Orthopedic & Muscular System: Current Research
Open Access

Gait Scholarly Journal

Human gait refers to locomotion achieved through the movement of human limbs. Human gait is defined as bipedal, biphasic forward propulsion of center of gravity of the human body, in which there are alternate sinuous movements of different segments of the body with least expenditure of energy. Different gait patterns are characterized by differences in limb-movement patterns, overall velocity, forces, kinetic and potential energy cycles, and changes in the contact with the surface (ground, floor, etc.). Human gaits are the various ways in which a human can move, either naturally or as a result of specialized training.Gait also refers to a religious approach to life, one can walk with a narrow or wide gait.Human gaits are classified in various ways. Every gait can be generally categorized as either natural (one that humans use instinctively) or trained (a non-instinctive gait learned via training). Examples of the latter include hand walking and specialized gaits used in martial arts.Gaits can also be categorized according to whether the person remains in continuous contact with the ground.

The central nervous system regulates gait in a highly ordered fashion through a combination of voluntary and automatic processes. The basic locomotor pattern is an automatic process that results from rhythmic reciprocal bursts of flexor and extensor activity.This rhythmic firing is the result of Central Pattern Generators (CPG) which operate regardless of whether a motion is voluntary or not. CPGs do not require sensory input to be sustained.However, studies have identified that gait patterns in deafferented or immobilized animals are more simplistic than in neurologically intact animals. (Deafferentation and immobilization are experimental preparations of animals to study neural control. Deafferentation involves transecting the dorsal roots of the spinal cord that innervate the animal's limbs which impedes transmission of sensory information while keeping motor innervation of muscles intact.In contrast, immobilization involves injecting an acetylcholine inhibitor which impedes the transmission of motor signals while sensory input is unaffected.)

The complexity of gait arises from the need to adapt to expected and unexpected changes in the environment (e.g. changes in walking surface or obstacles).Visual, vestibular, proprioceptive, and tactile sensory information provides important feedback related to gait and permits the adjustment of a person's posture or foot placement depending on situational requirements. When approaching an obstacle, visual information about the size and location of the object is used to adapt the stepping pattern.These adjustments involve change in the trajectory of leg movement and the associated postural adjustments required to maintain their balance. Vestibular information provides information about position and movement of the head as the person moves through their environment. Proprioceptors in the joints and muscles provide information about joint position and changes in muscle length.Skin receptors, referred to as exteroceptors, provide additional tactile information about stimuli that a limb encounters.

Gait in humans is difficult to study due to ethical concerns. Therefore, the majority of what is known about gait in humans is ascertained from studies involving other animals or is demonstrated in humans using functional magnetic resonance imaging during the mental imagery of gait.These studies have provided the field with several important discoveries.