Damage to which artery is likely to present with contralateral arm and leg weakness and ipsilateral tongue deviation?

The correct answer relates to the specific vascular territories affected by damage to the artery in question. The scenario describes contralateral arm and leg weakness along with ipsilateral tongue deviation, which suggests that the area of the brain responsible for motor function is impacted, particularly the motor pathways that control these functions.

Damage to the vertebral artery would affect the posterior brainstem, specifically the medulla oblongata. This area houses the descending corticospinal tract and the hypoglossal nucleus. The corticospinal tract controls voluntary movement and decussates (crosses) at the junction of the medulla and spinal cord, meaning that damage to this area leads to contralateral weakness (arm and leg on the opposite side of the lesion). Furthermore, the hypoglossal nerve, which innervates the tongue, is located in the medulla. Damage to the hypoglossal nucleus results in weakness of the ipsilateral tongue muscles, leading to deviation of the tongue toward the side of the lesion.

In summary, the combination of signs—contralateral weakness in the limbs and ipsilateral deviation of the tongue—indicates a classic presentation consistent with damage to the vertebral artery and its supply to the brainstem structures involved in these functions