Table 2.

Breakdown According to Each SINS Criterion

Factor	Fracture (n = 57) Vertebral Segments	No Fracture (n = 353) Vertebral Segments	Fractures
			No.	Total No.	%
Location
Junctional (occiput-C2, C7-T2, T11-L1, L5-S1)	25	139	25	164	15.24
Mobile spine (C3-C6, L2-L4)	20	91	20	111	18.02
Semirigid (T3-T10)	12	108	12	120	10
Rigid (S2-S5)	0	15	0	15	0
Pain
Mechanical	23	92	23	115	20
Occasional and nonmechanical	18	157	18	175	10.29
Pain free	16	104	16	120	13.33
Bone lesion type
Lytic	48	208	48	256	18.75
Mixed	6	83	6	89	6.74
Blastic	3	62	3	65	4.62
Alignment
Subluxation/translation	1	0	1	1	100
Kyphosis/scoliosis	9	22	9	31	29.03
Normal	47	331	47	378	12.43
Vertebral body collapse
≥ 50%	3	9	3	12	25
< 50%	27	44	27	71	38.03
No collapse but > 50% body involved by tumor	13	65	13	78	16.67
None of the above	14	235	14	249	5.62
Posterior element involvement
Bilateral	7	59	7	66	10.61
Unilateral	32	152	32	184	17.39
Not involved	18	142	18	160	11.25
SINS classification
Stable	13	185	13	198	6.57
Indeterminant	42	167	42	209	20.1
Unstable	2	1	2	3	66.67

Abbreviation: SINS, Spinal Instability Neoplastic Scoring system.