The purpose of testing lower extremity cerebellar function is to look for evidence of a lesion involving the cerebellar hemispheres or the cerebellar pathways.

The heel-to-shin maneuver, a simple screening test of lower extremity cerebellar function, should be performed on most patients as part of a standard neurologic examination. When cerebellar dysfunction is not suggested by the history or the preceding parts of the examination, however, it’s reasonable to stop the examination of cerebellar function after the (normal) finger-to-nose maneuver is completed. When there is a clinical suspicion for cerebellar dysfunction or to look for additional confirmation of cerebellar dysfunction when an abnormality is suggested on the upper extremity cerebellar examination (see Chapter 34, Testing of Upper Extremity Cerebellar Function), lower extremity cerebellar function should be tested.

Examination of gait, which should be a routine part of the neurologic examination, is discussed in Chapter 39, Examination of Gait.

The basic relevant neuroanatomy of the cerebellum and its pathways is discussed in Chapter 33, Approach to the Cerebellar Examination. The left cerebellar hemisphere coordinates the left leg (and arm), and the right cerebellar hemisphere coordinates the right leg (and arm). Table 33-1 summarizes the lesions within the cerebellum or its pathways that may cause incoordination on cerebellar testing.