Analysis of surgical results and of residual postoperative deformities in preaxial polydactyly of the hand.

PURPOSE: Polydactyly is the most common congenital anomaly of the hand. It may occur as a separate event or as part of a syndrome, with preaxial polydactyly of the hand (or thumb duplication) being the most common among Caucasians. The present study analyzed the surgical results and the residual postoperative deformities of patients with thumb duplication.

METHODS: Thirty-one patients with duplicated thumbs were surgically treated from January 2002 to April 2008 and 19 of them, who had returned during the late postoperative period, were evaluated. Each case was typed according to Wassel's classification into seven types and the most common category was type IV. Removal of radial component was done in 18 patients aged on average 51 months.

RESULTS: Patients and parents were satisfied with both the functional results and the appearance of the reconstructed thumb. In the subjective evaluation of residual deformities, axis deviation and residual prominence were commonly found. There were coherencies in data between both subjective and objective outcomes. The children that had difficulty in holding very small objects in the subjective functional result were the same children with residual deformities in the objective result. Patient's age at surgery and Wassel's type influenced the analysis of residual postoperative deformities. There was statistically significant difference in cases of type VII and in patients operated at more than three years of age. Correlation between type VII and patient's age at time of surgery was found. The children with type VII duplication were operated later.

CONCLUSIONS: For a better result, surgical correction should be performed before three years of age, thus correcting all the changes detected, mainly in type VII, in order to reduce the incidence of residual deformity.

TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.