Journal of Rehabilitation Medicine 51-6 | Page 62

J Rehabil Med 2019; 51: 456–463 ORIGINAL REPORT CONCURRENT VALIDITY AND RELIABILITY OF A LOW-COST GAIT ANALYSIS SYSTEM FOR ASSESSMENT OF SPATIOTEMPORAL GAIT PARAMETERS Maijke VAN BLOEMENDAAL, MSc 1,2 , Anita BEELEN, PhD 1,2 , Rob F. M. KLEISSEN, PhD 3 , Alexander C. H. GEURTS, PhD 4 , Frans NOLLET, PhD 2 and Sicco A. BUS, PhD 2 From the 1 Merem Medical Rehabilitation, Hilversum, 2 Amsterdam UMC, University of Amsterdam, Department of Rehabilitation, Amsterdam Movement Sciences, Meibergdreef 9, Amsterdam, 3 Saxion University of Applied Sciences, Research Group Mechatronics, Enschede, and 4 Donders Centre for Brain, Cognition and Behaviour, Radboud University Medical Centre, Department of Rehabilitation, Nijmegen, The Netherlands Objective: To determine the concurrent validity and reliability of a low-cost spatiotemporal gait analysis system for clinical use in rehabilitation medicine. Design: Cross-sectional study. Subjects: Thirty-three healthy adults. Methods: The spatiotemporal gait analysis system consists of a video camera placed perpendicular to a 10-m walkway and calibrated for spatial reference. The conditions evaluated in this study were: bare- foot walking at comfortable and slow speed, toe and shod walking using a stationary camera setup and barefoot walking at comfortable speed using a mo- ving camera setup. The GAITRite® was used as re- ference. Results: High intraclass correlation coefficients (ICC≥ 0.97; 95% lower limit confidence intervals (95% CIs) ≥ 0.77) were found between systems for step and stride length, and step, stance and stride time, across setups and conditions. Standard error of measurement and Bland-Altman repeatability co- efficients were ≤ 2.4% and ≤ 6.3%, respectively. A minimum of 4 footsteps was required to obtain ICC >0.90 and coefficient of variation < 10%. For dou- ble support and swing time, ICCs were generally low (ICC≥ 0.21). Inter-rater reliability was excellent for step length, step and stance time (ICC≥ 0.94; lower limit 95% CIs ≥ 0.86). Conclusion: The spatiotemporal gait analysis system is valid and reliable for assessing spatiotemporal pa- rameters in different walking conditions. However, the validity of double support and swing time could not be confirmed. Key words: spatio-temporal analysis; gait; video recording; motion capture; reproducibility of results. Accepted Apr 25, 2019; Epub ahead of print May 10, 2019 J Rehabil Med 2019; 51: 456–463 Correspondence address: Maijke van Bloemendaal, Merem Medical Rehabilitation, Soestdijkerstraatweg 129, NL-1213 VX Hilversum, The Netherlands. E-mail: [email protected] G ait deviations are among the most commonly reported impairments in persons with a variety of neurological and musculoskeletal conditions (1–7). Evaluation of the effectiveness of interventions targe- ting gait requires sensitive and objective assessment of gait characteristics (8). Gait speed is the outcome most LAY ABSTRACT Gait parameters, such as step length and step time, al- low the quantification of gait deviations in persons with various diseases. Treatment can be customized and eva- luated based on these parameters. However, few low- cost, easily applicable systems are available for clinical settings to accurately measure gait parameters. A low- cost spatiotemporal gait analysis system was developed and this study evaluated its accuracy and reliability. The spatiotemporal gait analysis system consists of a ca- mera placed perpendicular to the walkway, which can be used stationary or moved manually along a parallel rail system to capture multiple strides of an individual during a single walk. Thirty-three healthy adults com- pleted trials of barefoot, toe and shod walking. These adults were simultaneously recorded using an electronic walkway, the GAITRite®, for comparison. The results showed that the spatiotemporal gait analysis system is an accurate and reliable system to assess step and stride length, step, stance, and stride time, but not to assess double support and swing time. often used in clinical practice, and commonly assessed with timed walking tests, such as the 10-m and 6-min walk test, using a designated track and stopwatch. However, these methods are limited for assessing other spatial and temporal parameters that are considered important to properly evaluate gait, such as step length and step time and derivative parameters such as gait symmetry (8–11). The validity of simple measurement methods, such as the stopwatch-footfall count method to assess step length, has not been confirmed (12). Clinical evaluation of these spatiotemporal characte- ristics is essential for identifying and understanding gait deviations, guiding clinical decision-making, customizing treatment, monitoring individual progress, and proving treatment benefits (1–6). Valid and reliable systems assessing spatiotemporal gait parameters include 3-dimensional motion cap- ture systems, and electronic walkways, such as the GAITRite® system (13–18). However, these systems are relatively costly and, regarding the 3-dimensional systems, too sophisticated for measuring spatiotempo- ral variables in a clinical setting. In case of electronic walkways, there may be practical issues, such as with restricting the subjects to walk within the relatively This is an open access article under the CC BY-NC license. www.medicaljournals.se/jrm doi: 10.2340/16501977-2559 Journal Compilation © 2019 Foundation of Rehabilitation Information. ISSN 1650-1977