Clubbing – Signs and Causes
It is caused by connective tissue proliferation leading to increase in the soft tissue at the base of the nails.Pathogenesis is unclear, may be neurogenic or hormonal. There is an increased blood flow through the fingers. Vagotomy can abolish clubbing.
Signs of clubbing:
- Increased sponginess of the nail bed with increase in the angle between it and the nail usually more than 180°
- Increased curvature of nails in both longitudinal and lateral axes (beaking)
- Increased bulk of soft tissues over the terminal phalanges giving a drum-stick appearance
- Hypertrophic pulmonary osteoarthropathy: pain and swelling over the beds of the long bones above the wrists and ankles symmetrically due to subperiosteal new bone formation. It is usually associated with squamous cell carcinoma of the lungs.
Causes of clubbing:
- infective endocarditis
- cyanotic congenital heart diseases
- Bronchial carcinoma
- Fibrosing alveolitis
- Lung abscess
- Ulcerative colitis
- Crohn’s disease
- Liver cirrhosis