Shivani Naik, M.D., Murali K.Kolikonda, M.D., Steven Lippmann, M.D.

Parkinson’s disease (PD) is well known by its cardinal motor symptoms of tremor, bradykinesia, rigidity, and postural or gait instability. Parkinsonism without tremor is frequently misdiagnosed. That PD can also induce a pain syndrome is less widely recognized. Parkinsonian pain is prevalent in 40-85% of PD patients (1). A wide range of pain syndromes are involved and are varied between early and advanced stages of the disease. Stiff shoulder, rigidity, and/or dystonia are often present in early stages, whereas radicular, musculoskeletal, or dystonic pains are present in more advanced cases of PD (2).

Shoulder pain or stiffness may even present prior to the PD diagnosis and can be the only symptom of the illness. Patients with PD can develop joint deformities and arthritic changes involving metacarpophalangeal and distal interphalangeal joints with ulnar deviation. These signs are known as striatal hand and/or foot and pseudo-rheumatoid deformities (3). Such arthritic findings often lead to misdiagnosis and inappropriate treatments. Dystonia is commonly observed in later stages and is associated with painful spasms involving feet; these might also be the only presenting symptom. Central parkinsonian pain is complex, diffuse, constant, and not confined to a dermatome.  Central pain syndromes may involve sensory pathways within the basal ganglia and the thalamocortical-basal ganglia circuits (3).

Parkinsonian types of pain are often distressing and affect people significantly at inducing a poor quality of life. In addition, depression and anxiety can precipitate pain and vice a versa. Depression is more severe in those patients with PD who experienced pain syndromes (3).

Diagnosing patients with Parkinson’s disease based on a pain symptom is challenging. Such persons are often referred to psychiatrists for unidentified pain etiologies. All physicians should include parkinsonianism in their differential diagnoses of anyone complaining with unusual pain presentations. Although pain is one of the most frequent non-motor symptoms experienced by people with PD, of those with a pain syndrome, 50% do not receive medicinal or physical therapies (3). Consideration toward contributing or initiating psychiatric etiologies can lead to better care. A comprehensive evaluation and awareness about non-motor pain symptoms could globally facilitate proper diagnosis and management of PD patients.

References

1.Truini A, Frontoni M, Cruccu G. Parkinson’s disease related pain: a review of recent findings. Journal of Neurology. 2013;260(1):330-334.

2.Hanagasi HA, Akat S, Gurvit H, Yazici J, Emre M. Pain is common in Parkinson’s disease. Clinical Neurology and Neurosurgery. 2011;113(1):11-13.

3.Ha AD, Jankovic J. Pain in Parkinson’s disease. Movement disorders : Journal of the Movement Disorder Society. 2012;27(4):485-491.