Lumbosacral transitional vertebrae: classification, imaging findings, and clinical relevance

Area of Science:

• Radiology
• Orthopedics
• Anatomy

Background:

• Lumbarization-sacralization variants (LSTVs) are common congenital anomalies of the lumbosacral spine.
• Their association with low back pain remains a subject of debate in medical literature.
• LSTVs encompass sacralization of the fifth lumbar vertebra and lumbarization of the first sacral segment.

Purpose of the Study:

• To review the diagnostic criteria for LSTVs.
• To discuss the potential etiologies of low back pain associated with LSTVs.
• To emphasize the clinical significance of identifying LSTVs in surgical and interventional procedures.

Main Methods:

• Review of existing literature on LSTVs and low back pain.
• Analysis of imaging findings related to LSTVs.
• Discussion of anatomical variations and their clinical implications.

Main Results:

• LSTVs present with diverse morphologies, including broadened transverse processes or complete vertebral fusion.
• Pain may originate from the level above the transition, contralateral facet joint, or anomalous articulation.
• Accurate identification and numbering of LSTVs are critical for procedural safety.

Conclusions:

• LSTVs are frequently encountered spinal variations with debated links to low back pain.
• Understanding LSTV morphology and potential pain generators is essential for patient management.
• Correctly identifying LSTVs prevents surgical or interventional errors at incorrect spinal levels.