RESUMEN
BACKGROUND: The gait variable minimum toe clearance (MTC) has been investigated concerning trip-related fall research in older adults. However, comparing studies is difficult due to the different methods used to measure MTC and shoe conditions, which may affect agreement. Measurement methods can include using a single virtual point (SVP), multiple virtual points (MVPS), or metatarsal head markers (marker-based). The shoe types used in MTC studies include standard shoes (SS), personal shoes (PS), and barefoot (BF) conditions. RESEARCH QUESTION: What is the agreement, inter and intra-rater reliability, and repeatability for the 3 commonly used methods of measuring MTC (SVP, MVPS, marker-based) under the 3 shoe conditions for optical motion capture systems (SS, PS, BF)? METHODS: Twelve healthy young adults (mean [SD] 23.8 [1.9] years,7 males) participated in this observational study. In a randomized order, participants completed 25 walking trials at self-selected normal and slow speeds in SS, PS, and BF conditions while infrared cameras recorded the maker trajectories. Each participant performed a familiarization trial for at least 1â¯minute before collecting data on each shoe condition. Statistical analyses included Bland-Altman 95â¯% limits of agreement (LOA) analyses, interclass correlation coefficient (ICC) analyses for inter- and intra-rater reliability, and the repeatability coefficient (RC). RESULTS: The SVP and MVPS had a tighter 95â¯% LOA than the marker-based method, particularly under SS and BF conditions. The inter-rater reliability was good to excellent under these shoe conditions. Intra-reliability for all methods under all shoe conditions was excellent (ICC >.90). The RC was very similar for each method, with none exceeding 1.02â¯cm. SIGNIFICANCE: The study provides estimates of the agreement between MTC methods and suggests that only SVP or MVPS produced similar results in SS/BF conditions. Additionally, a "true" change in MTC requires a difference greater than 1.02â¯cm.
Asunto(s)
Zapatos , Humanos , Masculino , Reproducibilidad de los Resultados , Femenino , Adulto Joven , Adulto , Dedos del Pie/fisiología , Variaciones Dependientes del Observador , Fenómenos Biomecánicos , Análisis de la Marcha/métodos , Marcha/fisiología , Captura de MovimientoRESUMEN
BACKGROUND: Approximately one-third of falls are caused by the swing foot contacting an object or the ground, resulting in a trip. The increased incidence of trip-related falls among older adults may be explained by greater within-person minimum toe clearance (MTC) variability. RESEARCH QUESTION: Will kinematic variability at any of the 6 major joints in the lower limbs, individually or in combination, be associated with MTC variability? METHODS: This cross-sectional study investigated whether single or multiple joint movements best explained MTC variability in older adults. Twenty healthy older adults (7 males, 13 females; mean ageâ¯=â¯71.3⯱â¯7.2 years) were recruited. Participants were fitted with a modified Cleveland Clinic marker set and walked for 50 trials at self-selected speeds over a 7-meter walkway (with a rest at 25 trials) while 6 infrared cameras recorded kinematics. RESULTS: Seven joint movements were evaluated, and swing hip flexion-extension variability was the only joint movement significantly associated with MTC variability (râ¯=â¯0.577, pâ¯=â¯0.008) and explained 29.6% (adjusted R2) of the variance of MTC variability in older adults (F (1, 18)â¯=â¯8.897, pâ¯=â¯0.008). SIGNIFICANCE: Identifying the joint movement/s associated with inconsistencies in toe clearance will improve our understanding of endpoint control in older adults and may lead to the development of effective trip prevention strategies.
Asunto(s)
Accidentes por Caídas/prevención & control , Marcha/fisiología , Dedos del Pie/fisiología , Caminata/fisiología , Anciano , Fenómenos Biomecánicos , Estudios Transversales , Femenino , Humanos , MasculinoRESUMEN
Although the visual (VIS) method for muscle activation onset detection has been the gold standard, this method has been criticized because of its moderate reproducibility and for being laborious. The simple threshold (STH), approximated generalized likelihood-step (AGL-step), and k-means (KM) algorithms are more repeatable and less laborious but require validation for gait speeds encountered in clinical research. We, therefore, assessed the intra-rater reliability of the VIS method and the concurrent validity of the algorithms against the VIS for 3 gait speeds. We recruited 10 healthy young adults (4 male, 6 female; mean age=28.5±4.2). Participants completed 10 walking trials each at 3 speeds. Electromyographic data from 1 gait cycle (GC) were collected from 6 right lower extremity muscles during each trial. We used custom Labview programs to determine muscle activity onset for all 4 methods. Repeatability coefficients for the VIS method ranged from 12.51% to 45.08% of the GC, depending on the muscle. The AGL-step algorithm agreed best with the VIS method (root mean squared error (RMSE) 0.86-6.95% of GC) followed by the STH (1.19-15.6% of GC) and KM (4.6-16.9% of GC) methods. A single rater demonstrated large errors (RMSE 8-23% of GC) between VIS assessments. Based on this study's parameters, the AGL-step agreed best with the VIS method and may be an alternative to the VIS.
Asunto(s)
Algoritmos , Electromiografía/métodos , Músculo Esquelético/fisiología , Adulto , Femenino , Marcha , Humanos , Masculino , CaminataRESUMEN
Regional plantar pressures during stair walking may be injurious in at risk populations. However, limited data are available examining the reliability of plantar pressure data collected during stair walking. The aims of this study were three fold; to assess the reliability of the plantar pressure data recorded during stair walking, to assess the effects of level ground and stair walking on plantar loading, and to develop regression equations to predict regional plantar pressures in stair walking from those collected on level ground. Fifteen subjects without conditions affecting their ability to walk on level surfaces or stairs were recruited. Each participant performed at least 10 steps in level ground and stair walking while plantar pressure data were recorded in six foot regions. Reliability was assessed using Intraclass Correlation Coefficient. A repeated measures ANOVA was used to assess the effect of activity on plantar pressure, and a linear regression was used to predict forefoot loading during stair walking. A reliability of 0.9 was achieved within 10 steps in all foot regions, with the forefoot requiring fewer steps. Plantar pressures were influenced by both, foot region and activity, with the heel and forefoot regions generally experiencing lower peak pressures and maximal forces during stair walking than level ground walking. The regression equations predicting peak pressure during stair walking accounted for between 37% and 70% of the variance of the stair walking data. These findings establish the reliability of plantar pressure data collected during stair walking. Future studies should investigate these parameters in clinical populations.