Reference Values And Characteristics Of Gait Using Inertial Sensor System

Background: Normal gait data reported showed variability depending on specific equipments and techniques.With respect to the gait of lower limes,reference values of Initial Contact Angle(ICA)and Toe-Off Angle(TOA)are still lacking.Objective: In the first part of this study,we presented normative gait database in 292 healthy adults using APDM Movement Monitoring inertial sensor system across a large age span of adulthood.Methods: Data were collected as participants completed a walk test for 2 minutes.Normalization was conducted and two factors were extracted by a factor analysis.Six reference gait variables under two factors were presented and the impacts of age,gender and BMI were evaluated by MANOVA and ANCOVA.Results: ICA and TOA were highly correlated with gait speed and stride length.ICA was significantly larger in men,whereas larger TOAs were observed in women in all age groups but could not achieve significant difference.Overweight and obese adults walked at significantly lower speed,shorter stride length,reduced cadence and longer gait cycle duration.TOA was smaller in the obese group.However,the differences in ICA were not significant.Background: Torso motions and arm swing are altered in some pathologies,especially meaningful in older adults.A comprehensive reference database of three-dimensional thoracic and pelvic kinematics of older adults during overground walking has not been established.The reference value for the arm swing maximum velocity is still lacking.Moreover,the relationships between these variables are not fully understood.Objective:Therefore,in the second part of this study,we presented reference values for three-dimensional thoracic and pelvic range of motion and arm swing maximum velocity in 113 healthy old adults in a 2-min walk test using APDM Movement Monitoring inertial sensor system.Methods: The effects of age and gender were assessed by two-way ANOVA,and post hoc Bonferroni correction was applied for multiple comparisons.The relationships between variables were investigated via multiple linear regression models.Results: In general,thoracic and pelvic plane motions showed reduced amplitude with aging.Gait speed,pelvis coronal plane motion and arm swing maximum velocity significantly declined with age.Only the pelvic sagittal plane motion showed a gender main effect.Coronal plane motions of the thorax and pelvis were closely associated,as were sagittal plane motions.Thoracic coronal plane motion was a significant predictor for pelvic transverse plane motion and vice versa.Thoracic transverse plane motion increased with thoracic sagittal plane motion.Gait speed,pelvic coronal and transverse plane motions and thorax sagittal plane motion were significant independent variables that influenced dominant arm maximum velocity.A larger maximum velocity was seen in the left arm.Conclusion: Reference gait values described herein were valuable for identification and interpretation of gait phenomena using APDM? and for future comparison with gait dysfunction to detect subtle changes in abnormal gait patterns,develop rehabilitation treatments and evaluate the outcomes of interventions.And these will contribute to the rehabilitation of gait dysfunction.