Clinical Analysis of Psychogenic Movement Disorders

Choi, Sun Ah; Lee, Hyun Jeong; Lee, Myung Sik

Abstract

BACKGROUND: Psychogenic movement disorders (PMD) are not easily distinguished from other organic diseases. We attempted to discover the important clinical clues for the correct diagnosis of PMD.
METHODS
In our study, we include-ed patients who visited Youngdong Severance Hospital due to movement disorders from 1994 to 1998. Using medical records and video tape recordings, we performed a retrospective evaluation of the patients with PMD. We included documented and clinically established PMD according to degree of certainty of the diagnosis of PMD ( by Fahn, 1994).
RESULTS
Twenty-five (1.6%) of 1520 consecutive patients with movement disorders were diagnosed with documented or clinically established PMD. They presented a variety of movement disorders including tremors (60%), dystonia (16%), myoclonus (12%), chorea (4%), parkinsonism (4%), and isolated gait problems (4%). The precipitating factors were reported by 23 of the 25 (92%) patients, and 16 (64%) patients were suspected to enjoy secondary gains. Ten of the 11 patients underwent a distractibility test, 15 of 17 patients underwent placebo trials, and 3 of 5 patients underwent an one-way mirror observation showing significant and dramatic amelioration of their symptoms. Long-term psychi-atric treatment was effective in 4 of 9 patients.
CONCLUSIONS
In patients who are suspected to have PMD by the pres-ence of causative factors, acute onset, incongruity, inconsistency, and presence of secondary gain, efforts to provide objective evidence for the diagnosis of PMD must be made. Many of the patients with PMD refused psychiatric evalua-tion. Half of the patients improved through psychiatric treatment.