Clubbing refers to focal swelling of the fingers and toes caused by proliferation of connective tissue between the nail matrix and distal phalanx. It is characterized by increased transverse and anteroposterior diameter of the nails. Clubbing can be examined by measuring angles like the Lovibond angle and hyponychial angle. The degree of clubbing is classified from 10 to 40 based on features present. Common causes of clubbing include cyanotic heart disease, lung diseases like bronchiectasis and cystic fibrosis, gastrointestinal conditions like inflammatory bowel disease, and infections like endocarditis. Clubbing is a nonspecific physical finding that may indicate underlying chronic diseases or conditions.

1. “CLUBBING”
Presenter: Dr **** ******* (EvilDoctor666)

2. CLUBBING
• History
• What is Clubbing?
• Mechanism of clubbing
• Examination and Degree of
Clubbing
• Causes of Clubbing

3. History
• First described by Hippocrates, 2500
years ago, in a patient with
empyema
• Aka “Hippocratic Fingers/Nails”
• Other names: watch-glass nails,
drumstick fingers

4. Definition
Focal bullous swelling of
terminal part of fingers and
toes as well as increased AP
and transverse diameter of
nails due to proliferation of
connective tissue between
nail matrix and distal
phalynx.

5. Pathophysiology
Possible Mechanism:
• Arterial Hypoxemia – Opening of deep AV
anastomotic channel and soft tissue
growth
• Plasma Growth Hormone Level (study
based)
• Megakaryocyte-Platelet theory
(Dickinson & Martin)

6. Examination
Profile Sign/Lovibonds
Angle
• Angle made by nail
as it exits proximal
nail fold
• Normally <180◦

7. Examination
Hyponychial Angle
Normal <192 degrees
Phalangeal Depth Ratio
>1 is indicative of clubbing
Digital index
10.2 or higher is indicative
of clubbing

8. Examination
Shamroth’s Sign or Window Sign

9. Degree of Clubbing
DEGREE FEATURE
1⁰ Clubbing Increased flactuation of nail bed with loss of
onychodermal angle
2⁰ Clubbing Above + Increased AP and transverse diameter as
well as nails becomes smooth and glossy due to
loss of longitudinal ridges
3⁰ Clubbing Above + increased pulp tissue
4⁰ Clubbing Above + features of hypertrophic
Osteoarthropathy

10. Causes (Cardiac)
• Cyanotic congenital heart disease. Eg TOF
• Subacute Bacterial Endocarditis
• Cardiac Tumors (Rarely) (eg. Atrial myxoma)
• Eissenmengers’ syndrome

11. Causes (Lung)
• Bronchiectasis
• Lung abscess
• Bronchogenic Ca.
• Cystic Fibrosis
• Empyema Thoracis
• Fibrosing Alveolitis
• Pleural
Mesothelioma
• Pulmonary AV
Fistula
• Rarely in
fibrocaceous TB.

12. Causes (Gastrointestinal)
• Crohn’s disease
• Ulcerative Colitis
• Coeliac Disease
• Malabsorption Syndrome
• Polyposis Coli
• Billary cirrhosis

13. Causes (Others)
• Endocrinal – eg Thyroid Acropachy,
Hyperparathyroidism
• HIV AIDS
• Genetic
• Idiopathic

14. Causes (of Unilateral
Clubbing)

15. Causes (of UniDIGITAL
Clubbing)
• Hereditary
• Repeated local trauma
• Rarely from median nerve injury or deposition
of tophi (gout)
• Sarcoidosis
• Digital mucoid cyst
• Osteoid Osteoma, enchondroma,
myxochondromas

16. Differential Clubbing
• Selectively occurs in the lower limb, sparing
the upper limb.
• Seen in PDA with shunt reversal

17. References
• Harrison’s Principle of Internal Medicine
• Digital Clubbing – Sarkar et al, Lung India,
2012 (Oct-Dec); 29 (4): 354-362
• Clubbing: An update on diagnosis, differential
diagnosis, pathophysiology, and clinical
relevance – Spicknall et al, J AM ACAD
DERMATOL VOLUME 52, NUMBER 6
THANKS