Lumbar Spondylosis and Spondylolisthesis

Spondylolisthesis is a slippage on one vertebra on another. The term derives from greek spondylos  (vertebra) and olisthesis (slip or slide down). The most commonly affected level is L4/5 . A variety of factors contribute to the development of spondylolisthesis and these form the basis of the most commonly used classification system, by Wiltse, Macnab and Newman:

1. Congenital or Dysplastic: congenital hypoplasia of the posterior elements facet joints and laminae especially at L5/S1 and associated therefore with spina bifida occulta.

2. Isthmic: problems associated with the pars interarticularis, this is further subdivided into 2A (chronic breakage of pars), 2B (elongated pars –representing repeated injury and fracture healing) and 2C (acute pars fracture).

3. Degenerative: due to disc degeneration and subsequent development of instability, subsequent facet overloading and facet degeneration. The role of the lumbosacral or slip angle or how tilted the vertebra with respect to the horizontal is also postulated to play a major role.

4. Traumatic: due to an acute fracture not involving the pars interarticularis, an example is fracture through the pedicles

5. Pathologic: due to turmour metastasis or infection or other bone diseases

6. Iatrogenic or Postsurgical: after decompression surgery with partial or complete loss of posterior elements typically after overzealous resection of the pars interarticularis or facet joints.


Case Illustration - Type 2A– Isthmic Spondylolisthesis - Chronic Pars Defect

CT Facet Joint Degeneration with bone cyst formation

Text Box: Procedure
MEDRx Decompression
Minimal Invasive SEXTANT TLIF (Transforaminal Lumbar Interbody Fusion) with olisthesis reduction

Return to Lumbar Spine Problems

Click to continue

Female late Forties

Complaining of bilateral back and buttock pain with leg pain the right side is worse than left

The symptoms are getting progressively worse over the past 6 months




OLISTHESIS Reduction using SEXTANT Instrumentation

Severe Lumbar L3-4 Foraminal Stenosis  - Right side more severe than Left

Degenerative Spondylolisthesis

Sextant TLIF Click to continue



Copyright © 2008 Spine Care Hong Kong