Course:KIN366/ConceptLibrary/Gait

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Movement Experience for Children
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KIN 366
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Instructor: Dr. Shannon Bredin S.D Bredin
Email: shannon.bredin@ubc.ca
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Gait in humans can be characterized by a set of coordinated motor movements, resulting in bipedal locomotion. Execution involves a complex series of working parts including musculoskeletal support, joints, and neural connections (Keen, 1993). A normal gait sequence can be broken down into two main phases; a stance phase and a swing phase. These phases are cyclic and together result in forward propulsion of ones’ centre of gravity (Miller, 2007). Infants typically begin to develop regular gait patterns between the ages of 0 and 4.The development process can be hindered by a number of factors including; neural development, structural and disease (Sutherland 1984). Gait disturbances among infants are common and tend to correct themselves though observation and practice. (Klenerman & Wood, 2006) In extreme cases uncorrected gait abnormalities can lead to pathological gait and therefore disturbances in a child’s lifelong movement experiences.

Gait Cycle Components

Gait Cycle.png

The gait cycle, otherwise known as the walking cycle involves 2 phases; the stance phase and the swing phase. The stance phase accounts for 60-62% of the full cycle and the remaining 40-38% is comprised of the swing phase. (Ayyappa, 1997)

Stance Phase

The stance phase provides the body support on the ground and can be broken down into four components; heel strike, foot flat, mid-stance and toe-off (Miller, 2007). To begin, the heel of one foot makes initial contact with the ground (heel strike). Next, the foot spreads out fully, distributing body weight on to the outstretched leg (foot flat) and is sometimes called “the loading phase” (Miller, 2007) Midstance marks the point at which the tibia is perpendicular to the ground and Toe off is the moment when the toe finally prepares to lift off the ground. (Miller, 2007)

Swing Phase

During the swing phase the foot is off the ground. Initial swing begins at toe off and continues until maximum knee flexion occurs. Mid-swing extends, as the leg swings forward until the tibia is perpendicular to the ground. Terminal Swing marks the end of the swing phase, where the tibia is vertical and the beginning of a new cycle. (Miller, 2007)

Double Support

Double support is both the “initial and terminal double-limb stance” (Ayyappa, 1997). The terms describe when both feet are in contact with the ground at the same time. Double support accounts for 25% of the gait cycle (Ayyappa, 1997)

Single Support

Single support is when only one leg is in contact with the ground and can be seen throughout the swing phase. Whilst one foot is in the air, the other provides single support. (Ayyappa, 1997)

Fundamental Gait Terminology

Numerous factors can be considered when assessing the efficiency and functionality of an individuals’ gait. Some of which include width of walking base, step length, cadence, duration of a single limb in stance and walking velocity. From a developmental perspective, determining specific terminology can aid in distinguishing gait variations as a child matures.

Stance Width

Stance width is the side-to-side distance between two feet along a horizontal plane. The wider the base of support, the easier it is to maintain control over ones balance center of mass and therefore, ones balance (Burtner & Woollacott, 1999) As a child grows, the width of their walking base becomes narrower and narrower. (Sutherland, 1984) Theories explain that over time, children gain confidence through the progressive myelination process (Keen, 1993) and require less of a base of support.

Step length

Step length is the longitudinal distance between the two feet. This parameter is related to change in height and leg length of a child. (Buckland, 2014) Step length steadily increases throughout adolescence until growth is complete. (Woollacott,1989)

Cadence

Cadence refers to the frequency of steps taken in a given amount of time (steps/min) (Woollacott, 1989). (Sutherland, 1997) report a dramatic decrease in cadence between 2.5-3 years. Explanations suggest that this is highly related to growth. (Sutherland,1997)

Duration of Single-Limb Stance

Single-limb stance duration is the duration of time that one foot is on the ground during stance phase. If this variable increases, it implies an increase in stability. In other words, one can balance on one foot for longer periods of time. By 3.4-4 years, single-limb stance ability closely resembles that of an adult. (Sutherland,1997)

Walking Velocity

Velocity of gait is the rate of walking and can be expressed as the product of step length and cadence (Sutherland,1997). Velocity generally increases with age.

Typical Maturation of Gait

From childhood to adulthood, a fully developed gait pattern takes years to evolve. As we grow, certain motor milestones must be met in order to develop appropriately. Physiological processes including; growing and maturing body parts, posture, neurological development and range of motion about limbs and joints are the main causes of gait variation throughout the years (Keen,1993). (Sutherland,1984) examines gait patterns in a population of children and the following information highlights differences in gait as children mature.

Prenatal Movements

Before even being born, humans express a certain level of postural control in preparation to walk. As a fetus, stepping reflex movements closely resemble lower limbs movements during the independent walking. (Thelen & Cook, 1987)

Infant

"An infant can sit up by 6 months of age, crawl after 9 months, walk with support at 11 months and walk with immature posture by 12 months." (Sunderland, 1984) These movements all act as prerequisites to independent walking.

12 months

A child achieves independent walking at around 12 months of age and if not achieved by 16 months, gait is considered to be delayed. Infants walk with a wide base (step width) for increased balance, with their arms abducted in high guard position for protection from falls (Sutherland, 1984). Structurally, hips are externally rotated and feet are flat in appearance, causing short swing phases. Additionally, they display arched backs and increased knee and hip flexion. (Sutherland, 1984) Cadence is high but overall walking velocity is slow. Step length is short because at this age limb lengths are undeveloped. There is an absence of reciprocal swinging of the upper extremities with each footstep.

2 years

By 2 years the infant demonstrates a pronounced heel-strike at the point of contact with the ground. Pelvic tilt and external rotation is reduced almost completely and the overall gait cycle becomes smoother. (Sutherland, 1984) Reciprocal arm swing is incorporated to compliment leg swing. Step length and walking velocity also increases.

3 years

A 3 year olds’ gait pattern closely resembles that of an adult. By this time the child has developed a vigorous gait cycle with “reciprocal arm swing, well-developed heel strike and smooth movement between phases.” (Sutherland,1984) The child is now comfortable with a narrow base of support and hips are more internally rotated. Stride length, high cadence, low walking velocity and duration of single limb support is still below adult standards. (Sutherland 1984)

7 years

At age 7, increased limb length and stride length finally allows for reduced cadence. Despite this, overall walking velocity increases. (Sutherland,1984) A 7 year olds' gait pattern only differs slightly from a 3 year old pattern and differences can be attributed to growth of limbs.

Common Gait Abnormalities

Due to the complexity of human gait, abnormalities are difficult to determine. Knowledge of a typical gait pattern at various stages of life is crucial in the understanding of pathological gait. (Miller, 2007)

Intoeing

Intoeing is the most common gait disorder that parents are concerned about. When a child walks, the feet curve inwards instead of pointing straight forward (Keen, 2013). The problem lies in the feet, shins or thighs and these causes are named Tibial torsion, Femoral anteversion and Metatarsus Varsus (abnormal foot anatomy).

Metatarsus Adductus is a birth deformation where anatomically, the childs’ feet bend inwards. Merely stretching can overcome the deformity (Sutherland, 1984) Most common in preschool children, tibial torsion is internal rotation of the shin. This condition is regular for a child under 18 months, however measures should be taken if the problem persists past this age. (Sutherland, 1984) recommends the use of a splint to increase internal tibial torsion. Femoral anteversion depicts a walk with ones’ thighs internally rotated. In this case, parents are advised not to treat their children as they will naturally out-grow it. By age 2, any symptoms of intoeing should diminish and children walk with their feet pointing in the direction they are heading. (Keen, 2013)

Outtoeing

Outtoeing is a characteristic of excessive external rotation at the hip during gait (Keen, 2013) This rotational variation is seen in normal children but becomes a disorder when it persists into adulthood.

Significance of Gait

Gait is a fundamental motor skill required by humans to enable movement from one place to another. It is a compulsory milestone to reach in order to move onto more complicated skills such as running, hopping, jumping and skipping (Miller, 2007).

Recommendations for Parents

Parents are encouraged to refer to normal gait pattern information that is specific to their child’s age group. It is natural for a parent to be concerned about their child’s development but the majority of the time, perceived deformities are just part of the normal maturation process. If Intoeing, out toeing, foot flat or toe-walking continue into adulthood, a parent should consult a pediatric professional.

There is a misconception that special corrective shoes can enhance gait maturation however, (Staheli & Giffin, 1979) report that “special shoes are not necessary to promote normal foot development”.


References

Ayyappa, E. (1997). Normal Human Locomotion, Part 1: Basic Concepts and Terminology. American Academy of Orthotics and Prosthetists 9, 10-12. Retrieved from http://www.oandp.org/jpo/library/1997_01_010.asp

Buckland, M. A. (2014). The Effect of Torsional Shoe Flexibility on Gait and Stability in Children Learning to Walk. Pediatric Physical Therapy 26, 411-417. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/25251796

Burtner. A. B., & Woollacott M. H. (1999). Stance Balance Control with Orthoses in a Group of Children with Spastic Cerebral Palsy. Developmental Medicine & Child Neurology, 748-757. Retrieved from http://journals.cambridge.org/abstract_S0012162299001516

Keen, M. (1993). Early Development an Attainment of Normal Mature Gait. American Academy of Orthotists and Prosthetists. 5, 35-38. Retrieved from http://www.oandp.org/jpo/library/1993_02_035.asp

Klenerman, L., & Wood, B. (2006). The Development of Gait. The Human Foot, 4, 103-115. United States of America: Springer- Verlag London Limited.

Miller, F. (2007). Gait. Physical Therapy of Cerebral Palsy Springer New York 6, 207-342. Retrieved from http://link.springer.com/chapter/10.1007%2F978-0-387-38305-7_6

Sutherland, D. (1997). The Development of Mature gait. Elsevier Science, 6, 163-170. Retrieved from http://www.sciencedirect.com/science/article/pii/S0966636297000295

Sutherland, D. H. (1984). Gait Disorders in Childhood and Adolescence. B. Tansill (Eds.). California, CA: San Diego

Woollacott, S. C. (1989). Development of Posture and Gait Across the Life Span. G. H. Williams (Ed.). University of South Carolina

Thelen, E. & Cooke, D. W. (1987) Relationship between newborn stepping and later walking: a new interpretation. Dev Med Child Neurol. 3, 380-93.

Staheli, T. L, & Giffin, L. (1979). Corrective Shoes for Children: A Survey of Current Practice. Retrieved from http://pediatrics.aappublications.org/content/65/1/13