Association of spinopelvic index with proximal junctional failure developing in adult spinal deformity after surgical treatment: an observational study

Table 1 Comparisons of data in patients with and without PJF

Variables	PJF group (n = 19)	PJF-free group (n = 80)	P Value
No. of females, n (%)	16 (84.2%)	63 (78.8%)	0.594
Age, years	66.05 ± 9.09	64.23 ± 8.19	0.394
BMI, kg/m²	25.58 ± 10.3	24.17 ± 10.59	0.431
Follow-up, months	51.2 ± 17.58	49.6 ± 19.38	0.72
UIV, n			0.087
T10 or above	16	51
L2-T11	3	29
LIV, n			0.744
S1, S2 or ilium, n	11	43
L4 or L5, n	8	37
FS	8.47 ± 1.93	8.21 ± 2.35	0.654
Preop-TK (°)	25.11 ± 14.05	15.23 ± 11.66	0.002^*
Preop- LL (°)	-22.68 ± 25.1	-22.89 ± 19.2	0.970
Preop-SS (°)	14.61 ± 13.53	23.7 ± 12.43	0.006^*
Preop-PT (°)	26.77 ± 13.1	23.39 ± 11.29	0.259
Preop-PI (°)	41.41 ± 10.88	47.21 ± 11.4	0.034^*
Preop-SVA (mm)	56.14 ± 68.87	49.96 ± 50.59	0.659
Postop-TK (°)	31.5 ± 10.24	20.34 ± 8.89	< 0.001^*
Postop-LL (°)	-37.95 ± 13.87	-38.43 ± 11.57	0.877
Postop-SS (°)	23.62 ± 10.76	30.83 ± 9.87	0.006^*
Postop-PT (°)	18.88 ± 11.37	16.07 ± 8.88	0.244
postop-SPI	1.62 ± 1.88	3.66 ± 2.87	0.015^*
Postop-SVA (mm)	13.52 ± 44.16	14.78 ± 32.07	0.886

Note: Mean values are presented as the mean ± SD; *, indicates P < 0.05; BMI body mass index, UIV Upper instrumented vertebra, LIV Lower instrumented vertebra, FS fusion segments; Preop- and postop-, pre-operative and post-operative; TK thoracic kyphosis, LL lumbar lordosis, SS sacral slope, PT pelvic tilt, PI pelvic incidence, SVA sagittal vertical axis, SPI spinopelvic index