In this first part of a three-part report, the mechanical behavior of 42 fresh human cadaver lumbar motion segments in flexion, extension, lateral bending, and torsion is examined. Motions and intradiskal pressure changes that occurred in response to these loads, with posterior elements both intact and excised, are reported.

In this second part of a three-part report, we consider the mechanical behavior of 42 fresh human cadaver lumbar motion segments in compression, and in anterior, posterior, and lateral shear. We report the motions and the intradiskal pressure increases that occurred with posterior elements both intact and destroyed. We also examine to what extent intervertebral disk gross morphology can explain the large scatter in the results presented here, as well as in the results reported in Part I concerning mechanical behavior in flexion, extension, lateral bending, and torsion.

No abstract