Loss of pain and temperature sensation occurs on which sides of the body in Wallenburg syndrome?

• A. Contralateral body and ipsilateral face
• B. Contralateral face and ipsilateral body
• C. Both sides of the body
• D. None

Answer: (A)

Wallenberg syndrome, also known as lateral medullary syndrome, typically results from a vascular insult to the lateral part of the medulla oblongata. This condition is characterized by a specific pattern of neurological deficits due to the disruption of pathways involved in sensory and autonomic functions.

In this syndrome, the loss of pain and temperature sensation occurs contralaterally in the body and ipsilaterally in the face. This occurs because of the way sensory pathways are organized. The spinothalamic tract, which carries pain and temperature sensations, crosses to the opposite side of the body at the level of the spinal cord. Thus, an injury affecting this tract leads to loss of these sensations on the opposite side of the body (contralateral). On the other hand, the trigeminal nerve, which carries similar sensory information from the face, remains on the same side (ipsilateral). This anatomical arrangement results in the distinctive sensory deficits seen in Wallenberg syndrome, making the identification of the correct answer straightforward.