Review

The Hoover's Sign of Pulmonary Disease: Molecular Basis and Clinical Relevance

Chambless R Johnston III¹ , Narayanaswamy Krishnaswamy¹ and Guha Krishnaswamy^1,2

¹Department of Internal Medicine, Quillen College of Medicine and James. H. Quillen VA Medical Center, Johnson City, TN 37614-0622, USA

²Department of Medicine, Division of Allergy and Clinical Immunology, James. H. Quillen VA Medical Center, Mountain Home, TN 37684, USA

author email corresponding author email

Clinical and Molecular Allergy 2008, 6:8doi:10.1186/1476-7961-6-8

Published:	5 September 2008

Abstract

In the 1920's, Hoover described a sign that could be considered a marker of severe airway obstruction. While readily recognizable at the bedside, it may easily be missed on a cursory physical examination. Hoover's sign refers to the inspiratory retraction of the lower intercostal spaces that occurs with obstructive airway disease. It results from alteration in dynamics of diaphragmatic contraction due to hyperinflation, resulting in traction on the rib margins by the flattened diaphragm. The sign is reported to have a sensitivity of 58% and specificity of 86% for detection of airway obstruction. Seen in up to 70% of patients with severe obstruction, this sign is associated with a patient's body mass index, severity of dyspnea and frequency of exacerbations. Hence the presence of the Hoover's sign may provide valuable prognostic information in patients with airway obstruction, and can serve to complement other clinical or functional tests. We present a clinical and molecular review of the Hoover's sign and explain how it could be utilized in the bedside and emergent management of airway disease.