Background and ObjectiveAbsolute angle represents the inclination of a body segment relative to a fixed reference in space. This work compares the absolute and relative angles for exploring biomechanical gait constraints.MethodsGait patterns of different neuromotor conditions were analyzed using 3D gait analysis: normal gait, Cerebral Palsy, Charcot Marie Tooth and Duchenne Muscular Dystrophy, representing central and peripheral nervous system and muscular disorders, respectively. Forty-two children underwent gait analysis: 10 children affected by CP, 10 children by CMT, 10 children by DMD (...) and 12 healthy children. The kinematic and kinetic parameters were collected to describe the biomechanical pattern of participants’ lower limbs. The absolute angles of thigh, leg and foot were calculated using the trigonometric relationship of the tangent. For each absolute series, the mean, range, maximum, minimum and initial contact were calculated. Kinematic and kinetic gait data were studied, and the results were compared with the literature.ResultsStatistical analysis of the absolute angles showed how, at the local level, the single segments behave differently depending on the pathology. However, if the lower limb is studied globally, a biomechanical constraint emerges.ConclusionEach segment compensates separately for the disease deficit so as to maintain a global biomechanical invariance. Using a model of inter-joint co-variation could improve the interpretation of the clinical gait pattern. (shrink)

BackgroundGait Analysis of healthy people, imitating pathological conditions while walking, has increased our understanding of biomechanical factors. The influence of the pelvis as a biomechanical constraint during gait is not specifically studied. How could mimicking a pelvic attitude influence the dynamic mechanical interaction of the body segments? We proposed an investigation of the pelvic attitude role on the gait pattern of typically developed people when they mimicked pelvic anteversion and posteroversion.Materials and methodsSeventeen healthy volunteers were enrolled in this study. They (...) simulated a pelvic anteversion and posteroversion during walking, exaggerating these postures as much as possible. 3D gait analysis was conducted using an optoelectronic system with eight cameras and two force plates. The kinematic, kinetic, and spatio-temporal parameters were compared between the three walking conditions.ResultsIn Pelvic Anteversion gait we found: increased hip flexion, increased knee flexion during stance, and reduction of ankle flexion-extension Range of Motion compared with Pelvic Normal gait. In Pelvic Posteroversion gait compared with PN, we found: decreased hip flexion-extension RoM with a tendency to hip extension, decreased knee maximum extension in stance, and increased ankle maximum dorsiflexion in stance.ConclusionThe configuration of PA contains gait similarities and differences when compared with pathologic gait where there is an anteversion as seen in children with Cerebral Palsy or Duchenne Muscular Dystrophy. Similarly, attitudes of PP have been described in patients with Charcot-Marie-Tooth Syndrome or patients who have undergone Pelvic Osteotomy. Understanding the dynamic biomechanical constraints is essential to the assessment of pathological behavior. The central nervous system adapts motor behavior in interaction with body constraints and available resources. (shrink)