title: Intra-individual gait pattern variability in specific situations: Implications for forensic gait analysis.
abstract: In this study, inter- and intra-individual gait pattern differences are examined in various gait situations by means of phase diagrams of the extremity angles (cyclograms). 8 test subjects walked along a walking distance of 6m under different conditions three times each: barefoot, wearing sneakers, wearing combat boots, after muscular fatigue, and wearing a full-face motorcycle helmet restricting vision. The joint angles of foot, knee, and hip were recorded in the sagittal plane. The coupling of movements was represented by time-adjusted cyclograms, and the inter- and intra-individual differences were captured by calculating the similarity between different gait patterns. Gait pattern variability was often greater between the defined test situations than between the individual test subjects. The results have been interpreted considering neurophysiological regulation mechanisms. Footwear, masking, and fatigue were interpreted as disturbance parameters, each being a cause for gait pattern variability and complicating the inference of identity of persons in video recordings.
authors.affiliation: Saarland University, Institute for Sport Science, Geb. B 8.1, 66041 Saarbruecken, Germany. Electronic address: oliver.ludwig1@uni-saarland.de.
authors.forename: Oliver
authors.initials: O
authors.lastname: Ludwig
authors.affiliation: Federal Criminal Police Office (BKA), Forensic Science Institute, KT 33, Aeppelallee 45, 65173 Wiesbaden, Germany.
authors.forename: Steffen
authors.initials: S
authors.lastname: Dillinger
authors.affiliation: Saarland University, Institute for Sport Science, Geb. B 8.1, 66041 Saarbruecken, Germany.
authors.forename: Franz
authors.initials: F
authors.lastname: Marschall
mesh_terms: D001696:Biomechanical Phenomena / Q000502:physiology; D056667:Biometric Identification / Q000379:methods*; D005260:Female; D044707:Forensic Sciences / Q000379:methods; D005684:Gait / Q000502:physiology*; D006260:Head Protective Devices; D006801:Humans; D007596:Joints / Q000502:physiology; D035002:Lower Extremity / Q000502:physiology; D008297:Male; D018763:Muscle Fatigue / Q000502:physiology; D012775:Shoes; D014741:Video Recording; D016138:Walking / Q000502:physiology
keywords: CCTV; Forensic science; Gait analysis; Gait biometrics; Identification; Variability