10Schamroth signWhen the distal phalanges (bones nearest the fingertips) of corresponding fingers of opposite hands are directly opposed (place fingernails of same finger on opposite hands against each other, nail to nail), a small diamond-shaped "window" is normally apparent between the nailbeds. If this window is obliterated, the test is positive and clubbing is present.Dr. Schamroth demonstrated it first in his own finger
23Secondary form of clubbing Secondary form of clubbing is mostly secondary to systemic illness affecting mainly respiratory system, cardiovascular system, hepatobiliary system and gastrointestinal system, and hence is bilateral in general.
24Respiratory system diseases associated with clubbing Neoplastic:Bronchial adenomaMesotheliomaBronchogenic carcinoma(common in adults)Suppurative:BronchiectasisLung abscessEmpyemaPulmonary TB
25Cardiovascular diseases Cyanotic congenital heart diseases: Tetralogy of FallotTransposition of Great Cardiac vesselsVentricular Septal DefectsEbstein anomalyBacterial endocarditisAtrial myxomasChronic congestive heart failure
30Differential clubbing It refers to clubbing with cyanosis limited to either upper or lower limbs.Clubbing with cyanosis limited to lower limb is seen in Patent Ductus Arteriosus with a reversed shuntClubbing with cyanosis limited to upper limb is seen in Transposition of great vessels with PDA with reverse shunt.
31PseudoclubbingAs the name suggests, it refers to appearance of clubbing without actual presence of it, seen in:Hyperparathyroidism: there is excessive resorption of distal phalangesHansen’s diseaseLeukemia: bone destruction due to secondary deposits