Muscle Atrophy, Reduced Muscle Tone, Flaccid Paresis, Focal Analgesia

Reduced muscle tone, muscle atrophy, and flaccid paresis are characteristic of peripheral nerve, muscle, or neuromuscular diseases. Signs may be localized to a single limb, as in the case of traumatic peripheral nerve injury; generalized, as in botulism and many myopathies; or multifocal, as in equine protozoal myeloencephalitis and other diseases that attack multiple areas of the CNS.

Peripheral nerve lesions, whether of the central components of the nerves in the spinal cord and brainstem or along their peripheral course in the limbs and head, can also result in focal hypalgesia or analgesia. Knowledge of the autonomous zones for the peripheral nerves innervating the limbs can be used to localize such peripheral nerve lesions.⁵⁶