NPH is pathological ventriculomegaly with normal opening pressures on lumbar puncture. The classic triad includes gait disturbance, dementia, and urinary incontinence.

A 68-year-old male presented with progressively worsening gait and balance difficulties for the past 7 months. An episode begins with regular walking, followed by a gradual increase in pace, which he described as “I just felt like running” and ultimately falls. While running, he states ‘I have no control over these legs’ and is unable to stop, until he falls. The episode can recur when he tries to start walking again and can occur on a straight surface or a slope. He once ran backward up a slope while he had no intention of doing this and was unable to stop until he fell. . He has difficulty standing up from a deep seat, requiring multiple attempts and tends to drag his feet on the floor while walking which he corrects by telling himself to pick his feet off the ground, though his attempts fail. He admits to urinary urgency but denies incontinence and has mild memory problems like remembering familiar people’s names. Neurological examination was remarkable for hyperreflexia in extremities, akinetic rigid parkinsonism worse on the right, and peripheral neuropathy. A magnetic resonance imaging (MRI) brain showed central parenchymal loss with prominent ventricles. We diagnosed him with NPH for which he underwent three successive therapeutic spinal taps and showed objective improvement in his gait.

NPH is a potentially reversible syndrome if caught early and MRI can help with an accurate diagnosis of the condition. To the best of our knowledge, the gait disturbance of involuntary running in our case has never been described in association with NPH. Since the patient described it as “I just felt like running”, we named it the “Gump” sign.