Thumb and first webspace reconstruction in nonsyndromic congenital mitten hand with symbrachydactyly

Introduction: Nonsyndromic congenital mitten hand with thumb and index finger syndactyly is rare. Reconstruction of this condition is challenging, requiring repositioning of the thumb and creation of a wide and deep first webspace. The aim of this paper is to describe the characteristics of patients with this condition and also to describe our surgical technique.

Methods: We describe our technique in 16 consecutive children utilizing complete mobilization of the first metacarpal and thumb as an island flap on the neurovascular bundle, with a rotational osteotomy to reposition the thumb in pronation. In addition, a dorsal M flap was used to reconstruct the first webspace. Patients in this series also had varying degrees of symbrachydactyly with hypoplastic or aplastic phalanges of the central digits.

Results: There were 9 male and 7 female patients, with a mean age of 24.4 ± 22.4 months at the time of surgery. Mean follow-up was 19.1 ± 18.3 months. All reconstructions healed well. The mean thumb web distance in the affected hands was 4.2 cm (range 3.5 to 5). All reconstructed thumbs had a good opposition. Two children initially had mild hypertrophic scarring, which resolved with pressure gloves. No other complications were observed.

Conclusion: One-stage reconstruction of the thumb and first webspace can be effectively achieved with our technique of complete mobilization of the thumb unit, rotational osteotomy, and a dorsal interdigitating M flap.