Abstract
Clinodactyly is defined as an angulation of a digit in the radio-ulnar plane. This anomaly can be congenital, dominantly inherited, or acquired due to trauma or inflammation. Although the deformity usually causes little functional impairment, correction is made because of cosmetic problems. Male subject, with polydactyly on thumb(Wassel's type VII) received first surgery at the age of one. And at the age of six, abnormal growth on the radial side of the first metacarpal bone and ulnar deviation of the distal phalanx of the thumb at the interphalangeal joint had developed. The authors used the growing bony segment from the first metacarpal bone as a bone graft for the correction of clinodactyly on thumb. Z-plasty incision was made on the concave(ulnar) side of thumb and a wedge osteotomy was made on the distal phalanx. The bone graft was inserted into the gap of the distal phalanx of the thumb and fixed it with K-wires. Deformity of the metacarpal bone and clinodactyly on thumb was corrected effectively without donor site morbidity with noticible growth of the grafted metacarpal bone 12 months after surgery.