Thumb polydactyly with a floating ulnar thumb.

Area of Science:

• Hand Surgery
• Congenital Anomalies
• Plastic Surgery

Background:

• Thumb polydactyly is a common congenital hand anomaly, with the floating type occurring in 0.9-15% of cases.
• A floating ulnar thumb, a specific subtype, is exceptionally rare, with only one prior reported case.

Observation:

• This report presents a unique case of thumb polydactyly exhibiting a floating ulnar thumb.
• The case involved triphalangism and hypoplasia of the thenar muscles.
• Vascular supply to the floating ulnar thumb originated from the superficial palmar arterial arch.

Findings:

• Surgical intervention successfully reconstructed the thumb's morphology.
• Digital nerve transposition from the ulnar to the radial thumb was performed to preserve sensation.
• The case highlights a rare combination of congenital hand anomalies.

Implications:

• This case expands the understanding of rare thumb polydactyly variations.
• The surgical technique offers insights into preserving thumb sensation in complex reconstructions.
• Further research into the embryology and surgical management of such anomalies is warranted.