Table 2.

Comparisons of clinical data and radiographic parameters in the two groups

	Group E (n = 24)	Group D (n = 33)	P value
Fusion segments	2.3 ± 0.7	3.1 ± 1.2	0.005
Operation time (min)	185.7 ± 23.3	211.4 ± 35.8	0.003
Blood loss (ml)	198.8 ± 49.5	242.5 ± 61.2	0.006
Pedicle size (mm)	4.4 ± 0.6	4.7 ± 0.5	0.045
Main curve
Pre-operation (°)	33.5 ± 15.3	41.7 ± 18.5	0.082
Immediately post-op (°)	5.5 ± 2.7	6.9 ± 4.8	0.204
Correction (%)	83.3 ± 21.6	81.2 ± 20.1	0.707
Last follow-up (°)	10.3 ± 3.0	11.5 ± 3.3	0.165
Correction loss (%)	16.3 ± 8.9	8.8 ± 6.4	0.001
Compensatory curve
Pre-operation (°)	23.5 ± 15.3	27.8 ± 16.4	0.319
Immediately post-op (°)	12.5 ± 6.9	15.3 ± 7.4	0.153
Last follow-up (°)	14.5 ± 7.6	17.7 ± 7.9	0.131
CBD
Pre-operation (cm)	1.3 ± 1.6	1.5 ± 1.3	0.605
Immediately post-op (cm)	0.2 ± 0.9	0.2 ± 0.8	0.813
Last follow-up (cm)	0.2 ± 1.0	0.1 ± 0.8	0.677
Segmental kyphosis
Pre-operation (°)	17.4 ± 14.7	24.2 ± 18.5	0.142
Immediately post-op (°)	6.3 ± 3.0	6.9 ± 3.8	0.524
Correction (%)	65.1 ± 23.8	71.7 ± 24.9	0.319
Last follow-up (°)	10.2 ± 3.0	8.2 ± 3.3	0.023
Correction loss (°)	24.5 ± 13.7	5.1 ± 4.1	0.000
TK
Pre-operation (°)	27.8 ± 15.8	28.5 ± 17.1	0.875
Immediately post-op (°)	25.0 ± 7.7	24.8 ± 8.2	0.926
Last follow-up (°)	26.8 ± 8.4	25.9 ± 8.8	0.699
LL
Pre-operation (°)	− 38.5 ± 16.3	− 37.2 ± 18.4	0.784
Immediately post-op (°)	− 37.9 ± 17.4	− 38.8 ± 18.8	0.855
Last follow-up (°)	− 39.7 ± 21.2	− 40.3 ± 20.8	0.915
SVA
Pre-operation (cm)	1.1 ± 1.7	1.0 ± 1.5	0.815
Immediately post-op (cm)	0.7 ± 1.5	0.7 ± 1.6	0.727
Last follow-up (cm)	0.7 ± 1.6	0.6 ± 1.5	0.810

CBD: Coronal balance distance; TK: thoracic kyphosis; LL: lumbar lordosis; SVA: sagittal vertical axis