Table 2: Classification of pain in PD adapted by [89].

Musculoskeletal: aching, cramping, arthralgic, myalgic sensations in joints, and muscles; may exacerbated by parkinsonian rigidity, stiffness, and immobility, postural abnormalities, and relieved by mobility; may be associated rheumatologic and orthopaedic disease. May fluctuate with medication dosing, and improve with levodopa.
Dystonic: associated with sustained twisting movements and postures; muscular contractions often very forceful and painful; may fluctuate closely with medication dosing: wearing off dystonia, early morning dystonia, peak-dose dystonia, diphasic dystonia.
Radicular/Neuropathic: pain in a root or nerve territory, associated with motor or sensory signs of nerve or root entrapment.
Central or primary pain: burning, tingling, formication, “neuropathic” sensations, often relentless and bizarre in quality, not confined to root or nerve territory; pain may have an autonomic character, with visceral sensations or dyspnea, and vary in parallel with the medication cycle as a non-motor fluctuation; not explained by rigidity, dystonia, musculoskeletal or internal lesion.
Akathisia: subjective sense of restlessness, often accompanied by urge to move; may fluctuate with medication effect, and improve with levodopa.
Others types of pain: oral and genital pain; burning mouth or vagina syndrome; may represent a sensory wearing off and may improve with L-dopa.