The reverse dorsal metacarpal artery flap in finger reconstruction: A reliable choice

Clinical application of an expanded reverse-island flap with two dorsal metacarpal arteries and dorsal metacarpal nerves in index- and middle-finger-degloving injury repair and amputation reconstruction

The dorsal metacarpal artery flap (DMAF) is irrefutable as an effective way of repairing long finger defects, and hand surgeons might consider using it for long finger reconstruction or degloved injury repair. Unfortunately, the DMAF containing a single dorsal metacarpal artery (DMA) hinders the treatment effect. The sensory restoration of long fingers and the reconstruction of phalangeal joints and tendon grafts are unsolved challenges as well. We reported our experience in reconstructing the index and middle finger by a reverse-island flap with two DMAs and dorsal metacarpal nerves (DMNs) with blood supply. We reviewed ten patients with finger-crush injuries affecting eight index fingers and two middle fingers. Degloving injuries occurred in two patients, and finger amputations occurred in eight others. Two patients received simple flap reconstruction, and eight received finger reconstruction, including seven from abandoned phalangeal joints and tendon grafts of the severed finger and one from the iliac crest bone graft. All patients underwent finger reconstruction by an expanded reverse-island flap consisting of two DMAs and DMNs up to a maximal size of 9 × 8 cm². Postoperative follow-up evaluation showed a satisfactory appearance and functional recovery of the reconstructed fingers. We posit that the expanded reverse-island flap involving two DMAs and DMNs constitutes a feasible and safe option for restoring a severely damaged index or middle finger, particularly for patients who are unwilling to undergo toe-to-finger transplantation to reconstruct the injured long fingers.

Finger Reconstruction With Distally Based Dorsal Metacarpal Flaps: A Systematic Review

BACKGROUND

Distally based dorsal metacarpal flaps for the reconstruction of finger soft-tissue defects are classified into 3 categories: dorsal metacarpal artery perforator flap, reverse dorsal metacarpal artery (RDMA) flap, and extended reverse dorsal metacarpal artery (ERDMA) flap. The present systematic review aimed to evaluate differences in the outcomes of commonly encountered defects and postoperative complications among these three flaps.

METHODS

PubMed, Scopus, and Web of Science were systematically searched from when the flats were first reported to May 2021. Random-effects meta-analysis for each outcome was performed, and 24 studies were included in the analysis.

RESULTS

Dorsal metacarpal artery perforator flaps were mainly used for defects extending to the proximal interphalangeal joint (n = 62 [29.1%]) and proximal phalanx (n = 85 [39.9%]). Conversely, defects extending to the distal phalanx (n = 24 [43.6%]) were mostly reconstructed using the ERDMA flap. The rate of venous congestion was highest for the ERDMA flap (29.3%; 95% confidence interval [CI], -17.2% to 65.1%; I2 = 0%) and lowest for RDMA flap (8.1%; 95% CI, -5.9% to 21.7%; I2 = 0%). The RDMA flap showed the lowest rate of any short-term complications, including partial and total necrosis (6.6%; 95% CI, -6.8% to 19.8%; I2 = 0%).

CONCLUSIONS

This systematic review demonstrated that the dorsal metacarpal artery perforator flap was suitable for reconstruction proximal to the middle phalanx, and the ERDMA flap was suitable for reconstruction distal to the distal interphalangeal joint. Although the RDMA flap showed the lowest rate of short-term complications and limited analysis was secondary to limited data available, these occurred in 6.6% to 10.9% of distally based dorsal metacarpal flaps.

[Repairing large skin defect of hand with modified dorsal metacarpal artery reverse island flap]

OBJECTIVE

To investigate the effectiveness of modified dorsal metacarpal artery reverse island flap based on two adjacent recurrent branches of dorsal metacarpal arteries in repairing large skin defect of the hand.

METHODS

Between September 2017 and March 2021, 15 cases of large skin defect of the hand were treated. There were 11 males and 4 females with an average age of 42 years (range, 24-66 years). The injury causes included machine twist injury in 6 cases, pound injury in 5 cases, and crush injury in 4 cases. The injured parts included 6 cases of finger skin defect and 9 cases of distal skin defect of palm and dorsum of hand, all of which had tendon, joint, and bone exposure. The interval from injury to operation ranged from 2 to 6 hours (mean, 4 hours). The defect sizes after thorough debridement ranged from 3.5 cm×3.0 cm to 8.0 cm×4.5 cm. The modified dorsal metacarpal artery reverse island flap with a range of 3.8 cm×3.3 cm to 9.0 cm×5.0 cm was used to repair the defect, and the flap donor site was repaired with full-thickness skin graft.

RESULTS

All the flaps survived successfully after operation, and the wounds in the recipient site and the skin grafts in the donor site healed by first intention. All patients were followed up 9-24 months, with an average of 14 months. The appearance of the flap was good, and its texture and color were similar to those of the surrounding normal tissue. There was no obvious scar contracture, depression, and pigmentation in the donor site. At last follow-up, the static two-point discrimination of the flap was 8-20 mm, with an average of 13.6 mm. According to the Michigan Hand Outcome Questionnaire, 5 patients were very satisfied with the appearance of the flap, and 10 patients were satisfied.

CONCLUSION

The modified dorsal metacarpal artery reverse island flap based on two adjacent recurrent branches of dorsal metacarpal arteries has reliable blood supply, larger harvested area, simple procedure, and minimal donor site damage, which is suitable for emergency repair of large skin defect of the hand.

Use of Heparin Cream for Venous Congestion in the Extended Reverse Metacarpal Artery Flap: A Case Report

Finger dorsum defects are a challenging situation. Many reconstruction methods are used in these defects. Extended reverse dorsal metacarpal artery (RDMA) flap is used in dorsal finger reconstruction. Venous congestion in this flap is most important cause of flap failure. In this case, we presented a case in which we used heparin cream due to development of venous congestion in our patient who underwent an extended RDMA flap. A 24-year-old female patient presented to the emergency department with a defect of dorsal of left-hand fourth finger. Defect was covered with an extended RDMA flap. On postoperative first day, venous congestion was observed, and heparin cream was applied three times a day on flap. The signs of venous congestion were regressed. Tissue healed as a result of superficial epidermolysis and skin grafting. No functional limitation was observed in sixth-month postoperative control. Venous congestion is the most important cause of flap failure of extended RDMA flaps. Generally, subcutaneous heparin administration and leech therapy are used. In our case, heparin was applied as a cream instead of subcutaneously, and flap healing was observed as a result of superficial epidermolysis. Heparin cream application can also be used as a treatment option in flaps with venous congestion.

Multi-dorsal metacarpal artery perforator adipofascial turnover flap for index to little finger reconstruction: Anatomical study and clinical application

Reconstruction of the dorsum of the hand and fingers is one of the main challenges in hand surgery. Regional flaps from the forearm, free flaps, or pocket procedures are options when multiple digits are injured with tendon damage and bone exposure. These procedures can be technically demanding and are often plagued by a texture mismatch. We conducted an anatomical study of 20 fresh frozen hands. The second, third and fourth intermetacarpal spaces were analyzed with the aim of defining the vascular foundation of dorsal hand adipofascial-turnover flaps based on dorsal metacarpal artery (DMA) perforators, analyzing their potential for reconstruction procedures on the dorsum of the hand. In three cases, the 4th intermetacarpal space lacked the DMA. A mean of 3.5 arterial communications were found between the DMA and palmar arterial system. Each hand had 11 ± 2 dorsal skin perforators, which were equally distributed among different intermetacarpal spaces. At least one perforator was present in each one-third of the space. The most distal perforators were the largest in all spaces but missing in two hands. A clinical case of multiple index finger to little finger reconstruction with this new multi-dorsal metacarpal artery perforator (mDMAP) adipofascial turnover flap is presented. Our anatomical study confirmed previous descriptions of the anatomy of the dorsum of the hand. It supports the safety of the mDMAP adipofascial turnover flap based on all distal arterial perforator for the simultaneous reconstruction of index to little finger injuries. Similarly, adipofascial turnover flaps can be raised from more proximal perforators arising from DMAs if more than one intermetacarpal space is included.

Dorsal Metacarpal Artery Flap: An Underrated Workhorse Flap for Reconstruction of Dorsal Finger Defects

The dorsal metacarpal artery (DMCA) flap is a versatile option in the armamentarium of the reconstructive hand surgeon, especially for resurfacing dorsal finger defects where the flap options are limited. The flap fulfills most of the reconstructive principles such as "to replace like with like" and is simple, reliable, and easy to harvest with minimal donor site morbidity. In this report, we discuss the case of a 37-year-old male patient who presented with a partially healed wound over the right middle finger. Several variations of the DMCA flap have been described in the literature, and these are briefly described here along with their applications and vascular basis.