Segmented lordotic angles to assess lumbosacral transitional vertebra on EOS

Area of Science:

• Radiology
• Orthopedic Surgery
• Anatomy

Background:

• Lumbosacral transitional vertebrae (LSTV) represent a common anatomical variation.
• Accurate identification and classification of LSTV are crucial for clinical assessment and surgical planning.
• Existing methods for LSTV assessment may have limitations in precision and classification.

Purpose of the Study:

• To evaluate the utility of vertical posterior vertebral angles (VPVA) measured on EOS imaging for identifying and classifying LSTV.
• To determine the diagnostic performance of VPVA in distinguishing different types of LSTV and related conditions.

Main Methods:

• EOS imaging data from 906 patients were retrospectively analyzed.
• Vertical posterior vertebral angles at the most caudal lumbar segment (cVPVA) and the segment above (pVPVA) were measured.
• Statistical analyses including Mann-Whitney, Chi-square, and ROC curve analyses were performed to assess diagnostic accuracy.

Main Results:

• 19% of patients (172/906) exhibited LSTV, with Type I being the most prevalent (52%).
• Significantly higher cVPVA and dVPVA were observed in patients without LSTV compared to those with LSTV or related anomalies (p < .001).
• Optimal cutoffs for cVPVA and dVPVA were established for identifying LSTV, classifying LSTV types, and differentiating L5 sacralization from S1 lumbarization.

Conclusions:

• EOS-derived cVPVA and dVPVA demonstrate strong diagnostic performance for LSTV identification and classification.
• These measurements are valuable for differentiating L5 sacralization from S1 lumbarization.
• VPVA measurements on EOS provide a reliable tool for assessing lumbosacral transitional anomalies.