Chapter 9: Gait, Prosthetics, and Orthotics

OVERVIEW

Normal human gait is a method of bipedal locomotion involving the complex synchronization of the neuromuscular and cardiovascular systems.¹

GAIT PARAMETERS

Walking involves the alternating action of the two lower extremities. The walking pattern is studied as a gait cycle (Figure 9–1). The gait cycle, which can be defined as the interval of time between any repetitive walking events, consists of two phases (Figure 9–1) and seven intervals (Figure 9–2). The major requirements for successful walking include the following²:

• Support of body mass by the lower extremities.

• Production of a locomotor rhythm—the stretch reflex and the extensor thrust.³ The stretch reflex is involved in the extremes of joint motion, while the extensor thrust may facilitate the extensor muscles of the lower extremity during weight-bearing.⁴

• Dynamic balance control of the moving body.

• Propulsion of the body in the intended direction.

• Adaptability of locomotor responses to changing tasks and environmental demands.

During the gait cycle:

• The swing of the arms is out of phase with the legs. Unless restrained, the arms tend to swing in opposition to the legs, the left ...