Rigidity, while seldom the main symptom early in Parkinson’s, is experienced as a stiffness of the arms or legs beyond what would result from normal aging or arthritis. Some people call it “tightness” in their limbs. Stiffness can occur on one or both sides of the body and contribute to a decreased range of motion. This can lead to problems with achiness or pain in the muscles or joints affected.
Many people with PD will have a reduced arm swing when walking, more so on the most affected side. Rigidity of the trunk is also possible, as is stiffness of the facial muscles, which contributes to facial masking.
Rigidity can also negatively impact sleep quality. Stiffness in the late evening and poor mobility in bed can make it hard to fall and stay asleep at night.
Rigidity is one of three telltale symptoms that help doctors make a Parkinson’s diagnosis. The other two are slowness of movement (bradykinesia) and tremor.