The suture that separates the parietal bone from the tabular portion of the occipital bone is called?

Appeared in: AIIMS Patna NO - 2020

Explanation

The lambdoidal suture is the specific anatomical landmark that separates the parietal bones from the occipital bone.
It is located on the posterior aspect of the skull.
Its name is derived from its shape, which resembles the Greek letter lambda (λ).
The junction of the lambdoidal and sagittal sutures forms the posterior fontanelle in infants.

Option B: The frontal suture, also known as the metopic suture, is located in the midline of the frontal bone.
Option C: The sagittal suture runs along the midline of the top of the skull, but it separates the two parietal bones from each other.
Option D: The coronal suture separates the frontal bone from the two parietal bones.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Anatomy of cranial sutures as background academic context rather than a clinical decision trigger.
In neonatal assessment, the lambdoidal suture helps locate the posterior fontanelle. A sunken fontanelle can indicate dehydration, while a bulging fontanelle may suggest increased intracranial pressure.
Premature fusion of the lambdoidal suture (craniosynostosis) can cause plagiocephaly (a flattened head shape) and may require surgical intervention to allow for normal brain growth.
In trauma cases, knowledge of suture lines is essential to differentiate them from skull fractures on imaging studies.

How to Approach the Question

First, identify the key anatomical structures mentioned in the question stem: 'parietal bone' and 'occipital bone'.
The question asks for the 'suture' that separates these specific bones.
Mentally recall or visualize the anatomy of the skull and the locations of the major sutures.
Evaluate each option: The coronal suture connects frontal and parietal bones. The sagittal suture connects the two parietal bones. The frontal suture is in the frontal bone.
Conclude that the lambdoidal suture is the correct one, as it connects the parietal and occipital bones.
This is a direct factual recall question, relying on foundational anatomical knowledge.

Concept Tested & Keywords

QaUC9WlrF8ZDEHRalZe_hC

E6 Anatomy Applied Ashalatha 4e p. 278-280

E6 Anatomy Grays 43e Vol 2 Part 2 p. 4-6

Practise the full AIIMS Patna NO - 2020

Attempt every question from this paper in a timed mock, then review the full solution for each one.