Hoover's Test Revisited.

Abstract

Hoover's test (Hoover's sign) is a widely recognized sign for diagnosing functional weakness of the lower limb. However, its utility may not have received a fair evaluation. This article highlights several points related to the test. First, it is composed of two subtests: elevation of the normal leg and that of the paretic leg. Both have diagnostic value, but only the former is often mentioned. Second, the popular method of evaluating the pressure felt by the examiner's hand has a limitation. I here propose a new modified maneuver exerting downward force to the lifted leg as well as upward force to the unlifted leg, and then observing the presence or absence of movement in the unlifted leg. This corresponds to the break test in manual muscle testing and is more objective than subjective evaluation of the pressure. Maneuvers that include voluntary downward pressing of the unlifted leg just prior to the main test are not ideal since these will direct the attention of the patient toward the unlifted leg. Third, a new theory of the underlying mechanism of Hoover's test based on synergistic movements is presented. Fourth, the clinical utility of the test and its various methods is discussed considering the purposes of the test. The original method in the supine position is suited to the diagnostic purpose. Some authors have stated that Hoover's test often gives inconclusive results and lacks reliability. However, this test is expected to be sufficiently reliable if the new method is employed.