Hoover's sign for the diagnosis of functional weakness: A prospective unblinded cohort study in patients with suspected stroke

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Abstract

Objective

Hoover's sign – weakness of voluntary hip extension with normal involuntary hip extension during contralateral hip flexion against resistance – is a commonly used sign in the diagnosis of functional weakness of the lower limb. However, little is known about the performance of this sign in clinical practice.

Methods

Hoover's sign was tested as part of the diagnostic work-up of 337 patients presenting to hospital with suspected stroke. We made a gold-standard diagnosis of stroke, functional disorder, or other diagnosis based on clinical history and examination, imaging and clinical follow-up. We calculated the sensitivity, specificity, positive and negative predictive values of Hoover's sign for a diagnosis of functional weakness in patients who presented with leg weakness.

Results

We consecutively recruited 337 consecutive patients with suspected stroke, 124 of whom presented with leg weakness. 8 of these patients had a diagnosis of functional disorder. The sensitivity of Hoover's sign for a diagnosis of functional weakness in those who presented with leg weakness was 63% (95% CI: 24 to 91), and the specificity was 100% (95% CI: 97 to 100).

Conclusions

In this cohort, Hoover's sign was moderately sensitive and very specific for a diagnosis of functional weakness. Further studies are required to assess inter-observer variability and performance of the test in larger numbers of patients with functional weakness.

Introduction

In 1908 Charles Hoover described a physical sign of functional (i.e. psychogenic) weakness of the lower extremities [1]. Hoover's sign is commonly used as a test for the diagnosis of functional weakness. However, no studies have tested the diagnostic performance of this sign in unselected patients with neurological symptoms.[2], [3], [4]. In the next revision of DSM, reference to positive physical signs of functional weakness may be incorporated within the criteria for conversion disorder itself [5]. Data on the specificity and sensitivity of Hoover's sign are therefore important.

In this study, we aimed to determine the sensitivity and specificity of Hoover's sign for the presence of functional weakness in patients who presented with suspected stroke and leg weakness.

Section snippets

Method

We recruited patients presenting to the emergency department of the Western General Hospital, Edinburgh, UK, in whom a nurse or doctor suspected stroke, into a study examining clinical and biochemical diagnostic methods in acute stroke [6]. The study was approved by a research ethics committee and written informed consent obtained from participants. A senior neurology trainee (WW) took a history from each patient, performed a physical examination, and recorded results using a standard research

Results

Hoover's sign was tested in 337 consecutive patients with suspected stroke between July 2007 and February 2009 of whom 124 had leg weakness (Table 1, Fig. 1). 11/337 (3%) of the patients had a diagnosis of a functional disorder and 239/337 (71%) had a diagnosis of stroke. 87/337 (26%) had other non-stroke diagnoses: migraine (14), seizure (11), sepsis (11), peripheral nerve disorder (8), syncope (7), vestibulopathy (6), metabolic disorders (5), musculoskeletal disorders (3), brain tumour (3),

Discussion

In our cohort of patients with suspected stroke, Hoover's sign was a very specific and moderately sensitive test for the diagnosis of a functional disorder in patients with unilateral leg weakness. Functional/ psychogenic weakness accounts for around 10% of 'stroke mimics' in studies of suspected stroke/transient ischaemic attack [8] and 20% among patients without ischaemic stroke who were treated with intravenous thrombolysis [9].

Our study has a number of limitations. The examining neurologist

Acknowledgments

This study was funded by the Chief Scientist's Office of the Scottish Government. Dr. Whiteley was supported the Chief Scientist's Office (CAF/06/30) and is now funded by a Clinician Scientist Fellowship from the UK Medical Research Council (G0902303).

References (10)

  • CF Hoover

    A new sign for the detection of malingering and functional paresis of the lower extremities

    JAMA

    (1908)
  • J Stone et al.

    Hoover's Sign

    Pract Neurol

    (2001)
  • I Ziv et al.

    Diagnosis of ‘non-organic’ limb paresis by a novel objective motor assessment: the quantitative Hoover's test

    J Neurol

    (1998)
  • G Diukova et al.

    Simple quantitative analysis of the Hoover's test in patients with psychogenic and organic paresis

    J Neurol Sci

    (2001)
  • J Stone, WC LaFrance, R Brown, D Spiegel, JL Levenson, M Sharpe. Conversion Disorder: Current problems and potential...
There are more references available in the full text version of this article.

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