Expanded Disability Status Scale

Expanded Disability Status Scale

Diagram of the Expanded Disability Status Scale

The Expanded Disability Status Scale (EDSS) is a method of quantifying disability in multiple sclerosis (MS) and monitoring changes in the level of disability over time. The scale was developed by John F. Kurtzke in 1983 and is widely used in clinical trials and in the assessment of patients with MS.

Description

The EDSS quantifies disability in eight Functional Systems (FS) and allows neurologists to assign a Functional System Score (FSS) in each of these. The FS include:

• Pyramidal (motor function)
• Cerebellar (coordination)
• Brainstem (speech and swallowing)
• Sensory (touch and pain)
• Bowel and bladder function
• Visual function
• Cerebral (mental) function
• Other

The EDSS score ranges from 0 to 10 in 0.5 increments, with 0 being normal neurological examination and 10 being death due to MS. Scores from 1.0 to 4.5 refer to people with MS who are fully ambulatory, while scores from 5.0 to 9.5 are defined by the impairment to ambulation.

Scoring

The scoring is based on a neurological examination and the patient's ability to walk. The scale is heavily weighted towards ambulation, with higher scores indicating greater disability:

• 0.0: Normal neurological exam
• 1.0-1.5: No disability, minimal signs in one FS
• 2.0-2.5: Minimal disability in one FS
• 3.0-3.5: Moderate disability in one FS
• 4.0-4.5: Significant disability but able to walk without aid
• 5.0-5.5: Disability severe enough to impair full daily activities
• 6.0-6.5: Requires a walking aid
• 7.0-7.5: Restricted to wheelchair
• 8.0-8.5: Restricted to bed or chair
• 9.0-9.5: Confined to bed, unable to communicate effectively
• 10.0: Death due to MS

Limitations

The EDSS is criticized for its emphasis on ambulation and its insensitivity to changes in other areas of disability, such as cognitive function. It may not fully capture the impact of MS on a patient's quality of life. Despite these limitations, it remains a standard tool in both clinical practice and research.

Related pages

• Multiple sclerosis
• John F. Kurtzke
• Functional Systems