AISTI > Neurology for vets > Monoparesis

Monoparesis

LOCALISATION OF THE LESION IN THE PATIENT WITH MONOPARESIS

The monoparesis in the front limbs is most commonly caused by the diseases of the peripheral nerve(s) or nerve roots. The diseases of endplates or muscles affecting just one limb are very rear. Diseases of the spinal cord in the cervical area usually cause hemiparesis or tetraparesis. Therefore, monoparesis in the front limb is usually caused by the lesion in nerves or nerve roots of the affected limb.

Monoparesis in the hind leg is also usually caused by nerve or nerve root lesion. It can be outside the spinal canal (peripheral nerve) or inside the canal (cauda equina). Additionally, also unilateral spinal cord lesions caudal to Th2 can cause monoparesis in the rear extremity. This is the exception from the general localization scheme. Vascular lesions are the most often causes of such unilateral spinal cord diseases (ex. fibrocartilaginous embolism).

DIFFERENTIAL DIAGNOSES OF THE MONOPARESIS

Vascular Fibrocartilaginous embolism, ischemic encephalopathy (D,C)

Inflammatory-infectious Plexus brachialis neuritis (D,C)

Traumatic Trauma (neuropraxia, axonotmesis, neuronotmesis) of plexus brachialis or isolated nerve(s) (D,C)

Anomalous -

Metbolic Hypothyroidism (D)

Idiopathic -

Neoplastic Primary: malignant nerve sheath tumor (D,C). Secondary: lymphoma, skeletal tumors (D,C)

Degenerative Lateralised disk herniation, degenerative foraminal stenosis causing nerve root compression (nerve root signature)

PS: D-dog, C-cat.