Biomechanical Characterization of Unilateral and Bilateral Posterior Lumbar Interbody Fusion Constructs

Table 4

AT-loading descriptive statistics.

Stage	Flexibility parameters	Raw				Normalized
		Mean	Std. deviation	95% LCL	95% UCL	Mean	Std. deviation	95% LCL	95% UCL
Intact	ROM	3.63	0.42	2.70	4.55	1.00		—	—
	NZ	0.86	0.17	0.48	1.23	1.00
Facetectomy	ROM	4.53	0.51	3.40	5.66	1.26	0.14	0.95	1.58
	NZ	1.05	0.20	0.61	1.49	1.49	0.28	0.86	2.11
Unilateral	ROM	2.67	0.36	1.86	3.47	0.74	0.10	0.52	0.97
	NZ	0.63	0.14	0.32	0.93	0.89	0.20	0.46	1.33
Bilateral	ROM	1.48	0.16	1.12	1.83	0.41	0.04	0.31	0.51
	NZ	0.26	0.05	0.15	0.36	0.36	0.07	0.21	0.52
Unilateral+cage	ROM	2.46	0.27	1.86	3.07	0.69	0.08	0.52	0.85
	NZ	0.66	0.09	0.45	0.86	0.69	0.08	0.52	0.85
Bilateral+cage	ROM	1.64	0.19	1.22	2.07	0.46	0.05	0.34	0.58
	NZ	0.38	0.06	0.25	0.51	0.55	0.08	0.36	0.73

AT: results of axial-torsion testing. Raw values indicate motion measured in degrees while normalized values represent the amount of motion as a percentage of intact values.