Fourth Thoracic Vertebra T4, Lateral View

Description

Seen in lateral profile, the male fourth thoracic vertebra (T4) sits within the mid thoracic kyphosis between T3 superiorly and T5 inferiorly, with the intervertebral discs forming the intervening spaces. The vertebral body lies anterior to the vertebral arch, while the spinous process projects posteriorly and slightly inferiorly in keeping with typical thoracic morphology. Superior and inferior articular processes are identifiable at the junction of pedicle and lamina, forming the zygapophysial joints that align in a largely coronal plane through this region. Rib-related landmarks are implied at this level, including the costal facets on the vertebral body and transverse process, positioned lateral to the body and posterior elements. T4 is a useful reference level in both surface anatomy and spine biomechanics, since it approximates the transverse thoracic plane used to localize the sternal angle and second costal cartilage, a starting point for counting ribs and intercostal spaces during chest tube placement or auscultation. Thoracic facet orientation also shapes motion, limiting flexion and extension while allowing some axial rotation, and that becomes clinically relevant when interpreting mid thoracic pain patterns or evaluating degenerative facet arthropathy. Small changes in disc height at T3 to T5 can shift local kyphosis. Alignment matters. Educators can place this lateral view into thoracic spine modules to teach vertebral regional characteristics, zygapophyseal joint relationships, and how disc spaces contribute to curvature from cervical lordosis through sacrum. It also fits well in orthopedic and neurosurgical teaching materials that compare thoracic versus lumbar mechanics, or in radiology atlases as a visual bridge to sagittal CT and MRI anatomy at mid thoracic levels. Anatomical accuracy verified by SciePro's Medical Advisory Board.