Delta phalanx

The authors present a case of congenital, bilateral, symmetrical, and purely transverse plane, abductus deformity of the second digit. The deformity appears to be familial in nature, although other possible etiologies remain including premature closure of the distal-lateral epiphysis of the middle phalanx, or a C-shaped epiphysis of the middle phalanx. The authors review a similar deformity described in orthopedic literature known as a delta phalanx.