The evolution and refinements of the distally based dorsal metacarpal artery (DMCA) flaps

Anatomy, evolution, and clinical aspects of the superextended-intercompartmental-supraretinacular artery perforator flap (SISAP-flap): A proof of concept

BACKGROUND

Extended soft tissue defects of the fingers-irrespective of their origin-are challenging to treat. In cases of missing amputates or crush injuries, the options are often limited to further amputation, ray resection, or free tissue transplantation. The SISAP-flap was developed to add an extra option to treat finger avulsion injuries or otherwise extended soft tissue finger defects.

METHODS

Cadaveric SISAP-flaps were individually dissected, tested for arterial perfusion using red ink and radiopaque dye, and transposed into artificially created same-size defects. After introducing this flap in the clinic, which was partially successful in the first patient, we modified the flap to its definite design.

RESULTS

Average cadaver flap size ranges between 11 cm and 22 cm in length, allowing dorsal wrapping of the flap over the fingertip and way back to the palmar metacarpophalangeal-joint. The flap is based on the distal web space perforator, which is commonly used by a dorsal metacarpal artery flap and supercharged using an intercompartmental, supraretinacular artery. Donor sites were closed primarily with little tension. Application of the flap in the clinic resulted in satisfactory functional and esthetic outcomes.

CONCLUSION

The SISAP-flap is a new option for the reconstruction of extended finger defects and should be added to the reconstructive surgeon's armamentarium of pedicled flaps, providing relatively short operating times and promising clinical outcomes.

Reconstruction of finger contracture with an expanded first dorsal metacarpal artery perforator flap: A case report

Volar finger contractures can be challenging for plastic surgeons. The dorsal metacarpal artery perforator (DMCAP) flap is frequently used to cover bones, tendons, and neurovascular structures in the dorsum of the hand after trauma and burns as an alternative to grafts and free flaps. We aimed to report volar finger defect reconstruction with expanded DMCAP flap. A 9-year-old male patient applied to our clinic with the complaint of inability to open the second finger of the left hand after an electrical burn that caused proximal and distal interphalangeal joints flexion contractures. Reconstruction was planned for the patient with a two-session expanded first DMCAP flap. A 16 mL 5 × 3 cm tissue expander was placed in the prepared area from the vertical incision in the first session. The tissue expander was inflated with 4 mL of isotonic solution. The DMCA area was enlarged 6 weeks later by giving 22 mL of isotonic solution. After the pedicle dissection, the 9 × 3 cm DMCAP flap was elevated by dissection over the paratenon. With 180° of rotation, the left-hand second finger was adapted to the 6 × 2 cm defect area on the volar face. The flap donor site was closed primarily. The operation was terminated by placing the hand on a protective splint. There were no complications in the flap in the postoperative 6 months. The patient was referred to the physical therapy and rehabilitation department. As a result, an expanded DMCAP flap may cover volar tissue defects up to the distal phalanx. This report may present the first case in which volar finger contracture reconstruction was performed with an expanded first DMCAP flap after an electrical burn in a pediatric patient.

Applications and Reliability of Dorsal Metacarpal Artery Perforator Flap

Dorsal metacarpal artery perforator flap (DMAP), first described by Quaba and Davison, is a useful tool in the armamentarium of plastic surgeons. It provides like for like tissue for the reconstruction of dorsal finger defects. It is a simple and relatively easy flap to harvest with minimal donor site morbidity. In this case series, we present our experience, applications, and surgical technique of flap harvesting.

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.

Functional and aesthetic reconstruction of a dorsal digital skin defect with a sensory neurotized DMCA III flap

The dorsal metacarpal artery (DMCA) flap is an elegant way to reconstruct tissue defects. We present a 25-year-old female patient with a dorsal injury on the fourth digit, which was reconstructed with a third webspace DMCA flap which was neurorrhaphied with a branch of the ulnar nerve, to regain sensation.

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.

Anatomical basis and clinical application of the dorsal perforator flap based on the palmar artery in the first web

PURPOSE

Soft-tissue defects of the thumb and index finger remain a challenge for plastic surgeons. Our purpose was to observe the morphological characteristics of the cutaneous vessels in the first web, to design a dorsal perforator flap based on the palmar artery in the first web and to propose its clinical application.

METHODS

Thirty preserved hand specimens were dissected to observe the origin, course, branch and anastomosis of the dorsal perforators in the first web, and the dorsal perforator flap based on the palmar artery in the first web was designed. Clinically, seven cases of hand defects were reconstructed using this flap.

RESULTS

The blood supply for the dorsum of the first web comprised the dorsal perforators from both the dorsal artery (the branch of the first dorsal metacarpal artery) and palmar artery (the radial palmar digital artery of the index finger and the ulnar palmar digital artery of the thumb). The first dorsal metacarpal artery constantly arose from the radial artery and was divided into the radial, ulnar and medial branches. The palmar artery sent out 1-2 perforators and formed a constant anastomosis with the medial branch of the first dorsal metacarpal artery to supply the dorsal skin of the first web. In clinical application, all the flaps survived completely without contracture of the first web or other complications and the donor regions all healed at the first stage.

CONCLUSION

The dorsal perforator flap based on the palmar artery in the first web is useful to repair soft-tissue defects of the thumb, the proximal phalanx of the index finger and thenar region, leading to a satisfactory appearance and good functional and sensory recovery.

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

Background:

The finger skin and soft-tissue defects are reconstructive challenges due to their nature and the intricate extensor apparatus and flexors it protects. The reverse dorsal metacarpal artery (RDMA) is a time-tested option for the reconstruction of the same.

Materials and Methods:

A total of 14 cases of RDMA flap for finger defects involving proximal to distal phalanx were performed. Thirteen of these patients were male and one patient female and the most common mode of injury was occupational in nature followed by road traffic accident. The overall appearance was assessed for the flap and the donor site. The associated injuries and the range of motion were noted.

Results:

All but one flap survived completely. One patient had partial distal flap loss, which was tackled with split-thickness skin grafting. The flap size varied from 3.5 cm × 1.5 cm to 9 cm × 2 cm with mean of 6.64 cm × 1.72 cm. The mean age of the patients was 33.4 years. All the patients had acceptable aesthesis. The donor site had no complications and healed with linear scar.

Conclusions:

RDMA flap is a reliable flap for finger defects reconstruction. The range of movement mainly depends on the associated injury rather than flap transfer alone and to prove this we require doing analysis of range of movement in patients with flap done alone or with associated injuries.

My 40-year perspective on hand surgery

The author presents his transition of his preferred methods for managing acute trauma and degenerative and congenital conditions of the hand. Based on his career-long experience, he discusses conceptual evolution and current status of treatment of Dupuytren's disease and several congenital anomalies of the hand.

The double-pedicled dorsal-metacarpal-artery (dpDMCA) flap of the hand: a novel DMCA-derived flap

The dorsal-metacarpal-artery (DMCA) flap in its standard or extended version is considered as the working horse to cover dorsal soft tissue finger defects with exposed extensor tendon or bone. We hereby present a clinical case of an 80-year-old male patient who is right-handed and sustained a soft tissue defect of the proximal dorsal aspect of his left 5th finger and the postoperative outcome employing a modified transposition flap. The double-pedicled DMCA flap (dpDMCA flap) of the hand poses in adequate clinical scenarios a comparably fast and safe solution to cover dorsal finger defects extending just distal to the PIP joint. To the best of our knowledge, this is the first report of a DMCA-based flap with a double pedicle to cover soft tissue defects at the dorsum of the hand.

Level of Evidence: Level V, therapeutic study.

Reconstruction of the Adult and Pediatric Burned Hand

Thermal injuries of the hand can have a great impact on function. Initial treatment should focus on the prevention of contracture through the use of tissue-sparing techniques and optimized occupational therapy. Surgical intervention should follow the standard reconstructive ladder and can involve several techniques from simple to complex including minimally invasive techniques, such as laser and steroid injection, contracture release and skin grafting, and local tissue rearrangement and regional flaps as well as distant pedicled and free flaps. Reconstructive surgery of the hand, when performed well, can lead to meaningful functional improvement in severe burns.

Extended distally based DMCA flap in combination with autologous amputate skin transplantation as a salvage procedure for ring avulsion injury

A 23-year-old male student presented to our clinic with a traumatic complex ring avulsion of his right dominant index finger. Clinical evaluation revealed a complete distal amputation of the DIP joint with a laceration of the soft tissue at the middle phalanx and a rupture of the FDP-2-tendon far proximally. We hereby present the patient’s clinical outcome after reconstruction with a distally based extended DMCA-II flap. To our own knowledge, this is the first report of an extended distally based DMCA flap for coverage of a class IVd ring avulsion injury in combination with autologous amputate skin transplantation.

Level of Evidence: Level V, therapeutic study.

Enhancing aesthetic outcomes of soft-tissue coverage of the hand

Hand aesthetics in general and aesthetic refinements of soft-tissue coverage of the hand in particular have been increasingly considered over the past few years. Advancements of microsurgery together with the traditional methods of tissue transfer have expanded the number of techniques available to the reconstructive surgeon, thus shifting the reconstructive paradigm from simply "filling the defect" to reconstructive refinement to provide the best functional and aesthetic results. However, drawing the boundary between what does and what does not constitute "aesthetic" reconstruction of the hand is not straightforward. The selection among the vast amount of currently available reconstructive methods and the difficulties in objectively measuring or quantifying aesthetics have made this task complex and rather arbitrary. In this article, the authors divide the hand into several units and subunits to simplify the understanding of the basic functional and aesthetic requirements of these regions that may ultimately bring order to complexity.

Local and regional flaps for hand coverage

Hand surgeons are frequently challenged by the unique requirements of soft tissue coverage of the hand. Whereas many smaller soft tissue defects without involvement of deep structures are amenable to healing by secondary intention or skin grafting, larger lesions and those with exposed tendon, bone, or joint often require vascularized coverage that allows rapid healing without wound contraction. The purpose of this review was to present an overview of local and regional flaps commonly used for soft tissue reconstruction within the hand.

Local flaps of the hand

A local flap consists of skin and subcutaneous tissue that is harvested from a site near a given defect while maintaining its intrinsic blood supply. Local skin flaps can be a used as a reliable source of soft tissue replacement that replaces like with like. Flaps are categorized based on composition, method of transfer, flap design, and blood supply, but flap circulation is considered the most critical factor for the flap survival. This article reviews the classification of local skin flaps of the hand and offers a practical reconstructive approach for several soft tissue defects of the hand and digits.

Open fractures of the hand with soft tissue loss

The evaluation, initial treatment, and definitive reconstruction of open fractures of the hand with associated soft tissue loss are reviewed. Specific attention is given to the literature on open fracture antibiotic prophylaxis in the hand; the timing of bone and soft tissue reconstruction; and options for soft tissue coverage, including local, regional, and distant tissue transfer. Factors that have shown association with outcomes in these injuries are also discussed, and the authors' preferred management is summarized.

Free iliac flap for treating multiple skin defects of the hand and digits

A total of eight cases with multiple skin defects of the hand and digits were resurfaced using a free iliac flap. The lesions involved both the hand and multiple digits in five patients and multiple digits in three patients. The average skin flap size was 89.3 cm(2). In three, a piece of of vascularized iliac bone was included. There was no flap loss. Flap debulking was performed in five patients at 10-12 weeks post-surgery during the operation for flap separation and inset. Secondary flap debulking was performed in one patient at 6 months post-surgery. The average static 2-point discrimination was 15.4 mm in five patients, whereas the remaining patients only exhibited sensation to pressure. This procedure may require additional refinement; however, the free iliac flap with technical refinements is a viable option for the treatment of multiple skin defects of the hand and digits.

Thumb reconstruction

Thumb reconstruction aims to restore the cardinal thumb traits and actions including mobility, stability, sensibility, length, and appearance. The level of thumb loss is divided into thirds: distal (tip to interphalangeal [IP] joint), middle (IP joint to metacarpal neck), and proximal (metacarpal neck to carpometacarpal joint). Distal third reconstruction usually requires only soft tissue restoration. Many options exist for middle third reconstruction, including increasing thumb ray length (metacarpal lengthening, osteoplastic reconstruction, toe transfer) and increasing relative length (phalangization). Proximal third reconstruction is best accomplished with toe transfer, pollicization, or on-top plasty (pollicization of a damaged index finger).

Recurrent interdigital pilonidal sinus treated with dorsal metacarpal artery perforator flap

A 39-year-old otherwise healthy barber presented to our clinic complaining of frequent periods of swelling and purulent discharge in his second and third right web spaces. An excision was performed after administration of methylene blue to visualize the extent of both cysts located in his second and third web spaces. A distally based dorsal metacarpal artery perforator flap was chosen to close the defect on his second web space. Interdigital pilonidal sinus is a rare disease caused by repeated implantation of foreign hair to the interdigital web space. In secondary cases or in cases where an extensive resection has to be done in order to completely remove the cysts, closure with a skin flap can become compulsory. Dorsal metacarpal artery perforator flap is a good choice with minimal donor site morbidity and this flap might provide robust skin coverage which can possibly avoid further penetration of hair in to web space.

The use of reverse-flow dorsal metacarpal artery flaps after postburn metacarpophalangeal joint flexion contracture release

When thermal injuries of the hand are managed inappropriately, complex hand contractures are inevitable. Patients with hand contractures may have many difficulties in their daily life because of this deformity. These patients are challenging to reconstructive surgeons. In this study we evaluated reverse-flow dorsal metacarpal artery flaps for the defects occurred after metacarpophalangeal joint contracture release of different fingers. Nineteen patients with defects on the volar surface of metacarpophalangeal joint were reconstructed by the reverse-flow dorsal metacarpal artery flaps. All operations were successful and flap losses were not seen. The DMCA flaps provide one stage coverage and permit primary closure of the recipient site. The aesthetic and functional results are satisfactory without sacrificing main arteries. The only drawback is the residual scar on the dorsum of the hand, which can be treated by conservative means and may improve over time.

Soft tissue reconstruction of the hand

There are a number of insults that can compromise the soft tissue envelope of the hand. Soft tissue reconstruction seeks to restore both the aesthetic appearance and the function of the hand. The purpose of this review is to describe recent advances in hand soft tissue reconstruction. Skin grafts and skin substitutes both are useful reconstructive options for certain defects. Digital coverage continues to be subject to refinements that lead to better reconstructions. Flaps based on donor sites from the dorsal metacarpal artery system are finding continually expanding uses in hand reconstruction. Traditional notions of forearm-based donor tissue are being challenged, leading to better hand reconstructions with less donor morbidity. Finally, improvements in free tissue transfer enable the expansion of reconstructive possibilities available for hand coverage.

Free 'mini' groin flap for digital resurfacing

Ten cases of post-traumatic skin and soft tissue loss over the digits were resurfaced by free 'mini' groin flap. Five patients had defects of the dorsum of the digit, three had proximal palmar defects, one patient had circumferential skin loss and one had multiple digital injuries. The flap was harvested from the contralateral groin using a two-team approach. The average size of the flap was 5.5 x 4.75 cm and the mean operating time was 2.45 hrs. All patients had physiotherapy within 48-72 hrs. There were no flap losses. Six patients were happy with the cosmetic result and did not require any further debulking. We recommend free tissue transfer for digital resurfacing specifically in moderate to large dorsal defects, proximal volar defects, circumferential skin loss and multiple digit injuries.

Anatomical study of the palmar intermetacarpal perforator flap

The authors present an anatomical study of a small flap that may be harvested from any of the palmar intermetacarpal spaces while performing fasciectomy in Dupuytren's contracture. The flap is diamond-shaped, vascularised by two perforating branches originating from the underlying true digital arteries and may be rotated through 90 degrees to 180 degrees in either direction to provide skin cover and subcutaneous padding over the distal palm and/or the base of the finger.