preview

Leg Disturbance: A Semantic Analysis

Decent Essays
Clinically, one leg stance is frequently used to assess postural stability or balance (Tinetti 1986, Berg, Wood-Dauphine et al. 1989, Hurvitz, Richardson et al. 2001, Horak, Wrisley et al. 2009). Initiating one leg standing involves a moving the center of mass over the stance leg that requires the control of weight support, vertical alignment of the body, and balance/equilibrium (Jonsson, Seiger et al. 2004). A high center of gravity and a small base of support complicate the problem of maintenance of balance (Winter 1995). Normally, postural control is the act of maintaining, achieving or restoring the state of balance during any posture or activity. It is described by the relationships between stability, base of support the line of gravity…show more content…
Stability refers to the inherent ability of a body to remain in or return to a specific state of balance and not to fall (Pollock, Durward et al. 2000). Optimal postural control requires intact sensory motor functioning. Treating the body’s balance is detected by sensory (afferent) system, and responses through motor (efferent) system. The sensory system has information on COM motion relative to the direction of gravity for vestibular cues, visual orientation for visual cues, and support surface orientation for proprioceptive cues (Peterka 2002). While the motor system counteracts the force of gravity for preventing falling via muscle activity represented as postural control strategies. In quiet standing, the persons never truly stand still, although they try stand still. These unavoidable vertical posture changes or postural sway must be occurred as an inverted pendulum model. The body represents the fixed-support strategy e.g. the ankle and hip strategies during controlling balance, and acts the change-in-support strategy e.g. stepping or grasping strategies during loosing balance (Horak and Nashner 1986, Pollock, Durward et al.
Get Access