Technical refinement of the reverse homodigital dorsoradial flap: A preliminary case report on flap optimization for radial thumb defects

Soft tissue reconstruction of the radial thumb tip remains surgically challenging, particularly when standard options such as kite or Brünelli flaps are less suitable due to anatomical constraints. This technical note presents the case of a 37-year-old male with a radial-sided distal thumb defect reconstructed using a reverse homodigital dorsoradial flap. Two key refinements were applied: preservation of approximately 5 ​mm of subcutaneous tissue to support venous outflow and a 3–5 ​mm proximal safety margin at the pivot point based on Doppler assessment to reduce pedicle tension during 180° rotation. The flap was inset without tunneling and healed without complications. Functional recovery was confirmed by progressive improvements in the disabilities of the arm, shoulder and hand score (from 25 ​at 1 month to 4.2 ​at 1 year), normal range of motion, and two-point discrimination (from 5 ​mm to 4 ​mm). This case highlights the practical advantages of flap design refinement for radial thumb reconstruction and supports its reproducibility in similar clinical scenarios. However, as this is a single case report, further validation with studies involving multiple cases is necessary to confirm the reliability and broad applicability of these refinements.