Morphological variations of the vertebral lamina: An anatomical and clinical review

Abstract

The vertebral laminae form the posterior component of the vertebral arch and exhibit considerable morphological variability. Understanding these variations is essential due to their clinical and surgical implications. This review summarizes the types of vertebral lamina variations, the role of imaging in their recognition, and their clinical relevance in surgery, anesthesia, trauma, neurological disorders and congenital anomalies. A literature-based narrative review was conducted focusing on studies describing laminar morphometry, congenital anomalies, imaging characteristics, and clinical outcomes. Variations include hypoplasia, aplasia, asymmetry, and non-fusion, often observed in the cervical and lumbosacral regions. Radiography provides limited detection, whereas CT offers precise morphometric data and MRI demonstrates relationships with neural structures. Clinically, laminar variations affect surgical procedures such as laminectomy and laminoplasty, influence the success of caudal epidural anesthesia, contribute to atypical fracture patterns, and are associated with anomalies such as spina bifida occulta, tethered cord, and neurological disorders including lumbar disc herniation. Vertebral lamina variations are common and clinically significant. Accurate recognition through imaging and awareness of their surgical and anesthetic implications are essential to reduce complications and improve patient outcomes.

Keywords

• Vertebral Lamina
• Anatomical Variation
• Laminectomy
• Laminoplasty

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