Brian Horsak1, Barbara Pobatschnig2, Arnold Baca3, Susanne Greber-Platzer4, Alexandra Kreissl4, Stefan Nehrer5, Barbara Wondrasch6, Richard Crevenna7, Mohammad Keilani7, Andreas Kranzl2. 1. St. Pölten University of Applied Sciences, Department of Physiotherapy, Austria. Electronic address: brian.horsak@fhstp.ac.at. 2. Orthopedic Hospital Vienna-Speising, Laboratory of Gait and Movement Analysis, Austria. 3. University of Vienna, Department of Biomechanics, Kinesiology and Applied Computer Science, Austria. 4. Medical University of Vienna, Department of Pediatrics and Adolescent Medicine, Austria. 5. Danube University Krems, Centre for Regenerative Medicine and Orthopedics, Austria. 6. St. Pölten University of Applied Sciences, Department of Physiotherapy, Austria. 7. Medical University of Vienna, Department of Physical Medicine and Rehabilitation, Austria.
Abstract
INTRODUCTION: Three-dimensional gait analysis (3DGA) in obese populations is a difficult task due to a great amount of subcutaneous fat. This makes it more challenging to identify anatomical landmarks, thus leading to inconsistent marker placement. Therefore, the purpose of this study was to investigate the test-retest reliability for kinematic measurements of obese children and adolescents. METHODS: Nine males and two females with an age-based BMI above the 97th percentile (age: 14.6±2.6years, BMI: 33.4±4.4kg/m2) were administered to two 3DGA sessions. To quantify reliability of discrete parameters the intraclass correlation coefficient (ICC2,k), standard error of measurement (SEM) and minimal detectable change (MDC) were calculated. To quantify waveform similarity, the coefficient of multiple correlation (CMC) and the linear fit method (LFM) were used. RESULTS: From 28 kinematic parameters, 23 showed acceptable ICCs (≥0.70) and the remaining parameters demonstrated moderate values. These were peak hip extension during stance (0.58), mean pelvis rotation (0.60), mean anterior pelvic tilt (0.64), peak knee flexion during swing (0.67) and peak hip abduction during swing (0.69). The SEM was below 5° for all parameters. The MDC for the sagittal, frontal, and transversal plane were on average 7.5°±2.2, 4.6°±1.3 and 6.0°±0.9 respectively. Both the LFM and CMC showed, in general, moderate to good reliability except for pelvis tilt and hip rotation. CONCLUSION: Data demonstrated acceptable error margins especially for the sagittal and frontal plane. Low reliability for the pelvis tilt indicates that great effort is necessary to position the pelvic markers consistently during repeated sessions.
INTRODUCTION: Three-dimensional gait analysis (3DGA) in obese populations is a difficult task due to a great amount of subcutaneous fat. This makes it more challenging to identify anatomical landmarks, thus leading to inconsistent marker placement. Therefore, the purpose of this study was to investigate the test-retest reliability for kinematic measurements of obesechildren and adolescents. METHODS: Nine males and two females with an age-based BMI above the 97th percentile (age: 14.6±2.6years, BMI: 33.4±4.4kg/m2) were administered to two 3DGA sessions. To quantify reliability of discrete parameters the intraclass correlation coefficient (ICC2,k), standard error of measurement (SEM) and minimal detectable change (MDC) were calculated. To quantify waveform similarity, the coefficient of multiple correlation (CMC) and the linear fit method (LFM) were used. RESULTS: From 28 kinematic parameters, 23 showed acceptable ICCs (≥0.70) and the remaining parameters demonstrated moderate values. These were peak hip extension during stance (0.58), mean pelvis rotation (0.60), mean anterior pelvic tilt (0.64), peak knee flexion during swing (0.67) and peak hip abduction during swing (0.69). The SEM was below 5° for all parameters. The MDC for the sagittal, frontal, and transversal plane were on average 7.5°±2.2, 4.6°±1.3 and 6.0°±0.9 respectively. Both the LFM and CMC showed, in general, moderate to good reliability except for pelvis tilt and hip rotation. CONCLUSION: Data demonstrated acceptable error margins especially for the sagittal and frontal plane. Low reliability for the pelvis tilt indicates that great effort is necessary to position the pelvic markers consistently during repeated sessions.
Authors: Corinne A Jones; Ellen L Meisner; Courtney K Broadfoot; Sarah P Rosen; Christine R Samuelsen; Timothy M McCulloch Journal: Front Appl Math Stat Date: 2018-07-02