A 46-year-old man is being evaluated for a gait disorder. He was referred by social workers due to frequent falls. His symptoms began gradually about a year ago and have become progressively worse. The patient's history is notable for alcohol use disorder, and he is currently experiencing homelessness, with sporadic stays in a nearby shelter. On examination, he has a broad-based, unsteady gait. A single tap on his patellar tendon elicits persistent, slow, back-and-forth swinging of the leg. Nystagmus and truncal ataxia are also present. Which of the following additional findings would most likely be seen in this patient?

Question

A 46-year-old man is being evaluated for a gait disorder.  He was referred by social workers due to frequent falls.  His symptoms began gradually about a year ago and have become progressively worse.  The patient's history is notable for alcohol use disorder, and he is currently experiencing homelessness, with sporadic stays in a nearby shelter.  On examination, he has a broad-based, unsteady gait.  A single tap on his patellar tendon elicits persistent, slow, back-and-forth swinging of the leg.  Nystagmus and truncal ataxia are also present.  Which of the following additional findings would most likely be seen in this patient?

Quizplus · Accepted Answer

11ec25c8_d59b_ffb8_bc81_8d031a091b88_MD0003_00 This patient has evidence of cerebellar dysfunction in the setting of likely alcoholic cerebellar degeneration. Typical features include progressive gait dysfunction, truncal ataxia, and nystagmus. Patients often have evidence of postural incoordination (eg, inability to tandem walk, abnormal heel-knee-shin testing) with relatively preserved limb coordination (normal finger-nose testing). Muscle hypotonia can also be present, leading to a pendular knee reflex - persistent swinging movements of the limb after eliciting the deep-tendon reflex (more than 4 swings is considered abnormal). Pendular reflexes are not brisk, unlike clonus, which would suggest pyramidal tract disease. At later stages, patients may develop a postural tremor of the fingers and thighs, dysarthria, and visual problems (eg, diplopia). (Choice A) A Babinski sign is an upward deviation of the great toe when the sole of the foot is stroked. It is evidence of hyperreflexia and suggests an upper motor neuron lesion. It is not characteristic of cerebellar disease. (Choice B) Bradykinesia, a general slowing of movement, is a hallmark of Parkinson disease. Parkinson disease is also characterized by resting tremor, rigidity, and postural instability. Deep-tendon reflexes are generally normal. (Choice C) The "clasp knife" phenomenon refers to a velocity-dependent resistance to passive movement of the limb. It is seen in patients with hypertonia due to pyramidal tract disease and is not characteristic of cerebellar disease. (Choice D) Thyroid disorders can affect deep-tendon reflexes and muscle tone, as well as general cognitive function. Specific features of cerebellar dysfunction, such as ataxia or intention tremor, are uncommon. (Choice E) Disorders affecting the inner ear and vestibulocochlear nerve can cause hearing loss and gait instability. The most common causes include trauma, infection, and Ménière disease. Neoplasms of the cerebellopontine angle (eg, acoustic schwannoma) can cause cerebellar dysfunction, vestibular dysfunction, and hearing loss. Alcoholic cerebellar degeneration, which is not associated with hearing loss, is more likely in this patient. Educational objective: Cerebellar dysfunction is common among patients with alcohol use disorder. Manifestations include gait instability, truncal ataxia, and postural incoordination. References: Mechanisms of ethanol-induced degeneration in the developing, mature and aging cerebellum. (http://www.ncbi.nlm.nih.gov/pubmed/18418667)

A 46-Year-Old Man Is Being Evaluated for a Gait Disorder