A 34-year-old man comes to your office because he is "having a hard time walking." Two weeks ago, he noticed "weakness" in his right leg that has changed the way he walks.
- What additional questions would you ask to characterize his gait abnormality?
- What are the 5 physiologic components essential to normal ambulation?
- Can a definitive cause of his gait abnormality be determined by historical information alone?
- What historical questions will be useful in determining the appropriate evaluation of his gait abnormality?
Ambulation (gait) is an exercise in controlled falling. The upright body falls forward and the outstretched foot and leg must prevent the body from falling by supporting the body's weight and rotating the weight over the limb. Gait abnormalities result from 1 of 5 disorders:
Inadequate muscle strength to flex the hip (to raise the knee), flex the knee (to lift the foot), or dorsiflex the ankle (to keep the foot from dragging on the ground).
Inadequate sensation in the foot (or excess sensation with neuropathies) to tell the brain when the foot has planted and is ready for the body to rotate over the limb.
Inadequate muscle strength in the leg to maintain extension of the leg (knee) to support the body's weight.
Inability to relax the muscles of the leg as the body moves over the extended leg and transfers weight to the opposite leg (in preparation for extending the leg for the next step).
Disorders of the cerebellum, which normally receives sensory input and coordinates muscle contraction (the stepping limb) and relaxation (the opposite limb).
|Ataxia||Unbalanced or uncoordinated ambulation.|
|Cerebellar ataxia||Ataxia due to impaired cerebellar function.|
|Normal-pressure hydrocephalus||A triad of dementia, ataxia, and urinary incontinence that results from obstruction of the arachnoid granulations that drain cerebrospinal fluid. The fluid accumulation compresses the brain, causing the symptoms.|
|Peripheral neuropathy||Abnormal sensory or motor nerve function leading to weakness, altered sensory perception, or both.|
|Sensory ataxia||Ataxia due to impaired proprioceptive or sensory feedback from the lower extremities.|
|Spastic paraplegia||Tonic muscular contraction leading to an inability to relax the muscles. The increased tone is due to damage of the inhibitory neurons in the spinal cord or brain.|
Gait disorders result from disease of muscles, nerves, bones and joints, or the cerebellum.
- Review the patient's past medical history. Most gait abnormalities are due to chronic or congenital diseases.
- Assess the time course of the symptoms. Acute changes in gait suggest an injury or stroke. A gradual, protracted onset suggests a systemic disease, peripheral neuropathy, or cerebellar disease of any type.
- Avoid leading questions. It may be necessary to follow-up with a close-ended questions directed at the most likely disorder.
- Assess for alarm symptoms.
- Ask about conditions that make the gait abnormality worse (ie, walking in darkness or walking upstairs).
- Ask about weakness involving ...