Table 2.

Characteristics of studies evaluating miss diagnosis of tandem cervical and thoracic stenosis

Study	Study period	Study design	Level of evidence	Study population	Total study N	Miss diagnosis N	Stenosis pattern of miss diagnosis	Outcome of study
Sun el at.	1994-2001	Case control	III	CSM+T OLF	35	6	T OLF	75% of those who meet the upper limb function score composition ratio > 36% and bladder function score ≤ 2 points are thoracic OLF combined with CSM
Zhou el at.	1987-1993	Retrospective Case Series	IV	C OPLL	318	14a	T OLF	There is a high possibility of cervical OPLL combined with thoracic OLF when it shows continuous cervical OPLL, mixed cervical OPLL and DISH disease involving multiple segments.
Sun el at.	1991-2003	Retrospective Case Series	IV	T OLF +CSM	40	7	T OLF	When cervical MRI finds OLF in the upper thoracic spine, MRI examination of the entire thoracic spine should be performed to determine whether OLF occurs in the thoracolumbar and middle and lower thoracic spine.
Jannelli el at.	2015-2018	Retrospective Case Series	IV	TSS	8	2	Dorsal myelopathy	Electrophysiological techniques can be considered an objective and cost-effective tool in the assessment of TSS and can improve surgical decision-making.
Total					401	29

CSM cervical spondylotic myelopathy, OLF ossification of ligamentum flavum, OPLL ossification of posterior longitudinal ligament, DISH diffuse idiopathic skeletal hyperostosis TSS tandem spinal stenosis