Increase in facet joint loading after nucleotomy in the human lumbar spine

Low-back pain has been related to degenerative changes after nucleotomy. Although several etiologies for pain after nucleotomy have been proposed, there is evidence of pain arising in the facet joints in general, which may be related to changes in load transfer. This study addresses the effect of nucleotomy on facet joint loading.Nine human lumbar motion segments (age: 40-59 years) were loaded in axial compression and extension-flexion. Reaction forces were compared with soft tissue structures sequentially removed. After nucleotomy the facets supported significantly greater load, almost doubling from a median of 8.6% of the applied external force to 15.8%. Force transmission related to the capsular ligament increased significantly from an intact median of 1.2-5.1% after nucleotomy. No correlation was observed between force increase on the facets and the proportion of disc nucleus removed.Even a small quantity of nucleus removal (range: 0.7-1.7. g) increased the forces transmitted over the facet joints, both with and without capsular ligaments. This suggests that the proportion of material removed might not be important clinically with regard to facet joint degeneration and pain. © 2014 Elsevier Ltd.

Schlagworte

Capsular ligament

Facet joint

In vitro

Load-sharing

Lumbar spine

Nucleotomy

DDC Class

610: Medicine, Health

620: Engineering

Options

Increase in facet joint loading after nucleotomy in the human lumbar spine