Table 7.

Summary of disc height measurements at implanted, upper and lower levels

	Single level ACDF	Single level Bryan	Double level ACDF	Double level Bryan
Implanted level (mm)
AIH
Pre-op	4.35 ± 1.08	3.67 ± 1.27	4.35 ± 1.03	3.45 ± 0.79
Post-op	8.98 ± 1.27	2.73 ± 1.15	8.23 ± 1.76	2.98 ± 1.19
F/U	7.70 ± 1.37	2.39 ± 0.35	6.76 ± 1.84	2.63 ± 0.69
p value	<0.0001		<0.0001
PIH
Pre-op	2.81 ± 0.91	2.84 ± 0.99	3.74 ± 0.75	2.85 ± 0.57
Post-op	4.81 ± 1.40	3.37 ± 1.02	6.25 ± 1.18	3.29 ± 0.86
F/U	3.70 ± 1.0	3.26 ± 0.88	4.8 ± 1.05	3.05 ± 0.85
p value	0.0052		<0.0001
Upper level (mm)
AIH
Pre-op	4.27 ± 0.80	4.5 ± 1.02	5.00 ± 1.27	4.20 ± 1.03
Post-op	4.24 ± 0.71	4.33 ± 0.82	4.72 ± 1.12	4.12 ± 0.70
F/U	3.92 ± 0.66	4.23 ± 0.89	4.33 ± 1.03	4.27 ± 0.76
p value	0.1264		0.0172
PIH
Pre-op	2.99 ± 0.66	4.12 ± 0.89	4.11 ± 0.95	3.53 ± 0.90
Post-op	3.46 ± 0.66	4.20 ± 1.04	3.80 ± 0.86	3.52 ± 0.87
F/U	2.95 ± 0.61	3.74 ± 0.82	3.35 ± 0.75	3.48 ± 0.95
p value	<0.0001		0.8363
Lower level (mm)
AIH
Pre-op	4.84 ± 1.23	4.77 ± 0.91	4.68 ± 1.41	4.03 ± 1.15
Post-op	4.90 ± 1.29	4.86 ± 1.04	4.41 ± 1.17	3.96 ± 0.84
F/U	4.40 ± 1.14	4.57 ± 1.04	4.00 ± 1.23	4.01 ± 1.05
p value	0.7598		<0.0001
PIH
Pre-op	2.95 ± 0.52	4.24 ± 0.87	4.27 ± 0.94	4.07 ± 0.57
Postop	3.35 ± 0.74	4.12 ± 0.80	3.79 ± 0.74	3.78 ± 0.40
F/U	2.98 ± 0.56	4.59 ± 1.88	3.38 ± 0.98	3.31 ± 0.46
p value	<0.0001		<0.0001

p = 0.05 set value for statistical significance using the mixed model