Abnormal gait or a walking abnormality is when a person is unable to walk in the usual way.
Abnormal gait may be due to injuries, underlying conditions, or problems with the legs and feet.
Walking requires many systems of the body, such as strength, coordination, and sensation, to work together.
The gait cycle begins when one heel strikes the ground supported by the stance of the leg, and then the body weight shifts to the opposite leg which flexes at the hip and knees and swings forward, eventually striking the heel on the ground: weight then shifts forwards on the opposite leg, while the other leg swings forwards, and again strikes the ground.
When one leg is in a stance phase, the opposite leg is in swing phase.
When both legs support the body weight, that is, double support, occurs when both legs make contact with the ground, it comprises 10% of the gait cycle.
Double support increases in abnormal gaits to compensate for unsteadiness.
A normal gait requires control of limb movements, muscle tone, and is an extraordinarily complex process involving the entire nervous systems.
Groups of neurons in the spinal cord and brain stem generate rhythmic activities and provide output to motor neurons, which subsequently activate muscles in the limbs.
The cerebral cortex integrates visual, vestibular, and proprioceptive system input, and also receives input from the brainstem, basal ganglia, cerebellum, and afferent neurons that carry proprioceptive signals from muscle stretch receptors.
The integration of all the above systems allow patients to walk straight, unencumbered and with the ability to avoid obstacles and then to adjust their gait to maintain their balance.
When one or more of these interacting systems is dysfunctional, it can result in abnormal gait or walking abnormality.
CNS lesions cause disturbances of gait and balance that frequently include excessively variable step length.
Peripheral nerve lesions in the limbs, such as an entrapment neuropathy, may cause abnormal abnormalities that repeat, machine like from one gate cycle to the next.
The gait examination begins with observation of the patient ideally in along hallway, with enough distance to observe walking speed with arm swings.
The gait is observed for its velocity, stride length, step length, and strep width or base.
The stride length measures the distance covered by a gait cycle.
The step measures the distance covered during the swing phase of a single leg.
The step width measures the distance between the left and right feet while walking.
Observation of the gait includes: posture, arm swing, height of steps, leg stiffness, side to side lurching, leg tone, muscle strength.
Examination of lower extremity reflexes and sensation are necessary factors, as well, to establish an etiology of a gait disorder.
Part of the gait exam is the Romberg sign performed with the patient standing feet together and eyes closed: a positive test is if it provokes a fall.
Heel to toe steps, the tandem test, can unmask subtle distal weakness.
Abnormal gait is prevalent in the elderly and affects approximately 1-3 community dwelling patients older than 60 years.
Gait disorders may be associated with diminished quality-of-life and increased nursing home placement and may be an indicator of progression to dementia in patient’s with mild cognitive impairment.
The gate cycle is initiated when one heel strikes the ground.
Gait disorders may be neurologic or non-neurologic in origin.
Gait disturbances may be due to:
illness
genetic factors
injury
abnormalities in the legs or feet.
Abnormal gait is categorized as one of five types.
spastic gait
scissors gait
steppage gait
waddling gait
propulsive gait
Non neurological causes of abnormal gait include: arthritis of the hip and knee, orthopedic deformities, visual loss, pain that reduces the stance of the affected limb, all resulting in an asymmetric antalgic gait.
With aging there is a mildly shortened step length, decreased velocity, widened base, and increased double support time.
With aging there is an increased perceived instability, either intrinsic or extrinsic.
Cautious gait refers to patients walking with their hands outstretched in an attempt to steadt themselves, and it may herald an underlying neurological gait disorder.
Spastic gait occurs when a person drags their feet while walking, appearing stiff.
Spastic gaits are caused by lesions in the corticospinal tract any level, and may be the unilateral or bilateral.
When unilateral in spastic gait, the affected leg is held in extension and plantar flexion: and the ipsilateral arm is often flexed.
With spastic gait there is circumduction of the affected leg during the swing phase of each step.
Common causes of spastic gait include stroke or other unilateral lesions of the cerebral cortex .
If bilateral the spastic gait may appear stiff legged or scissoring going to increased tone in the adductor muscles such that the legs nearly touch with each step.
Common causes of bilateral spastic gait include cerebral palsy, cervical spondylytic myelopathy, multiple sclerosis accompanied by myelopathy such as bowel, bladder dysfunction, increased reflexes and Babinski signs.
Anti-spasticity agents such as baclofen or tizanidine are variably effective in improving gait but may reduce painful spasms, and botulinum toxin injections may be useful in cases of focal spasticity.
Scissors gait refers to a gait when legs bend inward. With this type, a person’s legs cross and may hit each other while walking. The crisscross motion may resemble scissors opening and closing.
Steppage gait occurs when a person’s toes point towards the ground while walking.
Often, the toes will scrape against the ground as the person steps forward.
Weakness of muscles of the lower extremities may manifest as a gait disorder such as a waddling gait.
The waddling gait is seen in cases of proximal muscle weakness, such as a myopathy.
In a normal gait the gluteal muscles stabilize the pelvis, elevating the nonweightbearing side with each step.
With weakness of the gluteal muscles and particularly the gluteus mediums, instability of the weight-bearing hip causes the non-weight-bearing side to drop and this is known as the Trendelenburg’s sign.
Waddling gait occurs when a person moves from side to side when walking.
Waddling involves taking short steps as well as swinging the body.
Propulsive gait is when a person walks with his or her head and neck pushed forward. It can appear as though the person is rigidly holding a slouched position.
A person with a limp is also considered to have an abnormal gait.
A limp may be either temporary or permanent.
Some of the most common causes of abnormal gait include:
injuries to the legs or feet
arthritis
infections in the soft tissue of the legs
broken bones in feet and legs
birth defects
infections in the inner ear
cerebral palsy
stroke
tendonitis
conversion disorder or other psychological disorders
shin splints
For abnormal gait, it is likely a person will use assistive devices for treatme can include:
leg braces
crutches
canes
walker
To prevent gait disturbances:
avoidance in participation in contact sports.
wearing of protective gear during sports.
wearing well-fitting footwear during physical activity.
wearing leg braces if needed.