.73-15.92%) and ICCs were good to very good (range:0.88-0.93) for maximal tactile pressures using Pres(5s)avg3 and Pres(8s)avg3 in between-day session with and without vision. Maximal tactile pressures had moderate to large correlations (r=0.4-0.6) with grip strength in health individuals and people with stroke.
Conclusion(s): The TactArray device demonstrates satisfactory reliability for measures of maximal tactile pressures during a sustained grasp for within-day and between-day testing sessions using an average of three trials with or without vision in healthy people and those with stroke. Validity was satisfactory with grip strength in both hands.
Implications: The TactArray provides reliable intra-day and inter-day measures of maximal tactile pressures in healthy people and those with stroke. The TactArray provides a comprehensive evaluation of grasp performance over time.
Funding, acknowledgements: University of Newcastle
Keywords: Reliability, TactArray, sustained grasp
Topic: Neurology: stroke
Did this work require ethics approval? Yes
Institution: University of Newcastle, Australia
Committee: Human Research Ethics Committee
Ethics number: Reference no. H-2015–0052
All authors, affiliations and abstracts have been published as submitted.
