Normal and Pathological Gait in the Elderly Peggy R. Trueblood, PhD, PT California State University, Fresno

Part I EFFECTS OF NORMAL AGING ON THE GAIT PATTERN

Gait Cycle  Largest unit used to describe gait  Defined as foot contact to foot contact of same limb

Stride  Distance parameter between these two points  Within a stride we have right and left step

FLOOR CONTACT PATTERNS  SWING PHASE (40%)  STANCE PHASE (60%) - Initial Double Stance (10%) - Single Limb Support (40%) - Terminal Double Stance (10%)

Normal Gait is Dependent on:  Free passive joint mobility  Appropriate timing of muscles  Appropriate intensity of muscle action  Normal sensory input (proprioceptive, vestibular, visual)

Normal Aging  Can produce muscle weakness  Can affect visual, proprioceptive, and vestibular systems  Should not affect range of motion  Should not affect timing of muscle activity

Muscle Weakness  Hip extensors  Knee extensors  Plantarflexors  Dorsiflexors

Changes in Visual System  Decrease in visual acuity  Poorer depth perception  Restriction of the visual field  Increased susceptibility to glare

Changes in Somatosensory System  Increased sway with eyes closed  Decreased reflexes at the joints  Vibration and tactile sense decreases significantly after age 50, especially in the feet  Impaired proprioception on neurologic exam

Changes in Vestibular System  Slower postural support responses  Sway during standing increases with advancing age

What are the consequences?

COMMON GAIT ADAPTATIONS IN OLDER ADULTS

SENSORY/BALANCE DYSFUNCTION  Increase in double limb support  Decrease in gait velocity  Decrease in stride length  Increase in step width

MUSCLE WEAKNESS  Subtle changes in gait cycle due to muscle weakness

REVIEW PHASES OF GAIT CYCLE  Comparing Young and Old

WEIGHT ACCEPTANCE (Initial Contact & Loading)  Most demanding task in the gait cycle  Three functional patterns needed - Shock absorption - Initial limb stability - Preservation of progression

Key Muscle Groups  Hip extensors  Quadriceps  Dorsiflexors

SINGLE LIMB SUPPORT Midstance & Terminal Stance  One limb has the total responsibility for supporting body weight  Progression of body weight must be continued

Key Muscle Groups  Lateral hip stabilizers (abductors)  Trunk  Quadriceps  Plantarflexors

LIMB ADVANCEMENT (Pre-Swing & Swing)  Preparatory posturing begins in stance  Swing phase accomplishes: - limb advancement - toe clearance - forward reach

forward propulsion of the body preparation of limb for weight acceptance

Toe clears floor by 1 cm

Key Muscle Groups  Hip flexors  Knee flexors  Dorsiflexors  Quadriceps and Hamstrings at Terminal Swing

Normal Gait

Summary of Major Gait Adaptations in Elderly