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Psychogenic axial myoclonus: report on two cases
Jarosław Sławek1, Hubert M Wichowicz, Wiesław Jerzy Cubała
1Department of Neurology, St. Adalbert Hospital, Gdańsk, Poland.
Summary
Psychogenic axial myoclonus, mimicking propriospinal myoclonus, can occur without central nervous system lesions. Two patients recovered fully with psychoeducation and medication, highlighting a novel presentation of psychogenic movement disorders.
Area of Science:
- Neurology
- Psychiatry
- Movement Disorders
Background:
- Axial myoclonus (AM) involves axial and proximal muscle jerks, including propriospinal myoclonus (PSM).
- PSM is characterized by trunk flexion/extension jerks originating in axial muscles and spreading slowly along propriospinal pathways.
- The organic basis of AM and PSM is typically investigated through neuroimaging and electrophysiology.
Observation:
- Two patients presented with flexion-dominant axial myoclonus.
- No structural central nervous system lesions or organic electrophysiological findings were identified.
- A diagnosis of conversion disorder was made for both patients.
Findings:
- Both patients experienced complete resolution of myoclonic jerks following psychoeducation.
- Patients remained symptom-free during a 6-year follow-up period.
- The cases were diagnosed as psychogenic axial (propriospinal-like) myoclonus, fulfilling psychogenic movement disorder criteria.
Implications:
- This study suggests psychogenic axial myoclonus, presenting with a PSM-like phenotype, is a potential, albeit rare, manifestation of conversion disorder.
- The findings underscore the importance of considering psychogenic etiologies in movement disorders lacking objective organic evidence.
- Successful treatment with psychoeducation and psychotropic medication indicates a favorable prognosis for this condition.
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