The Expanded Disability Status Scale (EDSS)
The EDSS is the most commonly used scale. The EDSS can help physicians monitor changes in the level of disability over time. It is widely used in clinical trials and in the assessment of people with MS. The EDSS focuses mainly on your ability to walk. In general, the EDSS can be broken down like this:
0 = Normal
1-1.5 = No disability, but some abnormal neurological signs
2-2.5 = Minimal disability
3-4.5 = Moderate disability, affecting daily activities, but a patient can still walk
5-8 = More severe disability, impairing one’s daily activities and requiring assistance with walking
8.5-9.5 = Very severe disability, restricting a patient to bed
10 = Death
Ambulation Index (AI)
MS doctors may also assess a patient’s AI.
0 = Asymptomatic; fully active.
1 = Walks normally but reports fatigue which interferes with athletic or other demanding activities.
2 = Abnormal gait or episodic imbalance; gait disorder is noticeable to family and friends.Able to walk 25 feet in 10 seconds or less.
3 = Walks independently; able to walk 25 feet in between 11-20 seconds
4 = Requires unilateral support (cane, single crutch) to walk. Walks 25 feet in 20 seconds or less.
5 = Requires unilateral support but walks 25 feet in greater than 20 seconds or requires bilateral support (canes, crutches, walker) and walks 25 feet in 20 seconds or less
6 = Requires bilateral support and walks 25 feet in greater than 20 seconds. (May use wheelchair on occasion)*
7 = Walking limited to several steps with bilateral support; unable to walk 25 feet. (May use wheelchair most of the time)
8 = Restricted to wheelchair; able to transfer independently.
9 = Restricted to wheelchair; unable to transfer independently.
10 = Bedridden.
Disease Steps
MS Doctors also think of the overall disease step and how this evolves over time.
0= Normal – Functionally normal; no limitations on activity or lifestyle; RR; EDSS=0-1.5; AI=0; may have minor abnormality on exam (eg nystagmus, extensor plantar); attack frequency <1/year; return to baseline with/without treatment and generally not treated.
1 = Mild Disability – Minor, but noticeable signs and/or symptoms (eg. sensory symptoms, minor bladder problems, fatigue);RR or very early CP; EDSS=2-2.5; AI=0-1 (ie-no visible abnormality of gait); attack frequency=1-2/year.
2 = Moderate Disability – Main feature=abnormality of gait; AI=2-3; EDSS=2-4.5; able to work full day, but may find athletic activities difficult; RR-P or early CP; may need cane with attack but recover to independent ambulation.
3 = Early Cane – EDSS=6; RR-P or CP; AI=2-3; may use a cane/unilateral support (eg spouse’s arm) outside for greater distances, but can walk 25 feet in 20 seconds or less without a cane.
4 = Late Cane – EDSS=6; RR-P or CP; AI=4-5; unable to walk 25 ft. without a cane/unilateral support(eg may hang on to furniture inside home or touch wall in clinic; use cane outside; may need a scooter for greater distances (eg in malls).
5 = Bilateral Support – EDSS=6.5; AI=5-6; require bilateral support to walk 25 feet (eg 2 canes or crutches or walker); may use a scooter for greater distances.
6 = Wheelchair – EDSS > 7; AI > 7; confined to wheelchair; may be able to take 1 or 2 steps, but cannot ambulate 25 feet even with bilateral support; may have further progression including problems with use of hands, inability to transfer.
U = Unclassifiable – Used for patients who do not fit above classification; eg-significant cognitive or visual impairment.
MS Progression: Multiple Sclerosis Functional Composite (MSFC)
The MSFC is a newer measurement system. It is sensitive to changes other than mobility. The MSFC often takes a bit more time to complete, so it is currently used less in clinic and more in clinical trials.
The MSFC measures the following:
- Walking speed, using a timed 25-foot walk
- Arm and hand dexterity, using a nine-hole peg test
- Cognitive function, such as how well a patient can do math calculations, using the Paced Auditory Serial Additions Test (PASAT)
Functional Status
Pyramidal Function
O
Normal
1
Abnormal signs without disability
2
Minimal disability
3
Mild or moderate paraparesis or hemiparesis; severe monoparesis
4
Marked paraparesis or hemiparesis; moderate quadriparesis; or monoplegia
5
Paraplegia, hemiplegia, or marked quadriparesis
6
Quadriplegia
Cerebellar function
Normal
Abnormal signs without disability
Mild ataxia
Moderate truncal or limb ataxia
Severe ataxia all limbs
Unable to do coordinated movements due to ataxia
Is used after each number when weakness (grade 3 or more on pyramidal) interferes with testing
Brainstem Function
Normal
Signs only
Moderate nystagmus, or other mild disability
Severe nystagmus, marked extraocular weakness, or moderate disability of other cranial nerves
Marked dysarthria or other marked disability
Inability to swallow or speak
Sensory function
Normal vibration (VIB)/position sense (PS)
Mild l VIB in 1 or 2 limbs; PS normal
Moderate l VIB &/or mild l PS in 1 or 2 limbs OR mild l VIB in 3 or 4 limbs; PS normal
Lost VIB &/or moderate l PS in 1 or 2 limbs OR moderate l PS in 3 or 4 limbs
Lost PS in 1 or 2 limbs OR severe l PS in 3 or 4 limbs
Lost PS in 3 or 4 limbs
Sensation lost below the head
Bowel and bladder function
Normal
Mild hesitancy, urgency, or retention
Moderate hesitancy, urgency, or retention, or rare urinary incontinence
Frequent incontinence
In need of almost constant catheterization
Loss of bladder control
Loss of bowel and bladder control
Visual function (best corrected)
Normal
Scotoma with acuity better than 20/30
Worse eye=20/30-20/59
Worse eye=20/60-20/99
Worse eye=20/100-20/200 OR #3 + better eye worse than or=to 20/60
Worse eye less than 20/200 OR #4 + better eye worse than or=to 20/60
#5 + better eye worse than or=to 20/60
Mental Function
Normal
Mood alteration only (does not affect EDSS score)
Mild decrease in mentation
Moderate decrease in mentation
Marked decrease in mentation
Dementia – severe or incompetent
Right Hand Function (not included in EDSS)
Normal
Mild-minor problems with coordinated tasks
Moderate-unable to write clearly
Severe-unable to feed self
Left Hand Function (not included in EDSS)
Normal
Mild-minor problems with coordinated tasks
Moderate-unable to write clearly
Severe-unable to feed self
