Thoracic nerves are -

Appeared in: RUHS, Jaipur, PB B.Sc Nursing Entrance-2024

Explanation

12 pairs.
The spinal cord is divided into segments, each giving rise to a pair of spinal nerves. There are 31 pairs in total.
The thoracic region of the spine has 12 vertebrae (T1-T12), and a pair of spinal nerves emerges from each level, resulting in 12 pairs of thoracic nerves.
These nerves primarily function to innervate the chest wall, intercostal muscles, and parts of the upper abdomen.

Option A: This is the number of cervical spinal nerves, not thoracic.
Option C: This is the number of lumbar and sacral spinal nerves, not thoracic.
Option D: This number does not correspond to any of the major groups of spinal nerves.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Anatomy of the peripheral nervous system, specifically the number of thoracic spinal nerves as background academic context rather than a clinical decision trigger.
Thoracic nerves T1-T12 are also known as intercostal nerves. They supply sensation to the skin of the chest and abdomen, as well as motor function to the intercostal and abdominal muscles.
Irritation or damage to a thoracic nerve can cause pain, numbness, or weakness in a band-like distribution around the chest or abdomen, a condition known as thoracic radiculopathy.
What if? A patient presents with a painful, blistering rash in a band on one side of their chest. This pattern follows a thoracic dermatome and is a classic sign of herpes zoster (shingles), caused by the reactivation of the varicella-zoster virus in a single dorsal root ganglion of a thoracic nerve.

How to Approach the Question

First, identify the question as a factual recall question about human anatomy.
Recognize that 'thoracic nerves' are one of the five groups of spinal nerves that branch off the spinal cord.
Recall the total number of spinal nerve pairs (31) and their distribution.
Mentally list or use a mnemonic to remember the number of pairs in each group: Cervical (8), Thoracic (12), Lumbar (5), Sacral (5), and Coccygeal (1). A common mnemonic is to think of meal times: 8 (breakfast), 12 (lunch), 5 (dinner).
Select the option that correctly matches the number of thoracic nerve pairs.

Concept Tested & Keywords

Concept Tested: Anatomy of the peripheral nervous system, specifically the number of thoracic spinal nerves.
Stem keywords: Thoracic nerves
Lead-in keywords: BEST, MOST RELEVANT CLUE
Negative lead-in flag: false

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E6 Anatomy Grays 43e Vol 1 Part 3 pp. 33-35, 64-66

E6 Anatomy Grays 43e Vol 2 Part 2 p. 47-49

Practise the full RUHS, Jaipur, PB B.Sc Nursing Entrance-2024

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