Hoover’s sign¹ is a manoeuvre aimed to separate organic from non-organic paresis of the leg. The sign relies on the principle of synergistic contraction. Involuntary extension of the “paralysed” leg occurs when flexing the contralateral leg against resistance. It has been neglected, although it is a useful clinical test.

The patient lies supine, the examiner’s hand is placed under the non-paralysed heel, and the patient is asked to elevate the paralysed leg. In organic paresis the examiner feels a downward pressure under the non-paralysed heel; in malingering no pressure is felt. However,

some have used it in a less precise context as a sign of pain or weakness in the back or lower extremities.² The reliability has been questioned in one study because of poor pelvic stabilisation and varying levels of pain, effort, and spasticity.³

Charles Franklin Hoover (1865–1927) was an American physician born in Cleveland, Ohio, who read medicine at Harvard. He worked in Vienna under Neusser, and in Strasburg with F Kraus before returning to Cleveland. He was appointed Professor of Medicine in 1907. His main interests were in diseases of the diaphragm, lungs, and liver.

Another Hoover’s sign is inward movement of the lower rib cage during inspiration, implying a flat, but functioning, diaphragm.