Gait Flashcards
Average Stride Length
28-32 inches
Stride = same foot to same foot
Average Cadence
90-120 steps/minute
Women higher by 6-9 steps/minute
Average Speed
3 mph
Gait Cycle
From heel strike to next heel strike of same foot
Phases:
Stance - when foot is in contact with ground
Swing - when foot is not in contact with ground
Gait Cycle Phases
Heel-strike to foot-flat (contact)
Foot-flat to heel-off (mid-stance)
Heel-off to toe-off (propulsion)
Toe-off to heel-strike (swing)
Contact Phase
Lateral calcareous strikes ground
At point of impact, tibia internally rotates
Calcareous everts and talus drops and addicts to unlock midtarsal joints - provides maximum shock absorption
Foot lowered eccentrically to ground by extensor digitorum longus and tibialis anterior muscles
Mid-stance Phase
Flat-food to heel-off
Rearfoot fully pronates
Metatarsals hit ground to bring foot flat on ground
Body’s center of gravity passes from behind to over foot
Subtalas joint resupinates (calcareous everts and talus abducts)
Locks midtarsal joints
Transforms foot from shock absorber to a rigid lever
Posterior tibialis m. = important restraint to overpronation; active foot supinator
As body passes over mid-foot it places ankle in maximal dorsiflexion, putting a maximal preload on the gastrocnemius-soleus complex
Propulsion Phase
Heel-lift to toe-off
As heel rises body continues forward over metatarsals and begins to pull heel off ground
Extension of metatarsalphalangeal (MTP) joint - especially 1st MTP => windlass effect of plantar fascia that elevates the arch and further assists in supination of foot
Foot = rigid lever and used to propel body forward by maximal contraction of gastrocnemius-soleus and hamstrings
Toe-off: line of progression passes between 1st and 2nd metatarsals that are in maximal extension
Phase concludes with body weight moving over great toe at toe-off
Swing Phase
Last phase
Foot dorsiflexes to keep toes from hitting ground
Supinates to position foot for lateral calcareous to make contact at heel strike
Cycle repeats
Stance
From heel strike (initial contact) to toe off (pre swing)
60% of gait cycle
When foot is on ground and weight bearing
Most problems occur during stance phase
Swing
From toe off to heel strike
40% of gait cycle
Foot moves forward and is not weight bearing
Function of the 8 Phases of Gait
- Initial contact
* establish contact with leading foot, begin STANCE - Loading response
* shock absorption
* begin weight bearing
* continue progression of forward movement - Mid stance
* limb & trunk stability
* progression over stationary foot - Terminal stance
* progression past stationary foot
* prepare for swing - Pre swing
* weight release from stationary foot
Position limb for swing - Initial swing
* prepare for foot clearance
Advance food from trailing position - Mid swing
* foot clearance
* limb advancement - Terminal swing
* prepare for stance
* complete limb advancement
Requirements of Gait
Stability in stance Foot clearance in swing Pre-position for initial contact Adequate step length Energy conservation
Stability in Stance
Single limb support for a total of 80% of gait cycle (40% for each foot)
Stable foot, ankle, knee, hip, torso
Foot Clearance in Swing
Requires coordination of entire limb
- ankle dorsiflexion
- knee flexion
- hip flexion
- retain stability in stance
Pre-position for Initial Contact
Foot-ankle-knee-hip all in correct alignment
Ready to place foot in desired location
Ready to absorb weight transfer
Adequate Step Length
Too short: expend energy, minimal progress
Too long: lose balance, strain ligaments and muscles
Conservation of Energy
Center of gravity moves more than 2 inches up and down during gait cycle
Accomplished through pelvic list (in early stance, as weight is transferred to foot, hip on non-weight bearing side DROPS about 2 inches)
Considered energy efficient (otherwise would have to raise, expend more energy to lift entire leg mass)
Innominate (Pelvic) Rotation
As foot moves forward for heel strike, innominate rotate forward (anteriorly) in a sagittal plane
“Lengthens” femur (some compensation for pelvic list)
Rotation about 4 degrees, reverse in stance phase
Lateral Displacement of Pelvis
2 legged walk, feet hit about 2-4 inches apart
Only 1 foot on ground 80% of time (total booth feet in cycle)
Center of mass has to compensate
Pelvis shifts laterally about 2 inches
Facilitates abduction of hit during stance
Antalgic Gait
Adopted limp to avoid pain on weight-bearing structures
Characterized by a very short stance phase on affected side
Common Causes: Trauma Osteoarthritis Pelvic girdle pain Coxalgia Tarsal tunnel syndrome
Arthrogenic Gait
Due to stiffness in affected joints (usually hip or knee) from deformity/decreased joint space
Plantar flexion of foot opposite to affected side to increase clearance
Affected leg is circumducted (passive circular motion)
Step is usually shorter
Not always painful
Common Causes:
Osteoarthritis of hip or knee joints
Post orthopedic surgeries of hip or knee
Ataxic Gait
Unsteady, uncoordinated walk Needs broad base of support: wide base and feet thrown out Loss of sensation or control May lurch or stagger Patient often watches feet when walking
Common Causes Vestibular Cerebellum abscess/hemorrhage Friedreich's ataxia Pontine-cerebellar atrophy Chronic mercury poisoning Posterior fossa tumor Wernicke's syndrome (chronic alcohol abuse) Drugs
Parkinsonian (Festinating) Gait
Characterized by small shuffling steps
Hypokinesia (general slowness of movement)
In extreme cases - akinesia (total loss of movement)
Reduced stride length and walking speed while cadence rate is increased
Exhibited by some patients with Parkinson’s Disease (PD)
Steppage (Foot Drop, High Stepping, Neuropathic) Gait
Full foot drop
Hip raised very high to clear toe
Usually a quiet gait
Common Causes: Peroneal (common fibular) nerve injury as a result of: * lumbar disc herniation (most common) * poliomyelitis * multiple sclerosis * Guilain-Barre syndrome * Parkinson's disease
Hemiplegic Gait
Leg is stiff, without flexion at knee and ankle, and with each step is rotated away from the body, then towards it, forming a semicircle
Average Step Length
14-16 inches
