Medical aspects of fitness to drive a guide for medical practitioners

2.7
Progressive neurological disorders
(including Parkinsonism, multiple sclerosis
and motor neurone disease)
All forms of severe neuromuscular disease will affect an individual’s ability to control
a motor vehicle safely as a result of weakness, stiffness, slowed responses and
incoordination. In addition, multiple sclerosis may also cause visual problems, vertigo
and sensory loss that will further complicate the picture. Medical practitioners should
check for limb strength, accuracy of rapid foot movements and joint proprioception.
Medical practitioners should also be alert to cognitive impairments that may coexist
with conditions such as Parkinson’s disease.
Where driving may resume or may occur
Individuals with very minor muscular weakness may drive if they have a full
assessment, including off‐road and on‐road assessments of driving skills, that shows
that they can drive safely. Regular reassessments may be required as a condition of
holding a licence.
A further exception may be made in cases of drug‐induced Parkinsonism, provided that
an individual is likely to make a full recovery on cessation of treatment and provided
that the reason for the therapy is not a cause of exclusion in its own right.
Medical standards for individuals applying for or renewing a class 1 or class 6 licence and/or
a D, F, R, T or W endorsement (see appendix 3)
When driving should cease
Driving should cease in all cases in which there is any doubt about an individual’s
ability to control a vehicle in an emergency or other situation in which rapid responses
may be needed. If an individual has difficulty walking, they may also be unfit to drive.
When driving may resume or may occur
In the early stages of these conditions, it will often be possible to drive effectively,
but there will inevitably come a time when driving is no longer safe. The medical
practitioner will often have to make a difficult decision in these circumstances, perhaps
aided by a relevant specialist. Assessments from occupational therapists with training
in driver assessment, as well as practical driving tests, will often be required before
making a final decision on fitness to drive.
An additional problem is that, in conditions such as multiple sclerosis, there is a
variable and intermittent progression with periods of significant remission. It may be
necessary to limit individuals from driving at certain periods and allow them to drive
only during periods of remission.
Licence conditions may include regular reassessments, such as an annual medical report.
Medical standards for individuals applying for or renewing a class 2, 3, 4 or 5 licence and/or
a P, V, I or O endorsement
When driving should cease
Individuals with these conditions should not drive.
30 2. Neurological and related disorders | Medical aspects of fitness to drive | NZTA July 2009
July 2009 NZTA | Medical aspects of fitness to drive | 2. Neurological and related disorders 31