A male patient, 48 years old, had a history of grinding injury. The defect size was about 1.5×2.0 cm over the right thumb (Fig. 1). Debridement and coverage by heterodigital island flap surgery was done (Fig. 2). As the name implies, a heterodigital island flap is, applied from the side of a finger. It is a large rectangular flap raised from nearly half of the digital skin without including any distal pulp. The technique is performed using the tourniquet control with the skin strip excision including the digital artery was performed2. The skin flap is elevated to include the underlying adipofascial tissue. After the proximal digital artery is dissected, the elevated skin flap is sutured to the defect of finger using a 5-0 or 6-0 nylon suture. The donor site is then covered by a full thickness skin graft. Donor site was right wrist. After POD 3, donor site was intact without any complications (Fig. 3). Patient had undergone flap detachment at POD 7 (Fig. 4). The patient's hospital day was 10 days after heterodigital island flap surgery.

A well-performed fingertip reconstruction requires preservation of the length of the finger and if possible, provision of a sensate and durable tip for patients activities of daily living (ADL) for the patient3. However, conventional heterodigital island flap reconstruction requires immobilization of the finger joint for approximately two weeks, there by resulting in longer hospital stays4. To overcome these disadvantages, we applied the early flap detachment technique to the patients who had undergone heterodigital island flap surgery. In all cases, all defects were successfully covered by the flap without donor site complications. In the early detachment group, the mean detachment day was 8.5 days compared to 12.38 days in the conventional group. Joint stiffness was observed in 1 patient, and partial flap necrosis in 1 patient was managed by debridement and daily dressing changes in the conventional group. In the early detachment group, 1 patient complained of trigger finger which was resolved by personal trainning exercise. In both groups, dehiscence was observed in 3 patients in each case, but all were resolved by simple primary suturing (Table 2). Hospital day for the flap detachment was 15.8 days in the early detachment group as compared to 19.77 days in the conventional method group. Statistically significant differences were observed between early detachment group and conventional method group (p=0.02) (Table 3).

Hence, heterodigital island flap is a widely used operation methods in fingertip injuries. In general, flap detachment requires stabilization for about 2–3 weeks before resuming the formation of stable vascular supply456. However, previous studies, by using salvage procedure, several authors have studied the timing of the venous channel formation of the flap to overcome congestion7. Also, early division of skin bridge has been noted in the other literatures89. In the cases reviewed in the current study, we designed early detachment methods with skin strip excision that was achieved by the same method used for the formation of stable vascular supply. We expected that early detachment would be effective in decreasing the several complications as compared to conventional detachment especially with regards to minimize the hospital stay. And to prevent any risk of early detachment, we use vascular clamp in proximal and distal skin bridge. After that, confirming the skin color of flap was intact, detachment was performed. And surrounding infection sign was found, the flap was not detached. Taking into consideration all the above aspects, we tried to early detachment at the heterodigital island flap.

In the early detachment group, the hospital day was statistically and significantly decreased compared with the conventional group. Additionally, all patients resumed their ADL earlier.

In addition our study, no severe venous congestion which may influence flap viability was observed in both groups. These results indicate that the formation of neovascularization was occurrs before the flap detachment. This study has clearly indicates that early flap detachment of heterodigital island flap is associated with favorable outcomes in terms of length of hospitalization. Additionally, early detachment results in a shortend period for joint immobilization period. There by directly improving the quality of life of the patient and their return to daily living. Also, we noticed venous channel formation is completed at flap detachment. We expect this technique has the potential to be further researched and developed in the surgical field of fingertip reconstruction.