making life livable: Gait Disorders in Elders

Gait Disorders in Elders

A slowing of gait speed or a deviation in smoothness, symmetry, or synchrony of body movement.

For the elderly gait speed, chair rise time, and the ability to perform tandem stance are independent predictors of their ability to perform instrumental activities of daily livingeg, the ability to shop, travel, and cook.

Gait speed, chair rise time, and balance are also predictors of the risk of medical care and death.

Walking without assistance requires the effective coordination of adequate sensation, musculoskeletal and motor control, and attention.

Normal age-related changes in gait

Gait velocity remains stable until about age 70; it then declines about 15% per decade for usual gait and 20% per decade for maximal gait.

Cadence

Step length is shorter in the elderly.

Double stanceincreases with ageto > 26% in healthy elderly persons.

Walking posture

i. osteoporosis with kyphosis

ii. increase in lumbar lordosis

iii. 5° greater "toe out”

Joint motion

i. Ankle plantar flexion is reduced during the toe off

ii. Maximal ankle dorsiflexion is not reduced

iii. The overall motion of the knee is unchanged.

iv. Hip motion is unchanged in the sagittal plane but in the frontal plane shows greater adduction.

v. Pelvic motion is reduced in the frontal and transverse planes, and transverse plane rotation is reduced.

Etiology and symptoms

In normal, the movement of the body is usually symmetrical. Step length, cadence, torso movement, and ankle, knee, hip, and pelvis motion are equal on the right and left sides.

· Loss of symmetry of motion and timing between left and right sides

i. Producing regular asymmetry with unilateral neurologic or musculoskeletal disorders.

ii. Symmetric short step length usually indicates a bilateral problem.

iii. Unpredictable or highly variable gait cadence, step lengths, and stride widths indicate breakdown of motor control of gait due to a cerebellar or frontal lobe syndrome.

· Pseudoclaudication symptoms

Pain, weakness, and numbness with walking that improves when sitting downmay be caused by spinal stenosis.

· Difficulties in initiation of gait

Represent isolated gait initiation failure, evidence of Parkinson’s disease, or evidence of frontal or subcortical disease.

· Gait initiation failure

Due to high-level sensorimotor disorder may progress to other abnormalities, including stiff posture with short steps, retropulsionin stance, weak or poor corrective responses to perturbations of balance when walking, and a highly variable and unstable gait pattern.

· Footdrop

· Spasticity or lowering of the pelvis due to muscle weakness of the proximal muscles on the stance side (particularly gluteus medius).

· Short step length

i. Psychogenic

ii. Neurological

iii. Musculoskeletal

· Irregular and unpredictable trunk instability can be caused by

i. Cerebellar, subcortical, and basal ganglia dysfunction.

ii. Knee arthritis (antalgic gait).

iii. Hemiparesis

· Deviations from path are strong indicators of motor control deficits. Wide stride width can be caused by cerebellar disease, if the width is consistent. Variable stride width suggests poor motor control, which may be due to frontal or subcortical gait disorders.

Diagnosis

Diagnosis is best approached in four parts:

History
Observe gait with and without an assistive device (if safe)
Assess all components of gait & observe gait again with a knowledge of the patient's gait components

A performance-oriented assessment tool may be helpful, as many other tests.

Clinical examination:

i. Measurement of stride length

ii. Measurement of gait kinetics

iii. Balance is impaired if the patient is unable to perform tandem stance or single leg stance for >= 5 seconds.

iv. Proximal muscle strength is tested by having the patient get out of a chair without using his arms.

v. Gait velocity is measured using a stopwatch. Gait velocity in healthy elderly persons ranges from 1.5 to 1.1 meters/second.

vi. Cadence is measured as steps/minute. Cadence varies with leg length.

vii. Step length, the easiest way to measure or calculate the patient's foot length; normal step length is three foot lengths. The following equation calculates average step length in centimeters: 10 × velocity × time to take 10 steps. An equivalent calculation is 0.16 × velocity × cadence (steps/minute).

viii. Step height

ix. Asymmetry or variability of gait rhythm

Prevention and treatment

i. High levels of physical activity help maintain mobility, even in patients with disease. A regular walking program of 30 minutes/day is the best single activity for maintaining mobility. The patient should be instructed to increase gait speed and duration over 4 months.

ii. Stretching

iii. Resistance training

iv. Balance exercises

v. Joint range of motion

vi. Develop muscle power and motor control.

vii. The positive psychological effects are difficult to measure but are probably just as important.

viii. Training of assistive devices use by therapists.

Evaluation of the elderly patient with an abnormal gait

Distinguishing between the normal gait of the elderly and pathologicgaits is often difficult.

Pathologic gaits with neurologic causesinclude:

i. frontal gait

ii. spastic hemiparetic gait

iii. parkinsoniangait

iv. Ataxic gait

Pathologicgaits with combined neurologic and musculoskeletal causes include^:

i. myelopathic gait

ii. stooped gait of lumbar spinal stenosis

iii. steppage gait

Pathologic gaits with musculoskeletal causesinclude:

i. antalgic gait

ii. coxalgic gait

iii. trendelenburg gait

iv. kneehyperextension gait

(Moe r. Lim et al Journal of the American Academy of Orthopedic Surgeon 2006.)

Infrared computerized stroboscopic photometry was used to measure the kinematic profile of walking of 20 young adults and 20 neurologically healthy elderly people. Compared with the young adults, the elderly exhibited 17–20% reductions in the velocity of gait and length of stride. The elderly also exhibited comparable reductions in the maximum toe-floor clearance, arm swing, and rotations of the hips and knees, but these alterations in gait were attributable to the reduction in stride length, which may have non-neurological causes.

(Journal of neurology, Springerlink3 September 1990)

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