Lumbar spinal stenosis: a review of biomechanical studies.

OBJECTIVE

To investigate the biomechanical aspects of etiology, pathology, clinical manifestation, diagnosis and surgical treatment of the lumbar spinal stenosis.

METHODS

A series of biomechanical methods, such as three-dimensional finite element models, three-dimensional kinematic measurement, cadeveric evaluation, and imaging assessment was applied to correlate lumbar biomechanics and lumbar spinal stenosis. Surgery of lumbar spinal stenosis has been improved.

RESULTS

The stresses significantly concentrate on the posterolateral part of the annulus fibrosus of disc, the posterior surface of vertebral body, the pedicle, the interarticularis and the facet joints. This trend is intensified by disc degeneration and lumbar backward extension. Posterior element resection has a definite effect upon the biomechanical behavior of lumbar vertebrae. The improved operations proved satisfactory.

CONCLUSION

Stress concentration in the lumbar vertebrae is of importance to the etiology of degenerative lumbar spinal stenosis, and disc degeneration is the initial key of this process. Then these will be aggravated by backward extension. Functional radiography and myelography are of assistance to the diagnosis of the lumbar spinal stenosis. For the surgical treatment of the lumbar spinal stenosis, destruction of the posterior element should be avoid as far as possible based upon the thorough decompression. Maintaining the lumbar spine in flexion by fusion after decompression has been proved a useful method. When developmental spinal stenosis is combined with disc herniation, discectomy through laminotomy is recommend for decompression.