Tremors in Head and Hands That Stop When Redirected: Likely Functional Neurological Disorder
The tremors in your patient's head and hands that stop when redirected are most likely due to functional neurological disorder (FND), which requires a specific rehabilitation approach focused on retraining movement patterns rather than suppressive medications.
Clinical Features of Functional Tremor
- Functional tremor is characterized by its variability in frequency and amplitude, and most importantly, its distractibility (stopping when attention is redirected) 1
- This type of tremor is the most common functional movement disorder and can be distinguished from other tremor types by specific "red flags" including suggestibility and entrainment (ability to change with external rhythmic movements) 2
- Patients often report sudden onset and remissions that may last for months or years, with the tremor sometimes only present in specific situations 2
Differential Diagnosis
- Essential tremor typically presents as a postural and kinetic tremor (4-8 Hz) that affects mainly upper extremities and head, but does not stop with distraction 3
- Parkinsonian tremor is primarily a resting tremor (4-6 Hz) that may have postural components but lacks the distractibility seen in your patient 1, 4
- Cerebellar tremor (intentional tremor) becomes more pronounced during goal-directed movements and is associated with dysarthria and ataxic gait, but doesn't typically stop with distraction 5
- Psychogenic tremor shares features with functional tremor but is considered when there is evidence of conscious symptom production 2, 4
Diagnostic Approach
- Observe for the key clinical sign of distractibility - tremor stopping when attention is redirected to another task 1
- Test for entrainment by having the patient perform rhythmic movements with an unaffected limb and observe if the tremor adopts that rhythm 2
- Look for suggestibility - whether the tremor changes in amplitude or frequency when suggested 2
- Consider neurophysiological measurements including accelerometry, which has shown high sensitivity (89.5%) and specificity (95.9%) in diagnosing functional tremor 2
Management Recommendations
- Explain to the patient that FND is a real neurological condition caused by a potentially reversible miscommunication between the brain and the body 1
- Avoid reinforcing abnormal movement patterns by minimizing attention to the tremor 1
- Implement rehabilitation strategies that focus on:
- Avoid unnecessary medications, as they may reinforce illness beliefs and cause side effects without addressing the underlying functional disorder 1
Important Considerations
- Functional tremor is not a diagnosis of exclusion - positive clinical signs like distractibility are required for diagnosis 2
- Patients experience their movements as involuntary despite sharing characteristics with voluntary actions 2
- Consider underlying psychological factors that may contribute to symptom development and exacerbation, but recognize that not all patients have obvious psychological symptoms 1
- Avoid providing adaptive equipment in the acute phase, as this may prevent improvement by reinforcing maladaptive movement patterns 1
Treatment Approach
- Psychotherapeutic treatment is indicated for functional tremor patients regardless of whether they have evident psychological symptoms 2
- Specific physiotherapeutic retraining approaches have shown benefit for functional tremor 2
- Occupational therapy focusing on normal movement patterns and redirecting attention can be helpful 1
- A 24-hour approach to therapy is recommended, implementing rehabilitation strategies throughout daily routines as part of self-management 1
Remember that functional tremor is a genuine neurological condition that requires specialized rehabilitation rather than symptomatic medication treatment. The positive sign of distractibility in your patient strongly suggests this diagnosis.