Short 4th and 5th Metacarpals

Also called the metacarpal sign, shortening of the 4th and 5th metacarpals is present when a line drawn at a tangent to their heads intersects the 3rd metacarpal. The commonest causes are
idiopathic, post-traumatic, Turner’s syndrome, pseudohypoparathyroidism, pseudopseudohypoparathyroidism and basal cell naevus syndrome. In this case an old fracture of the 5th metacarpal suggests the cause may be previous trauma.
Reference:
1. Dahnert W. Radiology Review Manual, 5th edition. Lippincott, Williams and Wilkins 2003
2. Weissleder R. et al Primer of Diagnostic Imaging, 3rd edition, Mosby 2003
Credit: Dr Donna D'Souza
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