On the other hand, one should not assume that a patient who manifests a disorder of gait or inability to walk but no other neurologic abnormality necessarily has a psychogenic disorder. Lesions that are restricted to the anterosuperior cerebellar vermis may cause an ataxia or severe instability that becomes manifest only when the patient attempts to stand and walk; this is also true of very advanced NPH, frontal lobe disease, and various intoxications such as with alcohol or antiepileptic medications. Cases of severe peripheral neuropathy, particularly if there is prominent sensory loss, may also greatly impair the ability to stand or walk, and the unusual condition of orthostatic leg tremor (see the chapter on disorders of movement) that may produce buckling of the legs when the patient stands for some period of time, a situation often mistaken for hysteria. Similarly, the combination of ataxia and stiffness of the legs and buttocks that characterizes stiff-person syndrome may be easily mistaken for a psychogenic disorder.
Once the gait abnormality has been characterized, one should explore the possibility of rehabilitation by a combination of medical therapy and other corrective measures. The antispasticity agents baclofen and tizanidine are somewhat helpful when stiffness of the limbs exceeds weakness. They may reduce spasticity of the legs, but sometimes at the expense of exposing, to a greater degree than before, a loss of muscle power—the net effect being to the patient’s disadvantage. In extreme cases, a subarachnoid pump infusion of baclofen may be effective for spasticity.
Hypofunction of the labyrinths, as in drug-induced or idiopathic vestibulopathy, has greatly challenged physiatrists. Balance training and attention to postural correction and vision have helped some of these patients to be more steady and better able to function (see Baloh and Honrubia). Vestibular sedatives (e.g., meclizine) should be discontinued. Exercises to strengthen leg muscles can be beneficial in many circumstances, as can weight loss. Likewise, gait ataxia from proprioceptive defects can probably be corrected to some extent by careful attention to visual control and proper placement of the feet. Once dementia becomes conjoined with any of the gait disorders that occur in advanced age or with frontal lobe disease, rehabilitation stands less chance of success, since the ability to attend to small changes in terrain and posture is lost. Many patients have found exercises that emphasize balance, such as tai chi an yoga, to be helpful. Progression from the use of a cane, to a pronged cane, and finally to a four-posted walker allows patients with all types of gait disorders to maintain some mobility. The optimal use of these orthoses is best directed by experienced physical therapists and physiatrists.
Gait training with encouragement has been a useful maneuver to improve psychogenic gait disorders but some prove resistant.
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