Hypotonicity is common with which type of neurological lesion?

Hypotonicity is common with which type of neurological lesion?

• A. Upper Motor Neuron Lesions
• B. Peripheral Neuropathy
• C. Lower Motor Neuron Lesions
• D. Myopathy

Answer: (C)

Hypotonia is the result of reduced neural input to the muscle, so it most often shows up when the final common pathway to the muscle is damaged. Lower motor neuron lesions disrupt the firing of alpha motor neurons and the peripheral nerves that directly activate muscle fibers, leading to a drop in baseline muscle tone and often decreased reflexes and atrophy. In contrast, upper motor neuron lesions remove inhibitory control from higher centers, which typically produces increased tone—spasticity or rigidity—over time, even though there can be brief flaccidity early on. Peripheral neuropathy and myopathy involve nerves outside the spinal cord or the muscle tissue itself, respectively; while they can cause weakness and reduced reflexes, the classic neurological lesion associated with hypotonia is a lower motor neuron lesion.

Hypotonia is the result of reduced neural input to the muscle, so it most often shows up when the final common pathway to the muscle is damaged. Lower motor neuron lesions disrupt the firing of alpha motor neurons and the peripheral nerves that directly activate muscle fibers, leading to a drop in baseline muscle tone and often decreased reflexes and atrophy.

In contrast, upper motor neuron lesions remove inhibitory control from higher centers, which typically produces increased tone—spasticity or rigidity—over time, even though there can be brief flaccidity early on. Peripheral neuropathy and myopathy involve nerves outside the spinal cord or the muscle tissue itself, respectively; while they can cause weakness and reduced reflexes, the classic neurological lesion associated with hypotonia is a lower motor neuron lesion.