North American Veterinary Licensing Examination (NAVLE) Practice Test

The presence of hypotonic forelimbs and spastic paresis in the hindlimbs is indicative of a specific neurological condition that can be linked to a lesion at the cervicothoracic area (C6-T2). In this case, the hypotonia in the forelimbs suggests that there may be a disruption in the lower motor neurons or peripheral nerves that innervate those limbs. This is typically associated with a spinal cord lesion in the cervical region affecting the lower motor neurons that influence the forelimbs.

Additionally, the spastic paresis seen in the hindlimbs indicates that there may be concurrent upper motor neuron involvement in this area, which points to a lesion located higher in the spinal cord. Since the hypotonicity is affecting the forelimbs while spasticity is present in the hindlimbs, the lesion is likely located within the cervicothoracic junction, where both the cervical spinal nerves innervating the forelimb and the neuronal pathways that affect the hindlimb exist.

In contrast, lesions in the cranial cervical region (C1-C5) would generally affect all four limbs, causing tetraparesis rather than a differential effect on the forelimbs and hindlimbs. Thor