EDSS

The Expanded Disability Status Scale, better known by its acronym EDSS, is the most widely used standardized neurological method for quantifying disability in patients with Multiple Sclerosis (MS). Developed by John Kurtzke in 1983, the scale allows clinicians to assess and monitor disease progression and a patient's level of functional impairment over time. The EDSS score ranges from 0 (normal neurological exam) to 10 (death due to MS), in half-point (0.5) increments. The scale is based on an assessment of eight Functional Systems (FS) of the central nervous system, which include pyramidal (muscle strength and movement), cerebellar (coordination and balance), brainstem (speech, swallowing, and eye movements), sensory (touch and pain), bowel and bladder functions, visual function, and mental (cerebral) functions. At the lower levels of the scale (0 to 4.5), the score is determined primarily by the degree of disability found in these Functional Systems while the patient is still fully able to walk (ambulatory). As the score increases, the scale becomes increasingly dependent on the patient's walking ability. For example, a score of 5.0 indicates disability that interferes with daily activities and limits walking to 200 meters without aid; 6.0 requires the use of a walking aid (such as a cane or crutch); 7.0 restricts the patient to a wheelchair; and the highest scores (8.0 to 9.5) describe patients confined to bed, with increasing dependence for basic care.