In Vitro Comparison of Dynesys, PEEK, and Titanium Constructs in the Lumbar Spine
Table 1
L4-L5 kinematic results (mean ± SD).
Intact
DYN
PEEK
TI
Destabilized
ROM (°)
FE
12.47 ± 3.77
5.39 ± 2.50
4.83 ± 1.99
4.43 ± 1.78
14.45 ± 3.57
LB
9.68 ± 2.40
5.05 ± 2.34
4.55 ± 1.60
3.33 ± 1.37
9.86 ± 3.14
AT
4.45 ± 3.16
4.68 ± 3.12
3.55 ± 2.40
3.24 ± 1.97
4.65 ± 1.68
AC
0.28 ± 0.16
0.23 ± 0.13
0.28 ± 0.13
0.34 ± 0.25
0.46 ± 0.28
IPT (mm)
Left
FE
7.61 ± 1.49
4.78 ± 1.61
5.50 ± 1.89
5.32 ± 1.78
9.02 ± 2.31
LB
9.51 ± 2.63
8.64 ± 2.32
8.92 ± 2.71
8.38 ± 2.50
9.22 ± 2.00
AT
5.18 ± 2.99
5.26 ± 3.05
4.98 ± 2.71
4.64 ± 2.21
4.81 ± 1.49
AC
1.04 ± 0.51
0.86 ± 0.56
0.92 ± 0.54
0.95 ± 0.70
1.47 ± 0.55
Right
FE
8.55 ± 2.47
5.85 ± 2.46
6.22 ± 2.41
6.06 ± 2.34
9.78 ± 2.86
LB
8.85 ± 1.76
8.36 ± 1.96
7.99 ± 1.89
7.69 ± 1.80
9.38 ± 1.47
AT
3.68 ± 1.65
4.09 ± 1.87
3.57 ± 1.62
3.44 ± 1.53
3.87 ± 1.19
AC
1.11 ± 0.39
0.88 ± 0.55
0.94 ± 0.49
1.00 ± 0.65
1.69 ± 0.77
ID (mm)
Left
FE
6.87 ± 1.90
2.15 ± 1.25
2.74 ± 1.38
2.44 ± 1.15
8.22 ± 2.59
LB
5.97 ± 2.06
3.26 ± 1.97
3.69 ± 1.61
2.79 ± 1.32
5.51 ± 1.97
AT
0.80 ± 0.64
0.42 ± 0.34
0.47 ± 0.45
0.39 ± 0.23
0.98 ± 0.73
AC
0.79 ± 0.36
0.10 ± 0.09
0.16 ± 0.09
0.10 ± 0.08
1.28 ± 0.62
Right
FE
7.47 ± 2.29
2.26 ± 1.97
2.40 ± 0.84
2.17 ± 0.84
9.04 ± 2.96
LB
5.26 ± 1.32
2.65 ± 1.75
2.36 ± 0.83
1.52 ± 0.57
5.87 ± 2.06
AT
0.68 ± 0.49
0.55 ± 0.45
0.68 ± 0.84
0.60 ± 0.67
1.08 ± 0.60
AC
0.90 ± 0.35
0.13 ± 0.10
0.17 ± 0.11
0.10 ± 0.04
1.52 ± 0.85
ROM = range of motion; IPT = interpedicular travel; ID = interpedicular displacement; FE = flexion-extension; LB = lateral bending; AT = axial torsion; AC = axial compression; DYN = Dynesys; TI = Titanium rod.
