Table 4.

Clinicians use scoring systems to categorise the severity of different conditions. Often different classifications arise as different groups come up with their own systems; however, international consensus groups usually choose one system to standardise publications and treatments across the board. This has not been the case with DCM. Several different systems are still been used by different authors based on their preference. The following are the most common classification systems currently in use, along with a guide to their score meaning, presence of radiologic features, short-comings and advantages. Showcasing the complete classifications is beyond the scope of this review. To obtain the complete scoring systems, please follow the link to the reference [15,47,48,49].

Name	Scoring Method	Radiologic Findings	Correlation to Symptoms	Limitations	Advantages
Nurick	0–5. The higher the grade, the more severe the deficit.	No	Affected by gait function (++), lower limbs paresis and paraesthesia and vegetative symptoms (+).	Less accurate post-op scoring; Does not pick up upper extremity disfunction	Evaluates economic situation in connection to gait function.
mJOA	0–17. The lower the score, the more severe the deficits. Normal: 16–17, grade 1: 12–15, grade 2: 8–11, grade 3: 0–7. Upper extremity 23.5%; lower extremity 23.5%; sensory 35.4%; bladder and bowel 17.6%	No	Affected by paraesthesia of lower limbs and paresis of upper limbs (++) and dysdiadochokinesia and vegetative symptoms (+).	Does not take economic factors into consideration	Good for assessing outcomes (post-intervention).
CMS	Upper and lower extremity are analysed separately. 0–5 each. The higher the grade, the more severe the deficit.	Weak correlation between low severity in the lower limb score and C-Spine mal-alignment	Affected by dysdiadochokinesia, gait function and paresis of upper extremity (++) and vegetative symptoms (+)	Does not take economic factors into consideration	Good for assessing function/symptoms of upper/lower extremities/as it evaluates them individually. Good at assessing clinical state and grade of severity of CSM.
EMS	5–18. The lower the score the more severe the deficits. Normal function: 17+, grade 1: 13–16, grade 2: 9–12, grade 3: 5–8. Upper extremity 27.8%, lower extremity 22.2%, coordination 16.7%, paraesthesia/pain 16.0%, bladder and bowel function 16.7%	No	Affected by dysdiadochokinesia (++) and paresis of the upper extremity and vegetative symptoms (+)		Good at assessing clinical state and grade of severity of CSM. Better sensitivity to reveal functional deficit (by assessing proprioception/coordination).
Prolo scale	2–10. The lower the score the more severe the deficits. Normal function: 9+, grade 1: 7 + 8, grade 2: 5 + 6, grade 3: 2–4. Economic status 50%; functional status 50%.	No	Mildly affected by vegetative symptoms (+)	Does not reflect clinical symptoms significantly -Not good for pre-op assessing the grade of severity	Good correlation between high pre-op scores and better outcomes. Good for assessing normalisation¨ and rehabilitation (regained ability for work or for leisure time).

mJOA: modified Japanese Orthopaedic Association; CMS: Cervical Myelopathy Scale; EMS: European Myelopathy Scale.