Degenerative Spondylolisthesis¶

Definition¶

Degenerative spondylolisthesis is the translation of a vertebra on the one below due to degeneration of the disc and facet joints, with intact pars interarticularis. It is the most common type of spondylolisthesis in adults over 50 and is most frequent at L4–L5.

Risk Factors¶

• Age >50
• Female sex (6:1 female predominance)
• L4–L5 — the sagittal facet orientation at this level provides less resistance to anterior translation compared to the more coronal facets at L5–S1
• Diabetes, obesity, and generalized ligamentous laxity
• Sacralization of L5 (shifts biomechanical stress to L4–L5)

Imaging Findings¶

Key Feature: Intact Pars¶

• The pars interarticularis is intact — this distinguishes degenerative from isthmic spondylolisthesis
• CT sagittal images through the pars confirm continuity of the posterior arch

Radiography/CT¶

• Anterior slip of L4 on L5 (most common); usually Grade I (<25%)
• Degenerative changes: disc narrowing, facet arthropathy, osteophytes
• Flexion-extension views may show dynamic instability (slip increases in flexion)

MRI¶

• Sagittal T2: anterior translation with stenosis at the slip level; facet effusion
• Axial T2: characteristic findings at the level of the slip:
  • Central canal stenosis from the slip
  • Redundant nerve roots below the level of stenosis
  • Facet effusion and synovial cysts (commonly associated)

Key Points¶

• Degenerative spondylolisthesis has an intact pars — caused by facet and disc degeneration
• Most common at L4–L5 in women over 50
• Usually low-grade (Grade I) but can cause significant stenosis
• Associated with facet synovial cysts at the same level
• CT confirms intact pars; MRI evaluates stenosis and neural compression
• Treatment ranges from conservative to decompression with fusion depending on severity and instability

References¶

1. Koslosky E, Gendelberg D. Classification in Brief: The Meyerding Classification System of Spondylolisthesis. Clin Orthop Relat Res. 2020. https://pmc.ncbi.nlm.nih.gov/articles/PMC7170696/
2. Margetis K, Gillis CC. Spondylolisthesis. StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK430767/
3. Wang YXJ, Káplár Z, Deng M, Leung JCS. Lumbar degenerative spondylolisthesis epidemiology: A systematic review with a focus on gender-specific and age-specific prevalence. J Orthop Translat. 2016;11:39-52. https://pmc.ncbi.nlm.nih.gov/articles/PMC5866399/
4. Chaput C, Padon D, Rush J, Lenehan E, Rahm M. The significance of increased fluid signal on magnetic resonance imaging in lumbar facets in relationship to degenerative spondylolisthesis. Spine (Phila Pa 1976). 2007;32(17):1883-7. https://pubmed.ncbi.nlm.nih.gov/17762297/
5. Anderson DG, Limthongkul W, Sayadipour A, et al. A radiographic analysis of degenerative spondylolisthesis at the L4-5 level. J Neurosurg Spine. 2012;16(2):130-4. https://pubmed.ncbi.nlm.nih.gov/22117143/
6. Kalichman L, Hunter DJ. Diagnosis and conservative management of degenerative lumbar spondylolisthesis. Eur Spine J. 2008;17(3):327-335. https://pmc.ncbi.nlm.nih.gov/articles/PMC2270383/
7. Meyerding classification of spondylolisthesis. Radiopaedia.org. https://radiopaedia.org/articles/meyerding-classification-of-spondylolisthesis

Related Articles¶

• Spondylolisthesis
• Isthmic Spondylolisthesis
• Facet Arthropathy
• Facet Synovial Cyst
• Lumbar Spinal Stenosis