Hoover's Sign: The Medical Term for Feigning Weakness During a Neurological Examination
The medical term for when someone is trying to fake weakness on one side of the body during a neurological examination is "Hoover's sign," which is used to detect factitious or nonorganic weakness. 1
Understanding Factitious Disorders vs. Malingering
When evaluating patients with apparent unilateral weakness, it's important to distinguish between several conditions:
- Factitious disorder: Intentional production of symptoms without obvious external gain, where the motivation is to assume the sick role 1
- Malingering: Intentional fabrication of symptoms for external gain (financial compensation, avoiding work/military duty, obtaining medications) 2
- Functional neurological disorder: Genuine neurological symptoms that cannot be explained by traditional neurological disease but are not intentionally produced 3
Hoover's Sign: Detection Method
Hoover's sign is a specific clinical test to detect nonorganic weakness:
- Technique: The examiner places one hand under the heel of the "weak" leg while asking the patient to push down with the "normal" leg against resistance 1
- Positive sign: When pushing with the good leg, the examiner feels involuntary downward pressure from the supposedly weak leg 1
- Interpretation: This indicates that the weakness is nonorganic, as true hemiparesis would not produce this counterforce 1
Other Signs of Nonorganic Weakness
Several other examination findings can help identify factitious weakness:
- Give-way weakness: Inconsistent strength with sudden giving way during resistance testing 1
- Drift without pronation: In true hemiparesis, a drifting arm typically pronates 1
- Non-anatomical patterns: Weakness that doesn't follow known neurological pathways 1
- Inconsistent performance: Variable strength when tested repeatedly or in different contexts 1
Clinical Context and Differential Diagnosis
When evaluating possible factitious weakness, consider:
- Somatic symptom disorder: Excessive thoughts, feelings, or behaviors related to somatic symptoms (previously called psychogenic disorders) 1
- Conversion disorder: Neurological symptoms that are not compatible with recognized neurological diseases but are not intentionally produced 1
- PNES (Psychogenic Non-Epileptic Seizures): Often co-occur with other functional neurological symptoms 1
Management Approach
When factitious weakness is suspected:
- Avoid direct confrontation: Accusatory approaches may lead to patient withdrawal or escalation of symptoms 4
- Document objectively: Record specific findings like Hoover's sign rather than subjective impressions 2
- Multidisciplinary approach: Involve psychiatry early when factitious disorder is suspected 5
- Supportive confrontation: Present inconsistencies in a non-judgmental manner while offering continued care 4
- Address underlying issues: Focus on coping strategies and functional improvement rather than symptom validity 4
Common Pitfalls to Avoid
- Premature labeling: Avoid diagnosing malingering without sufficient evidence 3
- Missing comorbidities: Patients with factitious disorders may also have genuine medical conditions 5
- Excessive testing: Repeated unnecessary investigations can cause iatrogenic harm 5
- Delayed recognition: Failure to identify factitious disorders can lead to harmful interventions 4
Special Considerations
- Healthcare workers: May be more likely to present with factitious disorders but are often diagnosed with "hysteria" instead 6
- Military context: Special attention should be paid to potential secondary gain in military settings 2
- Documentation: Careful documentation is essential but should avoid pejorative language 4