Biceps pain as the presenting symptom of Parkinson disease: effective treatment with L-dopa.

Abstract: Parkinson disease can present remarkably as shoulder pains that may long precede the clinical diagnosis. A case is presented in which, during a 2-year period, both lower biceps brachii became exquisitely painful, with both the pain and the "frozen shoulders" responding promptly to the initiation of L-dopa therapy.

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Even rheumatologists and neurologists poorly appreciate the occurrence of pain in Parkinson disease. In recent years, however, there have appeared several reports (1-5) emphasizing that Parkinson disease can become painful and that pain can long precede the diagnosis of Parkinson disease. The patient in the present case, presenting with 2 years of severe bilateral lower biceps pain, had undergone fruitless evaluations elsewhere for "frozen shoulders," and it was only the development of a right foot tremor that led to neurologic evaluation and clearing of the shoulder pain with L-dopa therapy.

Case Report

A 65-year-old woman complained of bilateral arm pains and a tremor of the right foot of 2 years' duration. She had a history of arthritis involving her hands and hips, and had undergone left hip replacement in 1989. Lower biceps pain first occurred on reaching out with her right arm and constantly limited her range of motion; it spread to the left arm in a similar proximal location, making it difficult for her to do her hair, reach upward or behind her neck, or fold clothes. At times, pain became excruciating, but it remained concentrated over the lower biceps areas, and there was no pain in the forearms, hands, or lower extremities. Over this 2-year period, she also developed a resting tremor of the right foot. Her stance and gait became increasingly unsteady, and she arose with difficulty from deep chairs or sofas.

Only when reinforcement was used was there apparent a slight cogwheeling nuchal and bilateral elbow rigidity, nor was there resting tremor of the arms or rigidity of the legs, but a moderate rhythmical resting right foot tremor disappeared on intention. She was left-handed, and her fine finger and toe movements were bilaterally impaired. A mild flexion dystonia and inversion at the right ankle were not associated with any weakness. Although stepping out well, she walked with mildly flexed elbows and without arm swing.

Normal laboratory studies included erythrocyte sedimentation rate, serum creatinine phosphokinase, serum immunoelectrophoresis, antinuclear antibody, vitamin [B.sub.12] and folic acid levels, cardiolipin, and Sjogren and DNA antibodies, but the homocysteine level was elevated at 14.8 [micro]mol/L. Radiographs of her shoulders showed only mild degenerative changes about the acromioclavicular joints, and other normal studies included brainstem auditory evoked response, electroencephalography, magnetic resonance imaging of the brain, and a Mini-Mental State Examination score of 30 (with MQ of 161 and IQ of 113, and with verbal IQ of 114 and performance IQ of 108).

On a regimen of carbidopa/L-dopa 25/100-mg tablets administered four times per day, she quickly noted both a distinctly improved energy level and a remarkably increased range of motion at her shoulders and arms, together with virtually complete clearing of biceps pain. She was able to reach out for objects and could again do her own hair. Examination found no cogwheeling nuchal rigidity and only minimal cogwheeling elbow rigidity with reinforcement.

Discussion

Over a 2-year period, this patient had become increasingly disabled by pains in the lower biceps areas that were markedly intensified by reaching and that greatly limited her shoulder range of motion. The pains began asymmetrically, but became symmetric, similar to the usual course of parkinsonian rigidity. However, formal testing found only a slight bilateral cogwheeling elbow rigidity, and there was no tremor of the hands or arms; the only distinctly parkinsonian sign was a resting rhythmic tremor of the right foot. The immediate and virtually complete response of her shoulder pain to L-dopa therapy was gratifying and persistent.

In the course of a 37-year neurologic practice that has included a large number of patients with Parkinson disease, I had never previously seen a patient present because of pain. A computerized literature search surprisingly found the article "Shoulder Pain in Patients with Parkinson Disease," (1) in which pain is suggested to be especially common in patients with akinesia and rigidity but without tremor. My patient, indeed, lacked upper extremity tremor, but also lacked akinesia and had only minimal rigidity at the elbows, the site customarily tested in the upper extremities; because of severe pain, she could not tolerate testing for shoulder rigidity before L-dopa therapy was begun. Her shoulder pain first occurred on the side of her first parkinsonian symptom (right foot tremor). The pain was clearly neither mechanical nor inflammatory, but pathophysiologic, and may have reflected localized parkinsonian rigidity so severe as to restrict and render painful range of motion. Shoulder stiffness may be one of the more common musculoskeletal afflictions in Parkinson disease, and it may be the initial manifestation. (5)

Pain is rarely mentioned in textbook descriptions of the clinical phenomena of Parkinson disease, but several recent authors have described it. (3-5) It has been inappropriately labeled "reflex sympathetic dystrophy syndrome of the shoulder," and may antedate parkinsonian motor symptoms by at least 2 years. (4) A recent study of 50 patients with Parkinson disease found 7 with symptoms of "pain/sensory," but pain distribution was not further categorized. (2) Pain localization may prove diagnostically helpful: in my patient, it was quite focal, involving the distal biceps areas and sparing the shoulders themselves, the elbows, the forearms, and the hands. In addition to dopaminergic therapy, exercises and physical therapy can be helpful, but the lower biceps pain in my patient was clearly not a manifestation of frozen shoulder and improved promptly on initiation of dopaminergic therapy. The syndrome of biceps pain in Parkinson disease deserves better recognition. It can clearly precede the onset of clinically recognized Parkinson disease by 2 years or longer, can become severe and quite disabling, but responds rapidly and well to dopaminergic therapy.

Accepted July 14, 2003.

References

1. Vaserman-Lehuede N, Verin M. Shoulder pain in patients with Parkinson disease. Rev Rhum Engl Ed 1999;66:220-223.

2. Witjas T, Kaphan E, Azulay JP, et al. Nonmotor fluctuations in Parkinson disease: Frequent and disabling. Neurology 2002;59:408-413.

3. Waseem S, Gwinn-Hardy K. Pain in Parkinson disease: Common yet seldom recognized symptom is treatable. Postgrad Med 2001;110:33-34, 39-40, 46.

4. Serratrice G, Michel B. Pain in Parkinson disease patients. Rev Rhum Engl Ed 1999;66:331-338.

5. Ford B. Pain in Parkinson disease. Clin Neurosci 1998;5:63-72.

RELATED ARTICLE: Key Points

* Parkinson disease can present as pain in the upper extremities.

* The pain of Parkinson disease may lead to fruitless evaluations for "frozen shoulder."

* The limb pains of Parkinson disease may be asymmetric or symmetric, and particularly involve the shoulder areas and biceps muscles.

* The pain often responds quickly and fully to treatment with L-dopa/carbidopa.

Gordon J. Gilbert, MD

From the Department of Physiology and Biophysics, University of South Florida School of Medicine, Tampa, FL.

Reprint requests to Gordon J. Gilbert, MD, 500 Pasadena Avenue S., St. Petersburg, FL 33707. Email: [e-mail]