Hyperreflexia

Hyperactive deep tendon reflexes (DTRs) is a sign of upper motor neuron (UMN) lesions. It is also commonly seen in normal but anxious people. The proper technique of deep tendon reflex examination and experience play a major role in eliciting and categorizing DTRs. Sustained clonus is the highest degree of hyperreflexia. The most important neuromuscular disease associated with hyperreflexia is amyotrophic lateral sclerosis (ALS) due to degeneration of the cortical motor neurons. Diagnostic difficulty occurs when hyperreflexia and spasticity are the only findings. In these cases, primary lateral sclerosis (PLS), hereditary spastic paraplegia (HSP), and other causes of myelopathies should be entertained. Compressive myelopathies are easily excludable by neuroimaging.