Hoover’s sign of

leg A leg is a weight-bearing and locomotive anatomical structure, usually having a columnar shape. During locomotion, legs function as "extensible struts". The combination of movements at all joints can be modeled as a single, linear element cap ...

paresis In medicine, paresis (), compound word from Greek , (πᾰρᾰ- “beside” + ἵημι “let go, release”), is a condition typified by a weakness of voluntary movement, or by partial loss of voluntary movement or by impaired movement. Whe ...

is one of two signs named for Charles Franklin Hoover. It is a maneuver aimed to separate organic from non-organic

of the leg. The sign relies on the principle of synergistic contraction.

Description

Involuntary extension of the "normal" leg occurs when flexing the contralateral leg against resistance. To perform the test, the examiner should hold one hand under the heel of the "normal" limb and ask the patient to flex the contralateral hip against resistance (while the patient is

supine In grammar, a supine is a form of verbal noun used in some languages. The term is most often used for Latin, where it is one of the four principal parts of a verb. The word refers to a position of lying on one's back (as opposed to ' prone', l ...

), asking the patient to keep the weak leg straight while raising it.

Interpretation

If the patient is making an honest effort, the examiner should feel the "normal" limb's heel extending (pushing down) against his or her hand as the patient tries to flex (raise) the "weak" leg's hip. Feeling this would indicate an organic cause of the paresis. If the examiner does not feel the "normal" leg's heel pushing down as the patient flexes the hip of the "weak" limb, then this suggests functional weakness (sometimes called "conversion disorder"), i.e. that effort is not being transmitted to either leg. Alternatively, if a patient reports weakness of hip extension, and appears to have weakness upon direct testing of hip extension, Hoover's test can also be applied. If an examiner places one hand behind the heel of the patient's weak leg and asks her or him to push against it, no movement will be felt. If the patient is asked to raise the other leg (i.e. flexion at the contra-lateral hip), the examiner will feel pressure on his or her hand as the patient involuntarily extends the weak hip. This can be pointed out to the patient in a non-confrontational manner, to help persuade the patient of the functional nature of the weakness. In the context of a positive Hoover's sign, functional weakness (or "conversion disorder") is much more likely than malingering or

factitious disorder A factitious disorder is a mental disorder in which a person, ''without'' a malingering motive, acts as if they have an illness by deliberately producing, feigning, or exaggerating symptoms, purely to attain (for themselves or for another) a p ...

. Strong hip muscles can make the test difficult to interpret. Efforts have been made to use the theory behind the sign to report a quantitative result.

References

{{Eponymous medical signs for nervous system Physical examination Symptoms and signs: Nervous system

Description

Interpretation

See also

References