Finger clubbing is an important medical condition associated with various diseases. Several studies and researches have stated that it is most commonly seen and described as the condition where there is an evident enlargement of the fingers specifically the terminal segments of the digits (fingers or toes). This condition exists due to the production or overproliferation of the connective tissues in the middle of the matrix of the nail and the distal phalanx (Myers & Farquhar, 2001, pp. 341).
The pathophysiology of finger clubbing has been studied by numerous scientists and health experts through the years. However, the formulation of a theory that can be applied to all of the circumstances associated with the condition has not been accomplished yet. Researchers and health professionals identified some of the possible causes of the clubbing of the fingers which include genetic predisposition, neural mechanisms which are mediated vagally, and the effects of tissue hypoxia (Sarkar, Mahesh, & Madabhavi, 2012, pp. 354)
On the other hand, other studies have proposed other causes for the occurrence of finger clubbing. It has been hypothesized that finger clubbing may have been associated with the anastamoses of the local arteriovenous. The anastomoses was observed to be caused by vascular dynamics alterations which resulted to the blood bypassing the capillaries. Additionally, the local arteriovenous anastomoses allow microcirculation of the digits with the help of the autonomic nervous system (Spicknall, Zirwas, & English, 2005, 354).
Finger clubbing is commonly used by health professionals to note and describe changes observed in the shape of fingers and even fingernails. This symptom has been observed to occur in different stages. During the first or initial stage, the sofetening of the nail bed has been observed. Then, in the second stage, there is an observed curving of the nails called “Scarmouth’s Sign”. Then, there will be an increase in the depth of the distal phalanx along with the distal inter-phalangeal joint being hyper-extensible. During the last stage, the clubbed appearance of the finger will already be visible. Lastly, the nail will develop longitudinal ridging while the skin and nail appear shiny (Sarkar, Mahesh, & Madabhavi, 2012, 354; Cancer Research UK, n.d.)
Some of the morphologic findings associated with finger clubbing include existence of fibroblasts which have been considered as primitive, elevated or increased values for lymphocytes and eosinophils, and increase in blood vessels’ caliber and number. Aside from these morphologic findings, clubbing of fingers is mostly asymptomatic unless it is linked with the occurrence of other conditions such as hypertrophic osteoarthropathy. The common symptoms of the condition include swelling and painin the periartiular region (Myers & Farquhar, 2001, 341).
When finger clubbing is detected, it is best to contact a health care provider immediately since this symptom is unusual and is associated with various diseases and conditions. Some of the diseases linked and associated with the clubbing of fingers include lung cancer and other heart and lung diseases that usually results to the reduction of the oxygen available in the blood. A number of these heart and lung diseases include congenital heart defects, chronic infections of the lungs (especially among patients with lung abcess and cystic fibrosis), heart chamber and heart valve infections which are commonly caused by microorganisms such as bacteria, virus, and fungi, lung disorders, celiac disease, cirrhosis, Graves disease, hyperthyroidism, dysentery. Other studies have also identified clubbing of fingers as a common symptom in other cancer types such as liver cancer, gastrointestinal cancer, Hodgkin’s lymphoma, and lung cancer (Murray & Schraufnagel, 2010).
Cancer Research UK. n.d. What is finger clubbing?. [online] Available at <http://www.cancerresearchuk.org/about-cancer/cancers-in-general/cancer-questions/what-is-finger-clubbing> [Accessed on 13 Apr 2016]
Murray, J.F. & Schraufnagel, D.E. 2010. History and physical examinations. Murray & Nadel’s Textbook of Respiratory Medicine. 5th ed. Philadelphia, Pa: Saunders Elsevier.
Myers, K.A. & Farquhar, D.R. 2001. Does This Patient Have Clubbing?. JAMA 286(3): 341-347.
Sarkar, M., Mahesh, D.M., & Madabhavi, I. 2012. Digital clubbing. Lung India 29(4): 354-362.
Spicknall, K.E., Zirwas, M.J., & English, J.C. 2005. Clubbing: An update on diagnosis, differential diagnosis, pathophysiology and clinical relevance. Journal of the American Academy of Dermatology 52(6): 1020-1028.