Intradiscal pressure in the degenerated porcine intervertebral disc

S. Holm; L. Ekström; A. Kaigle Holm; T. Hansson

doi:10.1055/s-0037-1616584

Veterinary and Comparative Orthopaedics and Traumatology, Table of Contents

Vet Comp Orthop Traumatol 2007; 20(01): 29-33
DOI: 10.1055/s-0037-1616584

Original Research

Schattauer GmbH

Intradiscal pressure in the degenerated porcine intervertebral disc

S. Holm

¹Department of Orthopaedics, Sahlgrenska University Hospital, Göteborg, Sweden

,

L. Ekström

¹Department of Orthopaedics, Sahlgrenska University Hospital, Göteborg, Sweden

,

A. Kaigle Holm

¹Department of Orthopaedics, Sahlgrenska University Hospital, Göteborg, Sweden

,

T. Hansson

¹Department of Orthopaedics, Sahlgrenska University Hospital, Göteborg, Sweden

› Author Affiliations

Abstract

Summary

Measuring intradiscal pressure is one way of mechanically assessing the discs degenerative state. In this study, the load-bearing capacity of degenerated and their adjacent lumbar intervertebral discs was evaluated using two different injury models. Seventeen adolescent pigs were divided into two groups, an annulus injury group and an endplate injury group. The annulus injury group was subjected to a stab incision in the L3-L4 disc, whereas the endplate injury group received a cranial endplate perforation of the L4 vertebral body. Both groups were biomechanically evaluated three months later using a miniaturized servohydraulic testing machine across L2-L4 and with two pressure needles inserted into the nucleus pulposus of the L2-L3 and L3-L4 discs. Linear relationships between the intradiscal pressure and the applied load were determined within the load range studied. When comparing the ratio of the injured to the adjacent disc pressure, the endplate injury was lower (mean value 0.31) than the annulus injury (mean value 0.51). The pressures in the discs adjacent to the degenerated level were found to be slightly higher. This increase can be expected due to a redistribution in mobility demands in segments adjacent to those with increased stiffness, i.e. degenerated intervertebral discs.

Keywords

Degeneration - injury model - intradiscal pressure - porcine lumbar spine

Full Text

References

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