Hoovers Sign (Pulmonary)
Background[edit | edit source]
Hoover's sign (pulmonary) is 1 of 2 signs named for Charles Franklin Hoover, the other being Hoover's sign (paresis)[1]. It refers to paradoxical inward movement of the lower lateral rib cage (costal margin) during inspiration, instead of outward as is normal[2]. COPD, and more specifically emphysema, often lead to hyperinflation of the lungs due to air trapping[2]. Lung hyperinflation causes flattening of the diaphragm, which contracts downwards on inspiration, paradoxically pulling the inferior ribs inwards instead of out[3][4].
Clinical Relevance[edit | edit source]
Some healthy individuals may also exhibit a slight indrawing of the lower lateral ribcage on maximal inspiration, however, patients with COPD exhibit a gross exaggeration of this movement[5]. Hoover's sign may occur at end inspiration or throughout[6]. It occurs both at rest and during exercise[5].
Hoover's sign is best appreciated by placing the first and second fingers on the costal margin near the anterior axillary line.[35] Occasionally, a biphasic Hoover's sign is seen when the costal margin moves out initially, then in, and then moves out again with the onset of expiration.[35] Paradoxical lateral rib cage movement is seen in both upper and lower rib cages, but it is greater at the lower rib cage level. COPD patients may also show inspiratory indrawing of the lower sternum known as anteroposterior ribcage paradox. It occurs typically in early inspiration and usually occurs along with lateral paradox.
The sign is reported to have a sensitivity of 58% and specificity of 86% for detecting obstructive airway disease3 which may make it a useful sign in the diagnosis of COPD. Previous studies have shown a frequency of Hoover’s sign of 36%, 43%, and 76% in Global initiative for chronic Obstructive Lung Disease (GOLD)4 moderate, severe, and very severe stages of COPD, respectively.5
In describing a phenotype of patients with Hoover’s sign, previous studies found that the presence of Hoover’s sign is associated with older age, higher body mass index (BMI), and more severe airflow obstruction. Studies have not shown that Hoover’s sign is associated with a higher degree of hyperinflation.6,7 The presence of Hoover’s sign in individuals with COPD may have important clinical implications because it is associated with higher exacerbation frequency,8 higher dyspnea symptoms with exercise,9 and an increased frequency of hospitalizations and emergency department visits.8
- ↑ Hoover CF. THE DIAGNOSTIC SIGNIFICANCE OF INSPIRATORY MOVEMENTS OF THE COSTAL MARGINS. The American Journal of the Medical Sciences (1827-1924). 1920 May 1;159(5):633.
- ↑ 2.0 2.1 McKenzie DK, Butler JE, Gandevia SC. Respiratory muscle function and activation in chronic obstructive pulmonary disease. Journal of applied physiology. 2009 Aug;107(2):621-9.
- ↑ Gilmartin JJ, Gibson GJ. Abnormalities of chest wall motion in patients with chronic airflow obstruction. Thorax. 1984 Apr 1;39(4):264-71.
- ↑ Hoover CF. THE DIAGNOSTIC SIGNIFICANCE OF INSPIRATORY MOVEMENTS OF THE COSTAL MARGINS. The American Journal of the Medical Sciences (1827-1924). 1920 May 1;159(5):633.
- ↑ 5.0 5.1 Sarkar M, Bhardwaz R, Madabhavi I, Modi M. Physical signs in patients with chronic obstructive pulmonary disease. Lung India. 2019 Jan-Feb;36(1):38-47. doi: 10.4103/lungindia.lungindia_145_18. PMID: 30604704; PMCID: PMC6330798.
- ↑ Maitre B, Similowski T, Derenne JP. Physical examination of the adult patient with respiratory diseases: inspection and palpation. European Respiratory Journal. 1995 Sep 1;8(9):1584-93.
