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Questions and Answers
The swing phase accounts for more than half of the gait cycle.
False
What percentage of one gait cycle is spent in the stance phase?
What is defined as the distance between consecutive initial contacts of the same foot with the ground?
Stride
_________ is the ability to assume an upright posture and maintain balance.
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Match the following gait cycle phases to their descriptions:
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Which muscular contraction is primarily active during the loading response phase of the gait cycle?
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Neurological control in gait involves sending sensory information to the muscles responsible for movement.
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The distance between initial contacts of the alternating feet is known as a __________.
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What is a defining characteristic of a scissors gait?
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A waddling gait typically indicates an injury to the peroneal nerve.
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What type of gait involves a stiff leg that either drags or swings around while walking?
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A ______ gait causes your ankles, knees, and hips to flex while walking.
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Match the gait types with their descriptions.
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Which gait is often associated with cerebellar degeneration?
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Complications from gait abnormalities can include increased risk of falls.
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What type of gait is characterized by a person experiencing a gradual inability to walk?
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What is the primary function of hip flexors during the swing phase of gait?
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The center of gravity (COG) remains static during the gait cycle.
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Explain what happens during the terminal swing phase.
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During mid-swing, the ankle ______ contracts to ensure foot clearance.
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Match the gait phase with its definition:
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Which of the following statements about gait abnormalities is true?
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Pelvic rotation during the swing phase helps to lengthen the limb.
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What role does early knee flexion play during gait?
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Study Notes
Gait
- Gait is the medical term for human locomotion, or the way we walk.
- Every individual has a unique gait pattern.
Normal Gait
- Normal gait is a series of rhythmical, alternating movements of the trunk and limbs that result in the forward progression of the center of gravity and the body.
- Four major criteria are essential to walking:
- Equilibrium: The ability to assume an upright posture and maintain balance.
- Locomotion: The ability to initiate and maintain rhythmic stepping.
- Musculoskeletal Integrity: Normal bone, joint, and muscle function.
- Neurological Control: Must receive and send messages telling the body how and when to move (visual, vestibular, auditory, sensori-motor input).
Gait Cycle
- One gait cycle is measured from heel-strike to heel-strike.
- It consists of two phases:
- Stance phase: The period of time that the foot is on the ground (~60% of one gait cycle). The leg accepts body weight and provides single-limb support.
- Swing phase: The period of time that the foot is off the ground moving forward (~40% of one gait cycle). The limb advances.
Stance Phase
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Initial Contact (Heel Strike): When the foot contacts the ground.
- Muscular contractions:
- Hip extensors contract to stabilize the hip.
- Quadriceps contract eccentrically.
- Tibialis anterior contracts eccentrically.
- Muscular contractions:
-
Loading Response (Initial Double Limb Support): Marks the beginning of the initial double limb stance, after initial contact until elevation of the opposite limb. Body weight is transferred onto the supporting limb.
- Muscular contractions:
- Ankle dorsiflexors (tibialis anterior) contract eccentrically to control plantar flexion moment.
- Quads contract to stabilize the knee and counteract the flexion moment (about the knee).
- Muscular contractions:
-
Mid-Stance (Single Limb Support): The initial period of single-leg support, from elevation of the opposite limb until both ankles are aligned in the coronal plane.
- Muscular contractions:
- Gluteus medius and calf muscles undergo eccentric contraction.
- Muscular contractions:
-
Terminal Stance (Single Limb Support): Begins when the supporting heel rises from the ground and continues until the opposite heel touches the ground.
- Muscular contractions:
- Toe flexors and tibialis posterior contract and are most active during this phase.
- Muscular contractions:
-
Pre-Swing (Second Double Limb Support): The start of the second double limb stance in the gait cycle. From initial contact of the opposite limb to just prior to elevation of the ipsilateral limb.
- Muscular contractions:
- Hip flexors contract to propel the advancing limb.
- Muscular contractions:
Swing Phase
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Initial Swing (Toe Off): The start of single limb support for the opposite limb, from elevation of the limb to the point of maximal knee flexion.
- Muscular contractions:
- Hip flexors concentrically contract to advance the swinging leg.
- Muscular contractions:
-
Mid-Swing (Foot Clearance): Following knee flexion to the point where the tibia is vertical.
- Muscular contractions:
- Ankle dorsiflexors contract to ensure foot clearance.
- Muscular contractions:
-
Terminal Swing (Tibia Vertical): From the point where the tibia is vertical to just prior to initial contact.
- Muscular contractions:
- Hamstring muscles decelerate the forward motion of the thigh.
- Muscular contractions:
Variables Affected During the Gait Cycle
- Pelvic Rotation: The pelvis rotates 4 degrees medially (anteriorly) on the swing side, lengthening the limb as it prepares to accept weight.
- Pelvic Tilt: The pelvis drops 4 degrees on the swing side, lowering the center of gravity at midstance.
- Knee Flexion in Stance: Early knee flexion (15 degrees) at heel strike lowers the center of gravity, decreasing energy expenditure. Also, absorbs the shock of heel strike.
- Foot Mechanisms: Ankle plantar flexion at heel strike and the first part of stance.
- Knee Mechanisms: At midstance, the knee extends as the ankle plantar flexes and the foot supinates, restoring the leg to its original length and reducing the fall of the pelvis at the opposite heel strike.
- Lateral Displacement of Pelvis: The pelvis shifts over the stance limb. The center of gravity must lie over the base of support (stance limb).
-
Center of Gravity (COG): In a standing position, it is 5 cm anterior to the S2 vertebral body.
- Vertical displacement: The center of gravity displaces vertically in a rhythmic pattern during the gait cycle. The highest point is during the midstance phase, and the lowest point occurs at the time of double limb support.
- Horizontal displacement: The center of gravity displaces 5 cm horizontally during an adult male step.
Abnormal Gait
- An abnormal gait is a change to your walking pattern.
- Anything that affects the brain, spinal cord, legs or feet can change your gait.
- Gait abnormalities are more common as you age.
Types of Gait Abnormalities
- Scissors Gait: The knees and thighs hit or cross in a scissors-like pattern when you walk. Steps may be slow and small. Common in people diagnosed with spastic cerebral palsy.
- Spastic Gait (Hemiplegic Gait): Walking with one stiff leg. When you lift that leg to walk, it either drags or swings around in a semicircular motion (circumduction). Common in people diagnosed with cerebral palsy, multiple sclerosis or hemiplegia.
- Waddling Gait: Exaggerated upper body movement, creating a waddling or duck-like walk. Progressive muscular dystrophy or hip dislocation present from birth can produce a waddling gait.
- Steppage Gait (Neuropathic Gait): High step, where you elevate your hip to lift your leg higher than normal. Your foot may appear floppy when it drops. Your toes usually point down and scrape the ground when you walk. Muscle atrophy or a peroneal nerve injury (like from spinal stenosis or a herniated disc), can cause a steppage gait.
- Crouching Gait: Ankles, knees and hips flex while you walk, often looking like you’re about to bend down. Your toes may drag. Common in people with cerebral palsy.
- Ataxic Gait: Irregular steps that affect your ability to walk in a straight line when you walk heel to toe. You may feel unsteady. Occurs with cerebellar degeneration.
- Shuffling Gait: Walking without lifting your feet completely off the ground, causing your feet to drag. You may shuffle if you feel off balance or have an injury that prevents you from lifting your feet off the ground when you walk.
- Lurching Gait: Common among people affected by paralysis or weakness of the gluteus area (the muscles near your hips and butt). It causes a slow and long stride. Your upper body can jerk forward or backward to lessen the weight on your affected leg.
Complications of Gait Abnormalities
- Increased risk of falls or injuries
- Muscle weakness
- Sudden inability to walk
- Pain
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Description
Explore the intricacies of human locomotion through this quiz on gait and normal gait patterns. Understand the essential criteria for walking, the phases of the gait cycle, and factors affecting gait. Test your knowledge on equilibrium, locomotion, and musculoskeletal integrity.
