Correction of a deformed thumb by distraction of the phalanx.

We used distraction osteogenesis to correct six deformed thumbs in four patients ranging in age from 4 to 7 years. Two of the patients had Apert syndrome (syndromic craniosynostosis with symmetrical syndactyly) and two had polydactyly. We used a small fixator with a ball joint and successfully corrected the angular deformity after lengthening the proximal phalanx by distraction. This single inclusive procedure was extremely useful. We found the optimal distraction regimen for the digital phalanx was a one day waiting period and lengthening at 1 mm/day. The mean healing indexes were 37.2 days/cm (range 24.2 to 41.5) in those with Apert syndrome and 64.3 days/cm in those with polydactyly (62.5 and 66.0). Our results suggest that osteogenesis at the distraction site may be quicker in patients with Apert syndrome than in those with polydactyly.