John Kurtzke developed a scale for measuring the severity of disability. The 1-10 scale is the most widely used systems for clinically judging the status of people with MS. The Expanded Disability Status Scale is also useful in measuring the efficacy of treatments in clinical trials.

The Expanded Disability Status Scale (EDSS) is a 0-10 scale, which provides a measurement for disability in MS and is a widely used standard for the clinical assessment of MS. It is employed by neurologists to track individual disease progression and as a benchmark in clinical trials.

The EDSS allows neurologists to assign a Functional System Score (FSS) to eight Functional Systems (FS) of the body that are affected by MS: pyramidal, cerebellar, brainstem, sensory, bowel and bladder, visual, cerebral, and other.

0.0 Normal neurological exam

1.0 No disability but at least one abnormal sign

1.5 No disability but more than one abnormal sign

2.0 Mild disability in at least one system

2.5 Mild disability in at least one system and minimal disability in 2 systems

3.0 Moderate disability in at least one system and mild disability 3-4 other systems

3.5 Fully mobile but moderate disability in one system and mild disability in others

4.0 Fully mobile without aid (with rest after 500 meters) and independent despite severe disability

4.5 Fully mobile without aid (with rest after 300 meters) & independent despite severe disability. May require some
assistance on activities

5.0 Fully mobile without aid (with rest after 200 meters) & disability may affect daily activities, requiring assistance

5.5 Fully mobile without aid (with rest after 100 meters). Disability influences daily activity.

6.0 Need a single cane, crutch, or brace in order to walk

6.5 Needs two canes, two crutches, or two braces in order to walk. Able to move 100 meters without rest

7.0 May be able to take a few steps but needs a wheelchair for mobility. Able to wheel self & transfer from wheelchair
independently

7.5 Need wheelchair for mobility. May need aid to transfer and may need a motorized wheelchair

8.0 Restricted to bed or limited time in a motorized wheelchair. Retains use of arms & performs self-care functions

8.5 Restricted to bed but performs self-care functions with limited use of arms

9.0 Confined to bed but able to communicate and eat

9.5 Immobile and unable to communicate or swallow

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