#7552 - The Cerebellar Examination - Medical Finals & OSCEs Notes

The Cerebellar Examination

General inspection

Truncal ataxia may mean that people sway whilst sitting, need support or fall over when sitting. They may have crutches, a frame or a wheelchair. The cerebellar problems may be ipsilateral or bilateral.

Gait

Wide, ‘broad-based’ balance as a sign of balance and coordination difficulty. They may need crutches. Walking heel-to-toe exaggerates the problem or makes it apparent and may even show dysmetria. They will probably not be able to walk heel-to-toe if severe. Deviation – leaning or falling – is towards the side of the lesion in cerebellar disease. They may turn on an axis, keeping one leg still and moving the other foot around to maintain balance.

Romberg’s

Will usually be void in a patient with cerebellar problems as they will be swaying at rest. It will also be dangerous to perform as they may fall over. Someone with ataxia who is steady at rest, then sways on standing, is Romberg’s positive and probably has proprioceptive or vestibular disease; this may mean that you should change the examination you are doing.

Face

Nystagmus is often seen. This is a combination of slow-phase smooth pursuit to the direction, usually of interest, with a fast-phase saccade to the opposite direction. A right-beating nystagmus has the fast phase to the right. In unilateral cerebellar disease the fast beat is towards the side of the lesion. It is large amplitude and low frequency. It may be to any direction and vertical or horizontal. It is usually a jerk nystagmus, as opposed to pendular. Square-wave jerks are inappropriate saccades that may be seen on looking at a fixed position.

Arms will probably be still at rest but will show an intention tremor with past-pointing, a manifestation of dysmetria, as they cannot judge depth. Someone with severe cerebellar syndrome will poke themselves in the eye if they are asked to touch their nose. Dysdiadochokinesia. When they are held out with eyes closed there is an exaggerated pendular rebound on movement due to lack of coordination of proprioception input and dysmetria. This also holds true for reflexes as there is a similar mechanism to intention tremor to getting the leg back to the first position. There is supposed to be hypotonia in cerebella disease but it is usually not obvious.

Legs will also show dysmetria, intention tremor, past pointing and dysdiadochokinesia.

Speech

There may be a stuttering staccato speech, with lack of coordination as seen with physical movements. Syllables may be individual and separate. Dysarthria may also be scanning, which means with sharp explosive bursts and no normal rhythm, jerkiness.

Writing may be larger than usual, apraxic agraphia, and also show signs of intention tremor and dysmetria.

Note that if there is a cerebello-pontine angle tumour there may well be cranial nerve signs such as eighth nerve (vestibulocochlear), fifth nerve and seventh nerve, even signs of neurofibromatosis type 2. Also there may be signs of other manifestations of the underlying pathology, such as multiple sclerosis or alcoholism.

Examination in brief overview

• Inspection

  • Truncal ataxia

• Walk

  • Broad-based gait

  • Lean or fall to the side of the lesion

• Turn

  • Turn on an axis

• Heel-to-toe

  • ...