TABLE 4.
Maximum Tensile (Tension and Compression) and Shear Deformations (Average ± SD) of the Discs in the Patients with DDD and in the Normal Subjects During End Ranges of Motion of the Torso.
Left Torsion | Right Torsion | Left Bend | Right Bend | Extension | Flexion | ||
---|---|---|---|---|---|---|---|
L2–L3 | |||||||
Tension | DDD | 29% ± 20%* | 38% ± 33%* | 25% ± 22% | 18% ± 19% | 32% ± 21%* | 45% ± 11%* |
Normal | 10% ± 8%* | 11% ± 9%* | 12% ± 9% | 18% ± 6% | 12% ± 11%* | 26% ± 9%* | |
Compression | DDD | −7% ± 24% | −14% ± 20% | −41% ± 32%* | −22% ± 22% | −20% ± 13% | −18% ± 13% |
Normal | −12% ± 11% | −9% ± 6% | −13% ± 16%* | −14% ± 10% | −13% ± 14% | −17% ± 8% | |
Shear | DDD | 53% ± 27% | 53% ± 24%* | 65% ± 32%* | 56% ± 23%* | 55% ± 34% | 66% ± 30%* |
Normal | 34% ± 17% | 20% ± 12%* | 15% ± 8%* | 23% ± 11%* | 31% ± 19% | 18% ± 16%* | |
L3–L4 | |||||||
Tension | DDD | 26% ± 26% | 26% ± 19%* | 24% ± 24% | 35% ± 25%* | 23% ± 20% | 47% ± 25%* |
Normal | 18% ± 16% | 10% ± 8%* | 15% ± 9% | 12% ± 10%* | 16% ± 13% | 22% ± 13%* | |
Compression | DDD | −11% ± 10% | −17% ± 21% | −31% ± 17%* | −24% ± 20% | −24% ± 20% | −28% ± 21% |
Normal | −13% ± 9% | −10% ± 7% | −13% ± 10%* | −12% ± 7% | −14% ± 9% | −15% ± 10% | |
Shear | DDD | 62% ± 23%* | 50% ± 31% | 63% ± 26%* | 64% ± 27%* | 62% ± 28%* | 54% ± 32% |
Normal | 26% ± 17%* | 29% ± 21% | 21% ± 14%* | 28% ± 18%* | 26% ± 10%* | 29% ± 17% |
Using Mixed Model Analysis of Variance, Statistically Significant Differences Between DDD and Normal Subjects were Marked as *, P < 0.05. No Statistically Significant Difference was Found Between L2–L3 and L3–L4 Discs in All Cases