Free conjoined or chimeric medial sural artery perforator flap for the reconstruction of multiple defects in hand

The Medial Sural Artery Perforator Flap: A Historical Trek from Ignominious to “Workhorse”

Rather than just another “review,” this is intended to be an “overview” of the entire subject of the medial sural artery perforator (MSAP) flap as has been presented in the reconstructive literature from its inception in 2001 until the present, with any exceptions not purposefully overlooked. Unfortunately, the pertinent anatomy of the MSAP flap is always anomalous like most other perforator flaps, and perhaps even more variable. No schematic exists to facilitate the identification of a dominant musculocutaneous perforator about which to design the flap, so some adjunctive technology may be highly valuable for this task. However, if a relatively thin free flap is desirable for a small or moderate sized defect that requires a long pedicle with larger caliber vessels, the MSAP flap deserves consideration. Indeed, for many, this has replaced the radial forearm flap such as for partial tongue reconstruction. Most consider the donor site deformity, even if only a conspicuous scar on the calf, to be a contraindication. Yet certainly if used as a local flap for the knee, popliteal fossa, or proximal leg, or as a free flap for the ipsilateral lower extremity where a significant recipient site deformity already exists, can anyone really object that this is not a legitimate indication? As with any perforator flap, advantages and disadvantages exist, which must be carefully perused before a decision to use the MSAP flap is made. Perhaps not a “workhorse” flap for general use throughout the body, the MSAP flap in general may often be a valuable alternative.

[Research progress of clinical application of medial sural artery perforator flap]

Objective

To review the research progress of the clinical application of the medial sural artery perforator flap (MSAPF).

Methods

The relevant domestic and abroad literature on the clinical application of MSAPF was extensively consulted, and the research progress were summarized and analyzed in aspect of its definition, anatomical characteristics, clinical application, surgical resection and improvement, and advantages and disadvantages of flaps, etc.

Results

MSAPF has the advantages of relatively constant anatomical position, thin flap texture, long vascular pedicle, large vessel diameter, no sacrifice of main blood vessels, concealed donor site, no hair, and fewer complications; it can carry nerves, tendons, and muscles to construct chimeric flaps to repair three-dimensional wounds; and can also repair wounds with high aesthetic and functional requirements such as hand, foot and ankle, head and neck, etc.

Conclusion

The MSAPF is a versatile, various forms, functional diversification, and three-dimensional flap donor site with various application forms and ideal repair effectiveness.

Evaluation of Primary and Secondary Free Flap Desyndactylization Techniques in Hand and Digit Reconstruction: A Systematic Review

Objective Injuries of the hand often require free flap reconstruction. To minimize flap loss, evidence exists to surgically syndactylize digits when repairing multiple injuries, with delayed flap division, or desyndactylization. However, evidence suggests that division of the flap at the time of inset can be accomplished with minimal negative effect. The purpose of this study was to evaluate outcomes, following hand reconstruction with free flaps utilizing either acute or staged desyndactylization techniques.

Methods A systematic review utilizing the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was performed. Articles that described the use of a free flap for surgically syndactylized digits or multilobed flaps for coverage of multiple digits were included.

Results One hundred sixty-one articles were reviewed with 34 fulfilling inclusion criteria. One hundred seventeen patients underwent 145 free flap reconstructions. Traumatic avulsions (49%) were the most common injuries, followed by burns (11%). Twenty-one (62%) papers described surgical syndactylization of digits, which were later desyndactylized and five (15%) papers included reconstruction of more than one digit with multilobed free flaps. Eight papers (24%) described both techniques. Overall, 100% of included flaps survived. Total complication rate was 6%, with six complications (67%) occurring in flaps with primary syndactylization.

Conclusion Hand defects often require free flaps for reconstruction. Although free flaps for the reconstruction of digital defects is technically demanding, they result in better outcomes. With available evidence indicating complications rates less than those of staged desyndactylization, multidigit reconstruction with multilobed free flaps may be a more desirable technique.

Extended Use of Chimeric Medial Sural Artery Perforator Flap for 3-Dimensional Defect Reconstruction

BACKGROUND

The medial sural artery perforator (MSAP) flap has become increasingly popular because it is thin and pliable for small to moderate defect soft tissue reconstruction. Furthermore, chimeric MSAP flap, which includes a skin paddle and a separated piece of medial gastrocnemius muscle, allowed more freedom for flap insetting, especially in 3-dimensional defect reconstruction. Here we describe our experience regarding this clinical application.

PATIENTS AND METHODS

From 2007 to 2016, 14 male patients (average age, 46.9 ± 14.4 years) who received either a free or pedicled chimeric MSAP flap were included. Of these 14 patients, 7 received this flap for reconstruction in the head and neck, 2 in the upper extremities, and 5 in the lower extremities. Demographic data were collected and analyzed, and a literature review was performed.

RESULTS

Ten patients received free chimeric MSAP flap, and 4 received the pedicled type. Thirteen of the 14 flaps (92.6%) survived, and 1 failed 2 days later owing to venous insufficiency. Venous congestion-related partial loss occurred in another case.

CONCLUSIONS

The chimeric MSAP flap is a good alternative for deep space obliteration or reconstruction of adjacent but separate defects in both free and pedicled flap design. Donor site morbidity is limited. However, the perforator needs to be mobilized carefully to prevent postoperative venous compromise.

Anatomical study and clinical application of medial sural artery perforator flap for oral cavity reconstruction

The present study aims to provide anatomical evidence for clinical application of the medial sural artery perforator (MSAP) flap. The current study investigated the vascular anatomy of the flap, evaluated the postoperative appearance and function of the donor and recipient sites, and investigate the clinical value in reconstruction of oral cavity. Six lower limbs of Chinese adult cadavers were microsurgically dissected. The locations and courses of the medial sural artery perforators were identified and recorded, which provided an anatomical basis for clinical application. Then, 16 clinical cases employing this flap were evaluated, ranging from 3×4cm to 6×8cm, and were employed for defects in the oral cavity region. Sixteen clinical cases with intraoral soft tissue defects, which included four clinical cases with inner cheek defects, were successfully followed up for 10-47 months (24 months on average). The donor site function, contour of recipient site and oral function recovery were evaluated as acceptable or better in cases with intraoral soft tissue defect, which were further verifying the value of clinical application of MSAP in repairing oral cavity defects. Moreover, two typical clinical cases were described in detail. To conclude, the MSAP flap is a favorable choice for small- to medium-size defects based on minor donor site morbidity, satisfactory oral function recovery, perforator stability and adaptation of the pedicle for anastomosis in the oral cavity region.

The free medial sural artery perforator flap: Versatile option for soft tissue reconstruction in small-to-moderate size defects of the foot and ankle

BACKGROUND

The medial sural artery perforator (MSAP) flap shows advantages for reconstruction in the foot and ankle, where bulk is a liability. We evaluated the versatility of this flap and provide further evidence on its use for covering small-to-moderate size defects by comparing the outcome depending on the region of reconstruction.

METHODS

Twenty-two patients with variable defects of 4 × 4 to 18 × 7 cm underwent MSAP flap reconstruction. Final outcomes of all patients were evaluated 12-months postoperatively using the AOFAS ankle-hindfoot, midfoot and hallux scale for clinical-functional evaluation, and the SF-36 health survey for quality-of-life measurement. The scores were compared in three groups according to the anatomic region of MSAP flap reconstruction.

RESULTS

The flap size ranged between 6 × 4 and 21 × 9 cm. One venous congestion was salvaged by venous thrombectomy and reanastomosis, and one marginal flap necrosis healed by secondary intention. All flaps survived, and all patients returned to ambulation. Patients with reconstruction of the ankle-hindfoot or hallux showed significantly lower AOFAS ankle-hindfoot (P = 0.021) or hallux scores (P = 0.034), whereas reconstruction of the midfoot led to equal AOFAS midfoot scores (P = 0.265) as compared with patients without reconstruction in the respective region. Comparison of SF-36 physical (P = 0.936) and mental (P = 0.855) scores of all three regions remained insignificant.

CONCLUSION

The MSAP flap provides thin soft tissue coverage, enabling good functional recovery after defect reconstruction all around the foot and ankle, with evident advantages in the midfoot. However, the functional outcomes after reconstruction of the ankle-hindfoot or hallux region depend on the preexistent functional impairment.