Application of venous flow-through free flap for multi-finger revascularization and soft tissue defect coverage: a mid-term follow-up

To investigate the treatment outcome of applying venous flow-through free flap for multi-finger injuries with revascularization and soft tissue defect coverage. Between January 2021 and May 2025, 22 cases (51 fingers) with soft tissue defect and vascular defect were treated with venous flow-through flaps. There were 14 males and 8 females, aged 22–50 years (mean, 35years). There included 15 cases of two-finger defects and seven cases of three-finger defects. Functional evaluation were assessed including sensory recovery (S-2PD Test), range of motion (TAM score), and time to return to daily function or work. Mean follow-up was 11 months (range 8 months to 16 months). The size of defects ranged from 1.2 cm ×1.6 cm to 2.0 cm × 3.2 cm, and the size of flaps ranged from 1.5 cm ×1.8 cm to 2.7 cm × 4.0 cm. Eight cases had some degree of swelling, and blistering at the margin of the flap was observed in two patients. All the flaps and donor sites healed completely. All of the flaps recovered protective sensation with the score of 2-PD 15.78 ± 1.30 mm. Using the contralateral finger as a control, the affected finger showed a mean TAM ratio of 82.55% ± 6.35%. 48 fingers were classified as good, and three fingers were classified as fair. The average time to return to daily function or work was 3.64 ± 0.90 months. Venous flow-through free flap can repair both vascular defect and soft tissue defect for complex multi-finger injuries. The flap is thin, flexible, with easily identifiable vascular distribution, and no arterial sacrifice, with low donor site morbidity.