The Kurtzke Expanded Disability Status Scale (EDSS)

# Overview
The Kurtzke Expanded Disability Status Scale (EDSS) is used as a measure of disease progression by assigning a severity score (0-10) to the patient's clinical status. Although the scale does not correspond linearly to common progression points for many patients, its widespread use and ease of implementation allow its utilization as a standardization measure for clinical trials .

# The EDSS Scale
- 0 - Normal neurologic examination (all grade 0 in functional systems ; cerebral grade 1 acceptable)
- 1 - No disability, minimal signs in one FS (ie, one grade 1 excluding cerebral grade 1)
- 1.5 - No disability, minimal signs in more than one FS (more than one grade 1 excluding cerebral grade 1)
- 2.0 - Minimal disability in one FS (one FS grade 2, others 0 or 1)
- 2.5 - Minimal disability in two FS (two FS grade 2, others 0 or 1)
- 3.0 - Moderate disability in one FS (one FS grade 3, others 0 or 1), or mild disability in three or four FS (three or four FS grade 2, others 0 or 1)
- 3.5 - Fully ambulatory but with moderate disability in one FS (one grade 3 and one or two FS grade 2) or two FS grade 3, others 0 or 1, or five FS grade 2, others 0 or 1
- 4.0 - Fully ambulatory without aid, self-sufficient, up and about some 12 hours a day despite relatively severe disability consisting of one FS grade 4 (others 0 or 1), or combinations of lesser grades exceeding limits of previous steps; able to walk without aid or rest some 500 meters (0.3 miles)
- 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 one 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 some 300 meters (975 ft)
- 5.0 - Ambulatory without aid or rest for about 200 meters (650 feet); disability severe enough to impair full daily activities (eg, to work a full day without special provisions); usual FS equivalents are one 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 about 100 meters (325 ft); disability severe enough to impair full daily activities; usual FS equivalents are one grade 5 alone, others 0 or 1, or combinations of lesser grades usually exceeding specifications for step 4.0
- 6.0 - Intermittent or constant unilateral assistance (cane, crutch, brace) required to walk about 100 meters (325 ft) with or without resting; usual FS equivalents are combinations with more than two FS grade 3+
- 6.5 - Constant bilateral assistance (canes, crutches, braces) required to walk about 20 meters (65 ft); usual FS equivalents are combinations with more than two FS grade 3+
- 7.0 - Unable to walk beyond about 5 meters (16 ft) even with aid, essentially restricted to wheelchair; wheels self in standard wheelchair a full day and transfers alone; up and about in wheelchair some 12 hours a day; usual FS equivalents are combinations with more than one 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 transfers, wheels self but cannot carry on in standard wheelchair a full day; may require motorized wheelchair; usual FS equivalents are combinations with more than one FS grade 4+
- 8.0 - Essentially restricted to bed or chair or perambulated in wheelchair; but may be out of bed 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 for much of the day; has some effective use of arm(s); retains some self-care functions; usual FS equivalents are combinations, generally grade 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 - Death due to MS

# Reference
-  Kurtzke JF: Rating neurologic impairment in multiple sclerosis: an expanded disability status scale (EDSS). Neurology 1983 Nov; 33(11): 1444-52