Related Experiment Video
Updated: Aug 4, 2025
12:59
Three and Four-Dimensional Visualization and Analysis Approaches to Study Vertebrate Axial Elongation and Segmentation
Published on: February 28, 2021
3.8K
Thoracolumbar transitional vertebrae: Quantitative differentiation and associated numeric variation in the vertebral
Anneli M Poolman1,2, Quenton Wessels1, Albert Van Schoor2
1Division of Anatomy, School of Medicine, University of Namibia, Windhoek, Namibia.
Journal of Anatomy
|April 6, 2023
Summary
Thoracolumbar transitional vertebrae (TLTV) are found in 35% of individuals and often associate with spinal numeric variations. Quantitative analysis effectively distinguishes TLTV from typical T12 and L1 vertebrae.
Area of Science:
- Anatomy
- Anthropology
- Radiology
Background:
- Transitional vertebrae at the thoracolumbar region, known as thoracolumbar transitional vertebrae (TLTV), exhibit features of both thoracic and lumbar vertebrae.
- Discrepancies in TLTV classification, identification, and clinical relevance have persisted since their initial description 40 years ago.
- Vertebral body levels are critical anatomical references, and variations can lead to clinical errors, with previous studies suggesting a link between numeric variations and TLTV.
Purpose of the Study:
- To identify the types of TLTV and associated numeric variations in the vertebral column.
- To validate a quantitative morphometric technique for differentiating TLTV from T12 and L1 vertebrae.
- To assess TLTV prevalence and its association with spinal numeric variations in a South African population.
Main Methods:
- Analysis of skeletal remains (n=187) from the Pretoria bone collection.
- Quantitative measurement of the superior zygapophyseal process angles for T12, L1, and identified TLTV.
- Statistical analysis to determine confidence intervals for each vertebral type and assess associations with numeric variations.
Main Results:
- A prevalence of 35% (n=66/187) for TLTV was observed in the studied population.
- Distinct confidence intervals were established for T12 (187°-189.6°), L1 (109.2°-111.3°), and TLTV (130.4°-139.1°).
- Seventy percent of TLTV cases were associated with homeotic and meristic numeric variations in the spine.
Conclusions:
- Quantitative morphometric analysis, specifically measuring the superior zygapophyseal process angle, effectively differentiates TLTV from T12 and L1 vertebrae.
- The high prevalence of TLTV (35%) and its strong association with spinal numeric variations underscore its clinical significance.
- This validated technique aids in accurate identification of TLTV, crucial for avoiding errors in anatomical referencing and clinical practice.
Related Concept Videos
01:16Vertebral Column: Regions and Curvature
3.8K
The vertebral column or spine is a flexible column that supports the head, neck, and body and allows for their movements. It also protects the spinal cord.
Regions of the Vertebral Column
In an adult, the spine is subdivided into five regions: the cervical, the thoracic, the lumbar, the sacral, and the coccygeal region. The spine initially develops as a series of 33 vertebrae; after 20 years of age, the nine bones in the sacral region, five sacral, and four coccygeal bones fuse to form...
Regions of the Vertebral Column
In an adult, the spine is subdivided into five regions: the cervical, the thoracic, the lumbar, the sacral, and the coccygeal region. The spine initially develops as a series of 33 vertebrae; after 20 years of age, the nine bones in the sacral region, five sacral, and four coccygeal bones fuse to form...
3.8K
01:09Changes in the Appendicular Skeleton with Age
2.1K
The upper and lower limb initially develops as a small bulge called a limb bud, which appears on the lateral side of the early embryo. The upper limb bud appears near the end of the fourth week of development, with the lower limb bud appearing shortly after.
Initially, the limb buds consist of a core of mesenchyme covered by a layer of ectoderm. The ectoderm at the end of the limb bud thickens to form a narrow crest called the apical ectodermal ridge. This ridge stimulates the underlying...
Initially, the limb buds consist of a core of mesenchyme covered by a layer of ectoderm. The ectoderm at the end of the limb bud thickens to form a narrow crest called the apical ectodermal ridge. This ridge stimulates the underlying...
2.1K
01:18Classification of Bones
5.8K
The bones of the human skeletal system are of varied shapes, sizes, and functions. They can be classified based on their shape and function into four major classes: long bones, short bones, flat bones, and irregular bones. Some classifications include a fifth type, the sesamoid bones, as a separate class, whereas others categorize them under short bones.
Long and Short Bones
The appendicular skeleton, particularly the upper and lower limbs, is primarily made of long and short bones. The...
Long and Short Bones
The appendicular skeleton, particularly the upper and lower limbs, is primarily made of long and short bones. The...
5.8K
01:30General Structure of a Vertebra
3.1K
A typical vertebra, with the exception of the sacrum and coccyx, consists of a body, a vertebral arch, and seven different projections termed processes. The anterior portion of the vertebrae, the body, supports about half the body’s weight. The vertebral bodies progressively increase in size and thickness from the cervical region to the lumbar region of the vertebral column. The intervertebral discs present between the bodies of adjacent vertebrae firmly unites them, forming a continuous...
3.1K