TABLE 4.

Comparison of Those Considered Successful and Unsuccessful

		Success (n = 80)	Failure (n = 32)	P
Preoperative
Age at surgery		12.7 ± 1.5 (8.2 to 16.7)	12.5 ± 1.0 (10.2 to 14.7)	0.54
Sex (% Female)		94%	91%	0.56
Females premenachal (%)		77%	82%	0.52
Mass		45.2 ± 11.1 (24.5 to 81.1)	44.8 ± 11.6 (30.8 to 78.0)	0.32
BMI		18.9 ± 3.7 (12.9 to 31.7)	18.9 ± 3.5 (14.1 to 27.7)	0.92
Risser	Mean	0.6 ± 0.9 (0 to 3)	0.4 ± 0.8 (0 to 3)	0.29
Risser: number of cases	0	53	25	0.66
	1	13	3
	2	10	3
	3	4	1
Sanders score (n = 33)		3.5 ± 1.3 (2 to 6)	2.8 ± 0.8 (2 to 4)	0.69
Major coronal Cobb		48.3° ± 8.9 (31 to 70)	56.5° ± 11.1 (35 to 81)	<0.001
Major Cobb group (% success for group)	30–39°	10 (83%)	2	0.03
	40–49°	36 (78%)	10
	50–59°	25 (73%)	9
	>60°	9 (45%)	11
Flexibility		42.3% ± 19.2 (0 to 100)	34.6% ± 20.9 (2 to 91)	0.046
Intraoperative
Tether location
Thoracic		74	30	N/A ψ
Lumbar		3	1
Dual		3	1
Postoperative
Tether breakage		19/80 (24%)	17/32 (53%)	0.003
Follow up, mo		35.6 ± 8.7 (24 to 61)	41.7 ± 10.9 (15 to 64)	0.001

ψ Small group numbers preclude meaningful statistical analysis.