Gait Cycle

Conventions for naming components regarding the gait cycle This course employs the widely used terminology developed at the pathokinesiology science department of Rancho Los Amigos Hospital. Periods within stance phase Periods within swing phase References Moving images regarding the gait cycle The gait cycle begins when one foot contacts the ground and ends when that foot contacts the ground again. Thus, each cycle begins at initial contact with a stance phase and proceeds through a swing phase until the cycle ends with the limb's next initial contact. Stance phase accounts for approximately 60 percent, and swing phase for approximately 40 percent, of a lone gait cycle. Each gait cycle includes 3 periods when most feet are on the ground.

First period of double limb help begins at initial contact, and lasts for first 10 to 12 percent regarding the cycle. The 2nd period of double limb help occurs within the final 10 to 12 percent of stance phase. As the stance limb prepares to leave the ground, the opposite limb contacts the ground and accepts the body's weight. The 3 periods of double limb help account for 20 to 24 percent regarding the gait cycle's total duration. Stance phase of gait is divided into 4 periods: loading response, midstance, terminal stance, and preswing.

Swing phase is divided into 3 periods: initial swing, midswing, and terminal swing. The beginning and and ending of each period are defined by specific events. STANCE PHASE: Loading response begins with initial contact, the instant the foot contacts the ground. Normally, the heel contacts the ground first. In patients who demonstrate pathological gait patterns, the entire foot or the toes contact the ground initially.

Loading response ends with contralateral toe off, when the opposite extremity leaves the ground. Thus, loading response corresponds to gait cycle's first period of double limb support. Midstance begins with contralateral toe off and ends when the center of gravity is directly over the reference foot. Note that this phase, and early terminal stance, the phase discussed next, are the only times within the gait cycle when the body's center of gravity truly lies over the base of support. Terminal stance begins when the center of gravity is over the supporting foot and ends when the contralateral foot contacts the ground.

During terminal stance, around 35 percent regarding the gait cycle, the heel rises from the ground. Preswing begins at contralateral initial contact and ends at toe off, at around 60 percent regarding the gait cycle. Thus, preswing corresponds to gait cycle's 2nd period of double limb support. SWING PHASE Initial swing begins at toe off and continues until maximum knee flexion 60 degrees occurs. Midswing is the period from maximum knee flexion until the tibia is vertical or perpendicular to ground.

Terminal swing begins where the tibia is vertical and ends at initial contact. The gait cycle is divided into 3 phases: two Stance -- defined as the interval in which the foot is on the ground 60% regarding the gait cycle 3 Swing -- defined as the interval in which the foot is not in contact with the ground 40% regarding the gait cycle During evaluation regarding the gait cycle, a physical therapist distant assesses each portion of these 3 phases. Stance is divided into 4 phases:1 Heel strike to foot flat2 Foot flat through midstance3 Midstance through Heel off4 Heel off to Toe off Swing is divided into 3 phases:1 Acceleration to midswing2 Midswing to deceleration By evaluating each lone phase regarding the gait cycle, a physical therapist obtains clues into specific muscular weaknesses and shortening. Addressing these issues in a rehabilitation program shall lead to a more efficient gait pattern, resulting in decreased risk of injury, fewer life expenditure, greater functional independence, and improved muscular balance.