====== Meyerding classification ======
A commonly adopted method of grading [[spondylolisthesis]] is the Meyerding classification, based on the ratio of overhanging part of the superior [[vertebral body]]] to anteroposterior length of the adjacent inferior vertebral body: 

It divides the superior [[endplate]] of the vertebra below into 4 quarters. The grade depends on the location of the posteroinferior corner of the vertebra above. 

{{::meyerding.jpg|}}

grade I: 0-25%
    
grade II: 26-50% 
    
grade III: 51-75% 
    
grade IV: 76-100%  
    
grade V ([[spondyloptosis]]): >100%
((Meyerding HW. Spondylolisthesis. Surg Gynecol Obstet 1932;54:371–7))
((Rothman RH, Simeone FA. The Spine. Philadelphia
1982))
----
The original Meyerding [[classification]] grading of [[spondylolisthesis]] of the cranial vertebra in relation to the lower vertebra does not seem to be valid for [[isthmic spondylolisthesis]] on MRI, since hypoplasia or shortening of the cranial, spondylolytic vertebra is not taken into account. Describing a finding as spondylolisthesis rather than [[spondylolysis]] is not only a question of taxology, but implies a more serious state of the disease. Therefore, the term “spondylolisthesis” should be reserved for patients with a real slip and not a slip mimicked by a shortened, hypoplastic vertebra
((Niggemann P, Kuchta J, Grosskurth D, Beyer HK, Hoeffer J, Delank KS.
Spondylolysis and isthmic spondylolisthesis: impact of vertebral hypoplasia on
the use of the Meyerding classification. Br J Radiol. 2012 Apr;85(1012):358-62.
doi: 10.1259/bjr/60355971. Epub 2011 Jul 12. PubMed PMID: 21750127; PubMed
Central PMCID: PMC3486675.
)).