Gait, Cerebellar Function, and Movement Disorders

Question 1

List the essentials for normal walking.

Answer 1

1. Strength in the lower limbs and trunk (UMNs, LMNs, NMJs, muscles)
2. Coordination and postural control (cerebellar and extrapyramidal systems)
3. Intact sensation (especially proprioception)
4. Memory/concept of walking (gait apraxia)

Question 2

What does the Romberg sign indicate?

Answer 2

Impaired proprioception (posterior or dorsal column pathways or their afferent sensory nerves)

Question 3

Causes of broad-based gait ataxia?

Answer 3

Lesions of the posterior columns or proprioceptive sensory nerves (worse with eyes closed) or cerebellar dysfunction (always present)

Question 4

Appearance and cause of hemiplegic gait?

Answer 4

Affected lower limb is stiffly extended and swung or circumducted when walking while the ipsilateral upper limb is flexed at the elbow and wrist with decreased arm swing; stroke

Question 5

Appearance and cause of tabetic gait?

Answer 5

Foot slapping characteristics (compensating for impaired sensation in the feet by forcibly planting the feet down to feel the floor); tabes dorsalis from neurosyphilis

Question 6

Appearance and cause of steppage gait?

Answer 6

Foot drop or weak dorsiflexion of the foot; to prevent tripping over the toes when walking, the hip is flexed or pulled up even higher to elevate the drooping foot, which is then lowered to the floor toe first

Unilateral foot drop - lesion of peroneal nerve or L5 nerve root

Bilateral foot drop - severe polyneuropathy, motor neuron disease, bilateral L5 root lesions

Question 7

Appearance and cause of duck waddle/waddling gait?

Answer 7

Patient leans or bends the trunk to the left as the right foot is raised and vice versa, alternately tilting the pelvis and hips side to side like a walking duck

Weakness of the hip girdle muscles, usually seen in muscle disease (myopathy)

Question 8

Appearance and cause of scissors gait?

Answer 8

Advancing leg or foot tends to cross over the opposite lower limb

UMN (CST) lesion -> spasticity in the lower limbs, including the adductor muscles of the thighs

Question 9

Appearance of parkinsonian gait?

Answer 9

Slow and shuffling with decreased armswing and bent over posture; may exhibit festination

Question 10

Tests of cerebellar function?

Answer 10

Finger-nose-finger
Heel-shin-knee
Rapid alternating movements

Question 11

What is dysmetria?

Answer 11

Overshooting or undershooting of the target by the hand or foot in cerebellar testing

Question 12

What is dysdiadochokinesia?

Answer 12

Uncoordinated, non-rhythmic sloppy hand movements in rapid alternating movement testing

Question 13

What is a rebound phenomenon?

Answer 13

Cerebellar deficits in upper limbs create an imbalance between agonist and antagonist muscles - patient contracts biceps muscle against the examiner’s efforts. If the examiner suddenly lets go, normally the patient’s triceps reflexively contract to stop the unopposed elbow flexion. If there is cerebellar disease, the persisting elbow flexion may cause the patient to stroke his or her chest or face.

Question 14

What is cerebellar dysarthria?

Answer 14

Slurred speech associated with involvement of the left cerebellar hemisphere; speech is less distinct, “thick,” erratic, jerky, or explosive; syllables are broken down or hyphenated with non-rhythmic or unequal emphasis or force

Question 15

What type of eye movements can occur in cerebellar disease?

Answer 15

Multidirectional nystagmus (may also occur with lesions of othe vestibular system and brain stem)

Question 16

Presentation of cerebellar hemisphere lesion?

Answer 16

Affects ipsilateral limbs causing kinetic tremor, limb dysmetria, dysdiadochokinesia, and rebound phenomenon

Question 17

Causes of unilateral cerebellar hemispheral lesions?

Answer 17

Ischemic infarction, hemorrhage, tumor, MS

Question 18

Causes of bilateral cerebellar hemisphere lesions?

Answer 18

Degenerative or toxic diseases

Question 19

Presentation of a cerebellar lesion in the vermis?

Answer 19

Truncal unsteadiness while standing or walking, with impaired balance and gait ataxia

Question 20

Causes of cerebellar vermis lesions?

Answer 20

HHemorrhage, tumor, MS, degenerative or toxic disorders (alcohol in particular)

Question 21

What is the most common spinocerebellar degeneration or ataxia?

Answer 21

Friedreich’s ataxia

Question 22

Presentation of Friedreich’s ataxia?

Answer 22

AR disorder
Begins in school-age children and gradually worsens
Spinocerebellar tract lesions (patchy loss of cerebellar Purkinje cells) -> limb dysmetria, gait ataxia, and dysarthria
CST lesions -> weakness and Babinski signs
Dorsal root ganglia/dorsal or posterio columns -> loss of vibration, position sense, and absent reflexes in the lower limbs
Other features: scoliosis, pes cavus, cardiac hypertrophy, potentially fatal cardiac arrhythmias

Question 23

Diagnose Friedrich’s ataxia?

Answer 23

Blood test revealing multiple trinucleotide repeats from a defect in chromosome 9

Question 24

What are hyperkinesias?

Answer 24

Spontaneous, involuntary movements with characteristic clinical features

Question 25

What is a tremor?

Answer 25

Spontaneous, rhythmic, oscillatory movement of hands, limbs, head, or voice

Question 26

A resting tremor is typical of ___.

Answer 26

Parkinson’s disease

Question 27

What is a postural tremor?

Answer 27

More obvious tremor when the limbs are maintained in various positions, such as holding an object or extending an arm or leg

Question 28

What is a kinetic tremor?

Answer 28

Primarily occurs in a limb moving towards a target or performing a task

Question 29

Postural and kinetic tremor without other neurological signs or symptoms is often due to ___.

Answer 29

Familial essential tremor

Question 30

Kinetic tremor may be caused by ___.

Answer 30

Cerebellar disease

Question 31

What is athetosis?

Answer 31

Slow, writhing, fairly continuous movements of the distal limbs

Question 32

What is chorea?

Answer 32

Purposeless, random, non-rhythmic movements of the limbs, face, neck, and trunk

Question 33

Cause of choreoathetosis?

Answer 33

Lesions in the caudate nucleus or its connecting pathways (eg, Huntington’s disease)

Question 34

What is hemiballismus?

Answer 34

Rapid, violent, flinging movements of the proximal limbs on one side

Question 35

Cause of hemiballismus?

Answer 35

Lesion in the contralateral subthalamic nucleus (usually an ischemic infarction)

Question 36

What is dystonia?

Answer 36

Continual, sustained, often painful contraction of muscles leading to spasms, turning, and twisting of the limbs, neck, head, or trunk into unnatural positions or fairly fixed postures

Question 37

What are tics?

Answer 37

Stereotyped, often repetitive, focal muscle contractions that appear semipurposeful, such as an eyeblink, facial twitch, or sniff

Question 38

What are two movement disorders which accompany encephalopathy?

Answer 38

Myoclonus and asterixis

Question 39

What is myoclonus and what causes it?

Answer 39

Rapid, shocklike, lightning movements or jerks of the limbs and trunk, which is usually bilateral but asynchronous and irregular

May be seen in Cretzfeldt-Jakob

Question 40

What is asterixis?

Answer 40

Semirhythmic loss of postural control of hands and feet, so that the extended hands or feet appear to have a “flapping tremor”

If unilateral - structural brain disease such as ischemic infarction

Question 41

Rx resting tremor of Parkinson’s disease?

Answer 41

Anticholinergics (if isolated or predominant)
Levodopa and dopamine agonists if other parkinsonian symptoms

Severe cases - deep brain stimulation to the sub-thalamus

Question 42

Rx essential tremor?

Answer 42

Beta-adrenergic blocker drugs; barbiturates

Severe cases - deep brain stimulation to the thalamus

Question 43

Rx choreoathetosis, hemiballismus, tics

Answer 43

Dopamine antagonists

Question 44

Rx dystonia?

Answer 44

Anticholinergics, benzos, botulinum toxin injections