Surgical treatment of Lenke 5 adolescent idiopathic scoliosis: Comparison of anterior vs posterior approach

Table 1 Pre-operative radiographic and self-reported data for anterior and posterior thoraco-lumbar approaches for all cases, selective fusion, and selective fusions where distal level of fixation was the third lumbar vertebra for Lenke 5 curves

	All cases			Selective fusions only			Selective fusions where dLOF = L3
	Mean (SD)			Mean (SD)			Mean (SD)
	Ant (n = 40)	Post (n = 40)	P-value	Ant (n = 39)	Post (n = 20)	P-value	Ant (n = 25)	Post (n = 14)	P-value
Thoracic Cobb	28.7 (7.2)	29.2 (8.0)	0.759	28.3 (6.7)	26.8 (5.7)	0.395	27.6 (5.9)	25.6 (5.5)	0.313
Lumbar Cobb	46.9 (6.7)	47.1 (6.6)	0.880	46.8 (6.7)	48.0 (6.8)	0.0527	47.5 (7.1)	46.6 (6.8)	0.687
LSTOA	15.8 (4.7)	17.0 (5.7)	0.342	15.7 (4.8)	18.3 (6.3)	0.086	15.8 (4.8)	16.3 (4.8)	0.762
Thoracolumbar apical translation (centimeters)	5.0 (1.6)	5.4 (1.5)	0.241	5.0 (1.6)	5.6 (1.7)	0.214	5.2 (1.7)	5.5 (1.3)	0.521
Disc angulation below dLOF (degrees)	0.7 (6.2)	1.9 (5.4)	0.351	0.8 (6.2)	2.3 (5.4)	0.372	2.8 (6.3)	0.4 (4.5)	0.220
Proximal junctional kyphosis (degrees)	4.1 (5.7)	4.7 (4.6)	0.607	4.0 (5.8)	3.2 (2.6)	0.522	4.2 (6.4)	3.2 (2.7)	0.573
Kyphosis from T5-T12 (degrees)	25.7 (10.4)	24.8 (10.0)	0.719	25.7 (10.5)	24.9 (10.2)	0.756	24.4 (10.9)	25.6 (11.1)	0.743
Kyphosis from T10-L2 (degrees)	5.6 (11.3)	3.8 (8.7)	0.437	6.1 (11.0)	7.5 (7.5)	0.622	8.0 (11.7)	5.9 (7.2)	0.547
Lordosis from T12-top of Sacrum (degrees)	60.0 (12.2)	57.4 (10.8)	0.324	60.1 (12.3)	55.7 (11.5)	0.196	57.8 (12.9)	58.9 (8.0)	0.791
SRS (total)	3.9 (0.5)	4.0 (0.3)	0.463	3.9 (0.5)	4.1 (0.3)	0.371	3.9 (0.4)	4.1 (0.3)	0.305
SRS (self)	3.8 (0.7)	3.7 (0.6)	0.367	3.8 (0.7)	3.5 (0.6)	0.335	3.8 (0.5)	3.5 (0.6)	0.282
SRS (pain)	3.7 (0.7)	3.9 (0.6)	0.269	3.6 (0.7)	4.0 (0.4)	0.139	3.6 (0.6)	4.0 (0.4)	0.087
SRS (function)	4.0 (0.6)	4.1 (0.4)	0.469	4.1 (0.6)	4.2 (0.5)	0.392	4.2 (0.4)	4.2 (0.5)	0.691
SRS (activity)	4.5 (0.7)	4.6 (0.5)	0.576	4.5 (0.7)	4.6 (0.6)	0.572	4.5 (0.5)	4.6 (0.6)	0.496

LSTOA: Lumbo-sacral take-off angle; dLOF: Distal level of fixation; T: Thoracic; L: Lumbar; SD: Standard deviation.

Table 2 Independent t-test statistical results for surgical outcomes associated with anterior vs posterior thoraco-lumbar approaches for all cases, selective fusions, and selective fusions where distal level of fixation was the third lumbar vertebra for Lenke 5 curves

	All cases			Selective fusions only			Selective fusions where dLOF = L3
	Mean (SD)			Mean (SD)			Mean (SD)
	Ant (n = 40)	Post (n = 40)	P-value	Ant (n = 39)	Post (n = 20)	P-value	Ant (n = 25)	Post (n = 14)	P-value
Thoracic Cobb percent correction	36.7 (23.2)	48.1 (24.3)	0.036	35.9 (22.9)	35 (20.2)	0.890	40.5 (24.6)	37.9 (17.7)	0.732
Lumbar Cobb percent correction	64.5 (14.7)	63.4 (17.0)	0.764	64.7 (14.9)	58.2 (17.1)	0.135	69.1 (12.6)	54.6 (16.4)	0.0041
LSTOA percent correction	46.6 (17.0)	44.9 (21.6)	0.688	46.9 (17.2)	46.2 (21.7)	0.900	48.8 (15.6)	37.7 (19.4)	0.058
Absolute change in thoracolumbar apical translation (centimeters)	3.6 (1.4)	3.2 (1.6)	0.293	3.6 (1.4)	3.5 (1.7)	0.669	3.9 (1.4)	3.2 (1.4)	0.157
Change in disc angulation below dLOF (degrees)	5.2 (9.5)	5.8 (5.0)	0.702	5.1 (9.6)	6.0 (5.7)	0.685	9.0 (7.9)	5.1 (5.7)	0.116
Change in proximal junctional Kyphosis (degrees)	3 (5.2)	4.4 (6.1)	0.253	2.7 (5.0)	2.7 (3.8)	0.989	2.7 (5.7)	3.1 (3.7)	0.806
Change in Kyphosis from T5-T12 (degrees)	-2.4 (9.7)	0.2 (10.3)	0.253	-2.3 (9.8)	-4.4 (8.4)	0.424	-3.5 (10.9)	-5.0 (8.2)	0.652
Change in Kyphosis from T10-L2 (degrees)	24.2 (158.1)	9.6 (8.2)	0.562	25.1 (160.1)	12.4 (8.0)	0.725	39.8 (199.7)	11.2 (8.0)	0.597
Change in Lordosis from T12-Top of sacrum (degrees)	25.0 (148.6)	-1.8 (11.6)	0.261	25.9 (150.5)	-6.0 (10.8)	0.350	39.1 (187.9)	-3.3 (11.0)	0.407
No. of fused vertebrae	4.9 (1.1)	9.0 (3.3)	< 0.0011	4.8 (1.0)	6.1 (1.0)	< 0.0011	5.1 (0.8)	5.8 (1.0)	0.025
Estimated blood loss (mL)	463 (327)	985 (1046)	0.0031	457 (329)	396 (166)	0.441	526 (381)	380 (168)	0.185
Length of hospitalization (d)	5.8 (1.5)	6.0 (1.4)	0.593	5.7 (1.4)	5.8 (1.0)	0.926	6.0 (1.2)	5.6 (1.2)	0.378

¹Denotes significant difference at P < 0.01. LSTOA: Lumbo-sacral take-off angle; dLOF: Distal level of fixation; T: Thoracic; L: Lumbar; SD: Standard deviation.

Table 3 Independent t-test statistical results for SRS outcomes associated with anterior vs posterior thoraco-lumbar approaches for all cases, selective fusions, and selective fusions where distal level of fixation was the third lumbar vertebra for Lenke 5 curves

	All cases			Selective fusions only			Selective fusions where dLOF = L3
	Mean (SD)			Mean (SD)			Mean (SD)
	Ant (n = 40)	Post (n = 40)	P-value	Ant (n = 39)	Post (n = 20)	P-value	Ant (n = 25)	Post (n = 14)	P-value
Change in SRS (total)	0.15 (0.54)	0.12 (0.53)	0.848	0.19 (0.52)	0.21 (0.31)	0.931	0.14 (0.44)	0.18 (0.32)	0.811
Change in SRS (self)	-0.54 (0.87)	-0.25 (0.93)	0.262	-0.47 (0.83)	-0.14 (0.81)	0.258	-0.40 (0.37)	-0.27 (0.84)	0.632
Change in SRS (pain)	0.49 (0.70)	0.45 (0.83)	0.860	0.55 (0.66)	0.38 (0.56)	0.456	0.48 (0.71)	0.25 (0.53)	0.399
Change in SRS (function)	0.12 (0.66)	-0.09 (0.65)	0.259	0.11 (0.67)	0.05 (0.37)	0.747	-0.03 (0.50)	0.06 (0.42)	0.653
Change in SRS (activity)	0.14 (0.50)	0.06 (0.58)	0.640	0.14 (0.51)	0.17 (0.61)	0.904	0.14 (0.56)	0.21 (0.64)	0.774

T: Thoracic; L: Lumbar; SD: Standard deviation; dLOF: Distal level of fixation.