Hordeum pusillum

Hoover's Sign is a physical examination finding that is used in the medical field to differentiate between organic and functional paralysis. It was named after Charles Franklin Hoover, an American physician who first described the sign in 1908.

Definition

Hoover's Sign refers to a phenomenon where, in a patient with hysterical paralysis, the downward pressure exerted by the heel of the "paralyzed" leg increases when the patient is asked to raise the contralateral leg. This is due to the involuntary contraction of the hip extensor muscles on the "paralyzed" side, which occurs as a compensatory mechanism when the patient attempts to raise the other leg.

Clinical Significance

Hoover's Sign is primarily used to distinguish between organic and functional paralysis. Organic paralysis, caused by actual physical damage to the nervous system, will not exhibit Hoover's Sign. In contrast, functional paralysis, which is psychological in origin, will exhibit the sign. This is because the subconscious compensatory contraction of the hip extensor muscles on the "paralyzed" side indicates that the nervous pathways are intact, suggesting a functional cause for the paralysis.

Limitations

While Hoover's Sign is a useful tool in the differential diagnosis of paralysis, it is not infallible. Some patients with organic disease may still exhibit the sign, and some patients with functional paralysis may not. Therefore, it should be used in conjunction with other diagnostic tools and not as a standalone test.

See Also

• Physical examination
• Paralysis
• Hysteria
• Charles Franklin Hoover

References

• Hoover, C. F. (1908). A new sign for the detection of malingering and functional paresis of the lower extremities. The Journal of the American Medical Association, 51(13), 1055-1056.