I report a 4-year-old boy with congenital absence of the terminal parts of the distal phalanges of each thumb (Figure 1). The parent had noted the abnormality, but no symptoms such as pain and no functional deficit. On examination the thumbs were short and relatively small. The nails were absent (Figure 2). The thumb-index finger web spaces were normal. There was no palpable nodule at the base of the metacar-pophalangeal (MP) joints. He was unable to extend the interphalangeal (IP joints of the thumbs. The right IP joint was fixed in a position of 90° flexion. The left IP joint was fixed in 30° flexion. The right MP joint was normal with full active extension and flexion. The left MP joint was stable but in a hyperextended position. There was full active flexion. The thumbs could be opposed with all the fingers. The child was otherwise normal. There were no lower limb and no mental abnormalities.
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