Which clinical manifestation is indicative of unilateral Parkinsonian tremors?

The manifestation that is indicative of unilateral Parkinsonian tremors is tremors at rest. In Parkinson's disease, one of the hallmark features is the presence of resting tremors, which are often most noticeable while the affected person is at rest and can diminish with purposeful movement. These tremors typically begin unilaterally, affecting one side of the body before potentially progressing to the other side as the disease advances.

This characteristic is crucial for differentiation from other types of tremors or conditions, as resting tremors are specifically associated with the dopaminergic neuron loss in the substantia nigra, a key aspect of Parkinson's pathology. The tremors can often be described as a "pin-rolling" movement, especially involving the fingers, and may not be accompanied by significant weakness or joint stiffness at this early stage.