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Neurological
Assessment
History: Patients with
MS initially have a difficult time describing their symptoms, as the symptoms
appear and subsequently resolve. The sine qua non of MS is that the symptoms are
separated in time and space. These symptoms affect different parts of the body
at different times. Patients may present with paresthesias of a hand that
resolves, followed in a couple of months by weakness in a leg or visual
disturbances (eg, diplopia). Patients frequently do not bring these complaints
to their doctors because they resolve. Eventually, the resolution of the
neurologic deficits is incomplete or their occurrence is too frequent, and the
diagnostic dilemma begins.
Physical: Patients with MS may demonstrate
various physical findings. These findings may change from examination to
examination, depending on the pattern of disease and whether or not the patient
is having an exacerbation or relapse.
- A thorough physical examination, including neurologic
assessment, is critical to determine deficits. All systems must be
addressed, including motor, sensory, and musculoskeletal, as well as
reflexes, tone, coordination, bulbar, vision, gait, and skin.
- Some of the findings may include localized weakness,
focal sensory disturbances (with persistent decrease of proprioception and
vibration), hyperreactive reflexes with clonus in the ankles and upgoing
toes, and increased tone or stiffness in the extremities with
velocity-dependent passive range of motion (PROM).
- Additional signs may include the following: nystagmus,
internuclear ophthalmoplegia, visual disturbances, pallor of the optic
disc, poor coordination of upper and lower extremity movements, and
wide-based gait with inability to tandem walk.
- Secondary problems may include skin breakdown and
musculoskeletal complaints. Skin should be examined in all nonambulatory
patients, and the musculoskeletal system must be addressed as appropriate.
- Based on the findings, a patient may be rated according to
several clinical scales. The most widely accepted clinical rating scale is
the 10-point Kurtzke Expanded Disability Status Scale (EDSS), developed
originally in 1955 as the Disability Status Scale (DSS). See Table 1.
Table 1. Expanded Disability Status Scale
| Grade |
Definition |
| 0 |
Normal neurologic examination (all grade 0 in FS,
cerebral grade 1 acceptable) |
| 1.0 |
No disability, minimal signs in 1 FS (ie, grade 1
excluding cerebral grade 1) |
| 1.5 |
No disability, minimal signs in more than 1 FS (more
than 1 grade 1 excluding cerebral grade 1) |
| 2.0 |
Minimal disability in 1 FS (1 FS grade 2, others 0 or
1) |
| 2.5 |
Minimal disability in 2 FS (2 FS grade 2, others 0 or
1) |
| 3.0 |
Moderate disability in 1 FS (1 FS grade 3, others 0 or
1) or mild disability in 3 or 4 FS (3/4 FS grade 2, others 0 or 1)
though fully ambulatory |
| 3.5 |
Fully ambulatory but withmoderate disability in 1 FS (1
grade 3) and 1 or 2 FS grade 2, or 2 FS grade 3, or 5 FS grade 2 (others
0 or 1) |
| 4.0 |
Fully ambulatory without aid; self-sufficient; up and
about some 12 h/d despite relatively severe disability, consisting of 1
FS grade 4 (others 0 or 1) or combinations of lesser grades exceeding
limits of previous steps; able to walk without aid or rest approximately
500 m |
| 4.5 |
Fully ambulatory without aid; up and about much of the
day; able to work a full day; may otherwise have some limitation of full
activity or require minimal assistance; characterized by relatively
severe disability, usually consisting of 1 FS grade 4 (others 0 or 1) or
combinations of lesser grades exceeding limits of previous steps; able
to walk without aid or rest for approximately 300 m |
| 5.0 |
Ambulatory without aid or rest for approximately 200 m;
disability severe enough to impair full daily activities (eg, to work
full day without special provisions; usual FS equivalents are 1 grade 5
alone, others 0 or 1; or combinations of lesser grades usually exceeding
specifications for step 4.0) |
| 5.5 |
Ambulatory without aid or rest for approximately 100 m;
disability severe enough to preclude full daily activities (usual FS
equivalents are 1 grade 5 alone; others 0 or 1; or combinations of
lesser grades usually exceeding those for step 4.0) |
| 6.0 |
Intermittent or unilateral constant assistance (cane,
crutch, or brace) required to walk approximately 100 m with or without
resting (usual FS equivalents are combinations with more than 2 FS grade
3+) |
| 6.5 |
Constant bilateral assistance (canes, crutches, or
braces) required to walk approximately 20 m without resting (usual FS
equivalents are combinations with more than 2 FS grade 3+) |
| 7.0 |
Unable to walk beyond approximately 5 m even with aid;
essentially restricted to wheelchair; wheels self in standard wheelchair
and transfers alone; up and about approximately 12 h/d (usual FS
equivalents are combinations with more than 1 FS grade 4+; very rarely,
pyramidal grade 5 alone) |
| 7.5 |
Unable to take more than a few steps; restricted to
wheelchair; may need aid in transfer; wheels self but cannot carry on in
standard wheelchair a full day; may require motorized wheelchair (usual
FS equivalents are combinations with more than 1 FS grade 4+) |
| 8.0 |
Essentially restricted to bed or chair or perambulated
in wheelchair but may be out of bed itself much of the day, retains many
self-care functions; generally has effective use of arms (usual FS
equivalents are combinations, generally grade 4+ in several systems) |
| 8.5 |
Essentially restricted to bed much of the day; has some
effective use of arms; retains some self-care functions (usual FS
equivalents are combinations, generally 4+ in several systems) |
| 9.0 |
Helpless bed patient; can communicate and eat (usual FS
equivalents are combinations, mostly grade 4+) |
| 9.5 |
Totally helpless bed patient; unable to communicate
effectively or eat/swallow (usual FS equivalents are combinations,
almost all grade 4+) |
| 10.0 |
Death due to MS |
- These criteria have been revised over the years and remain
the standard scale by which patients may be compared. The scale ranges from
0-10 in 0.5 increments. The scores from grades 0-4 are derived from
Functional System (FS) scales that evaluate dysfunction in 8 neurologic
systems, including pyramidal, cerebellar, brainstem, sensory, bladder and
bowel, vision, cerebral, and "other."
- Advantages of this scale are that it is widely used
clinically, is easy to administer, and requires no special equipment.
- Limitations of the EDSS are that it (1) is heavily
dependent on mobility; (2) is somewhat subjective in certain areas (eg,
bowel and bladder function); (3) is insensitive to small changes; and (4)
does not present an accurate picture of the patient’s cognitive
abilities and functional abilities in performing activities of daily
living (ADL).
- Additional useful scales include the Ambulation Index,
which is based solely on the ability to walk 25 feet, and the Scripps
Neurologic Rating Scale, developed by Sipe in 1984. This scale has a finer
incremental scale than the Kurtzke scale, but it is not widely accepted and
does not consider cognitive involvement.
Causes: The cause of MS is not known. Both
environmental factors and a genetic predisposition, which affect an individual's
chance of acquiring the disease, appear to play a role.
- Identical twin studies have shown up to a 60% risk of one
twin's developing MS if the other is affected. The first-degree family
members (children or siblings) of people affected with MS have a 3-5% risk
of developing MS.
- Geography is clearly an important factor in the equation.
Persons from the equatorial regions of the world have a much lower incidence
than those in the southernmost and northernmost regions. If an individual
lives in an area with low incidence of MS until age 15 years, that person's
risk is low; however, if an individual lives in an area with a high
incidence until age 15 years, the risk of developing MS is high. The
interesting point is that, if that person moves to an area of high incidence
from an area of low incidence after age 15 years, the person does not have
increased risk beyond the area from which he or she moved. It appears that
whatever environmental factor is involved, it must exert its effect in early
childhood. Certain ethnic groups (eg, Eskimos), despite living in areas of
higher incidence, do not have high incidence of MS. Therefore, the exact
role played by geography versus genetics in incidence of the disease is not
clear.
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