The shortcomings of the classification systems of McLain and Weinstein 1) and Enneking 2) , were partly addressed by Boriani et al. who developed a new staging system for primary vertebral tumor 3).
Enneking classification in treatment of spine tumors has been found to be insufficient for surgical planning over time. Because of that, in 1997, Boriani et al have published a study about the new terminology and surgical staging for primary spine tumors. The authors stated a new classification system known as Weinstein Boriani Biagini classification, which is still actively in use today 4).
https://openi.nlm.nih.gov/detailedresult.php?img=PMC4472586_asj-9-386-g001&req=4
The WBB surgical staging system describes the involvement of a specific vertebra in terms of sectors involved, arranged clockwise in 12 sectors on an axial vertebral face. The lesion is further confined to five layers of tissue penetration denoted as A-E
A— Extra-osseous soft tissue
B — Intrauosseous superficial
C — Intraosseous deep
D — Extraosseous (extradural)
E — Extraosseous (intradural)
Results indicate moderate interobserver reliability and substantial and near-perfect intraobserver reliability for both the Enneking and WBB classification in terms of staging and guidance for treatment, despite a less than moderate interobserver reliability in interpreting the Enneking local tumor extension and WBB sector. Before incorporating the classifications in the clinical practice and research studies, further work is required to investigate the validity of the classifications 5).
http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S1681-150X2011000300003