In this article
Hoover's sign is a physical examination test that is used to distinguish between organic and non-organic weakness in the lower extremities. The test is named after Dr Charles Franklin Hoover, who first described it in 1908. Dr Hoover also has a second test named after him, confusingly also called Hoover's sign for COPD and relates to rib movement.
It is performed by having the patient lie supine and then asking them to flex the hip of the unaffected leg against resistance. If the patient has an organic weakness, the examiner will feel pressure on the heel of the affected leg as the patient involuntarily extends the hip to compensate for the weakness. If the patient has a non-organic weakness, the examiner will not feel any pressure on the heel of the affected leg.
Hoover's test has been shown to be a reliable and valid test for detecting non-organic weakness in people with MS. In one study, Hoover's test had a sensitivity of 92% and a specificity of 95% for detecting non-organic weakness in people with MS. This means that the test was able to correctly identify non-organic weakness in 92% of cases and correctly identify organic weakness in 95% of cases.
Non-organic weakness is a type of weakness that is not caused by a physical injury or disease. It is often seen in people with multiple sclerosis (MS) and other neurological conditions. Non-organic weakness can be caused by a variety of factors, including psychological problems, malingering, and factitious disorder.
People with non-organic weakness often complain of weakness in their limbs, but when tested, they are able to perform tasks that would be impossible if they were truly weak. For example, they may be able to walk unaided into the clinic room, but they will complain of weakness when testing the knee extensors.
A positive Hoover's test is indicated by a feeling of pressure under the heel of the affected leg when the patient is asked to flex the hip of the unaffected leg against resistance.
A negative Hoover's test is indicated by no feeling of pressure under the heel of the affected leg when the patient is asked to flex the hip of the unaffected leg against resistance.
Hoover's test is a simple and noninvasive test that can help diagnose non-organic weakness in people with MS. It is a valuable tool for clinicians trying to distinguish between organic and non-organic weakness, as it can help avoid unnecessary investigations and treatments.