Which clinical history findings are characteristic of primary lateral sclerosis (PLS)?

Updated: Apr 28, 2014
  • Author: Hidehiro Takei, MD; Chief Editor: Adekunle M Adesina, MD, PhD  more...
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The age of onset for primary lateral sclerosis (PLS) is usually between 40 and 60 years, with spasticity in the legs accompanied by hyperactive deep tendon reflexes, clonus, and Babinski sign. Patients with spastic dysarthria as an initial symptom of PLS are also described. In contrast to ALS, the LMNs remain intact, and thus, no amyotrophy is observed. Rare cases of frontotemporal dementia with PLS have been reported. [27]

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