Clinical Scorecard: Exploring the Diverse Gait Phenotypes in Normal Pressure Hydrocephalus Beyond Lower Body Parkinsonism

At a Glance

Key Highlights

• NPH gait disturbance extends beyond classic lower body parkinsonism to a spectrum of gait phenotypes with variable shunt responsiveness.
• Shunt surgery significantly improves gait, cognitive domains (verbal learning, memory, psychomotor speed), urinary urgency, and postural stability.
• Upper limb motor function is also affected in NPH and may be assessed with tests like Finger Tapping Test to predict shunt responsiveness.

Guideline-Based Recommendations

Diagnosis

• Identify NPH by Hakim-Trias: gait disturbance, cognitive impairment, urinary incontinence.
• Assess gait phenotype diversity beyond typical frontal gait disorder.
• Evaluate cognitive domains including attention, memory, executive function, and psychomotor speed.
• Use motor function tests such as Grooved Pegboard and Finger Tapping for upper limb assessment.

Management

• CSF diversion via shunt surgery is the gold standard treatment with up to 85% improvement rates.
• Target gait disturbance as primary symptom responsive to shunting.
• Address cognitive impairment and urinary symptoms as part of comprehensive management.
• Consider upper limb motor function testing to guide treatment decisions.

Monitoring & Follow-up

• Monitor gait improvement post-shunting, noting variability by gait phenotype.
• Assess cognitive function domains longitudinally, focusing on verbal learning and psychomotor speed.
• Evaluate urinary urgency and incontinence symptoms for responsiveness to shunt therapy.
• Track postural stability and upper limb motor function improvements after surgery.

Risks

• Potential variability in shunt responsiveness depending on gait phenotype.
• Incomplete improvement in some cognitive domains such as executive function.
• Limited data on urinary incontinence facets and upper limb motor function responsiveness.

Patient & Prescribing Data

Patients with Normal Pressure Hydrocephalus exhibiting gait, cognitive, urinary, and motor symptoms

Shunt surgery leads to significant improvement in gait, cognitive function, urinary symptoms, postural stability, and upper limb motor function, with variability depending on symptom phenotype

Clinical Best Practices

• Perform comprehensive gait assessment recognizing diverse phenotypes beyond lower body parkinsonism.
• Use standardized cognitive and motor tests to evaluate symptom domains pre- and post-shunting.
• Incorporate upper limb motor function tests such as Finger Tapping Test for predicting shunt responsiveness.
• Monitor urinary symptoms carefully and consider their improvement as part of treatment success.
• Recognize postural instability as a multifactorial symptom potentially improved by shunting.

References

• Hakim-Trias symptoms in NPH
• Diverse gait phenotypes in NPH
• Shunt surgery outcomes in NPH
• Cognitive domains affected in NPH
• Urinary incontinence and shunt responsiveness
• Postural instability in NPH
• Upper limb motor function tests in NPH