A Head-to-Head Comparison of the Medial Sural Artery Perforator versus Radial Forearm Flap for Tongue Reconstruction

Medial sural artery perforator flap in head & neck reconstruction

PURPOSE OF REVIEW

This review focuses on the recent advancements in the application of the medial sural artery perforator (MSAP) flap for head and neck reconstruction. It highlights key anatomical findings, surgical techniques, comparative outcomes, and future perspectives from the last 1-3 years of research.

RECENT FINDINGS

The MSAP flap has emerged as a reliable option for head and neck reconstruction due to its thin, pliable nature and minimal donor-site morbidity. Recent anatomical studies have refined understanding of its vascular consistency, with perforators located 8-12 cm distal to the popliteal crease and pedicle lengths averaging 10.1 cm. Functional outcomes demonstrate superiority over bulkier alternatives such as the anterolateral thigh flap, particularly in intraoral reconstructions, while donor-site morbidity remains significantly lower than that of the radial forearm free flap.

SUMMARY

The MSAP flap provides an optimal balance of form and function for complex head and neck reconstructions. Its consistent anatomy and favorable postoperative outcomes underscore its growing role in modern reconstructive surgery. Further multicenter trials are essential to establish standardized protocols and enhance outcomes.

An Overview Algorithm for Perforator Free Flap Coverage of all Zones of the Mangled Upper Extremity

A truly mangled upper extremity will undoubtedly need composite tissue rearrangement to ensure adequate wound healing; but often also the replacement of missing parts, always with the goal of maximizing functional rehabilitation. Whatever the approach, restoration of the cutaneous envelope surrounding the underlying repaired musculoskeletal system will be mandatory. Vascularized tissues as flaps frequently will be essential to accomplish this goal; however, intrinsic local donor sites not only may not be available due to the injury itself or if chosen would contribute to further injury. Instead, microvascular tissue transfers will play an important role. In this regard, the perforator free flap today has gained prominence as "like can replace like," sensibility is restored, secondary procedures are more simply approached, and donor site morbidity is reduced since no muscle needs to be sacrificed, maximizing function preservation. However, perforator flap donor sites are highly variable, providing another attribute that, on selection, may best meet the requirements for the involved zone of the upper extremity.

Medial sural artery perforator free flap versus radial forearm free flap in oral cavity reconstruction and donor site morbidity

OBJECTIVE

Radial Forearm Free flap (RFFF) is widely used in head and neck reconstruction, yet its donor site defect remains a significant drawback. The Medial Sural Artery Perforator Free Flap (MSAPFF) is considered an alternative flap to RFFF. This study aims to comprehensively analyze their characteristics, outcomes, and their impact on patient quality of life.

METHODS

All patients who underwent oral cavity reconstruction using RFFF and MSAPFF between February 2017 and April 2023 were included in this study. Flap characteristics, outcomes and post-operative complications were recorded and compared. Subjective donor site morbidity, aesthetic and functional results, and quality of life were also analyzed.

RESULTS

The study included 76 patients: 37 underwent reconstruction with RFFF, and 39 with MSAPFF. There was no significance difference between the RFFF and MSAPFF regarding the success rate (97.2% vs 97.4%), flap size (4.8 × 8.8 cm2 vs 5 × 9.8 cm2), hospital of stay (15.5 days vs 13.5 days) and recipient site complications (P > 0.05). However, MSAPFF showed larger flap thickness (P = 0.001), smaller arterial caliber (P = 0.008), shorter pedicle length (P = 0.001), and longer harvesting time (P < 0.001). No significant difference was observed between the pre-and postoperative ranges of wrist and ankle movements or in recipient site complications. MSAPFF showed a significant difference in donor site morbidity (P < 0.05).

CONCLUSION

The MSAPFF is an excellent alternative to the RFFF for repairing oral cavity defects, with additional advantage of a well-hidden scar on the posterior calf, a larger flap thickness, accepted pedicle length and arterial caliber. However, one should consider the harvesting time and surgical skills required in comparison to the RFFF.

CLINICAL RELEVANCE

The study highlights the importance of the MSAPFF as an alternative option for RFFF with less donor site morbidity and high success rate in oral cavity reconstruction and improved patient Quality of life after ablative surgery.

Expanding the Armamentarium of Donor Sites in Microvascular Head and Neck Reconstruction

The field of microsurgical head and neck reconstruction has witnessed tremendous advancements in recent years. While the historic goals of reconstruction were simply to maximize flap survival, optimizing both aesthetic and functional outcomes has now become the priority. With an increased understanding of perforator anatomy, improved technology in instruments and microscopes, and high flap success rates, the reconstructive microsurgeon can push the envelope in harvesting and designing the ideal flap to aid patients following tumor extirpation. Furthermore, with improvements in cancer treatment leading to improved patient survival and prognosis, it becomes increasingly important to have a broader repertoire of donor sites. The present review aims to provide a review of newly emerging soft tissue flap options in head and neck reconstruction. While certainly a number of bony flap options also exist, the present review will focus on soft tissue flaps that can be harvested reliably from a variety of alternate donor sites. From the upper extremity, the ulnar forearm as well as the lateral arm, and from the lower extremity, the profunda artery perforator, medial sural artery perforator, and superficial circumflex iliac perforator flaps will be discussed, and we will provide details to aid reconstructive microsurgeons in incorporating these alternative flaps into their armamentarium.

Medial Sural Artery Perforator Flap: A Middle Ground Between Anterolateral Thigh and Radial Forearm Flaps

OBJECTIVE

The medial sural artery perforator (MSAP) flap has gained popularity in head and neck reconstruction primarily as a less morbid alternative to the radial forearm free flap (RFFF). However, no direct comparison of thickness exists among the MSAP, RFFF, and anterolateral thigh (ALT) flaps, which together represent the commonly utilized nonosseus-free flaps in head and neck reconstruction. Thus, this study aimed to compare these flap sites and identify predictors of thickness that will aid in reconstructive surgical planning.

STUDY DESIGN

Cross-sectional study.

SETTING

Tertiary referral hospital.

METHODS

The thickness of skin and subcutaneous tissue at the RFFF, MSAP, and ALT donor sites were measured in 54 adult patients using Doppler ultrasound. General linear models were generated to identify predictors of flap thickness.

RESULTS

The mean thickness of the RFFF, MSAP, and ALT flaps was 3.8 ± 2.2 mm, 7.4 ± 3.8 mm, and 9.6 ± 4.7 mm. Body mass index (BMI) was the only statistically significant contributing factor (p < .0001, coefficient: 0.15) for the RFFF. MSAP was affected by age (p = .006, coefficient = 0.06), female gender (p < .0001, coefficient = 3.2), and BMI (p < .001, coefficient = 0.25), while the ALT was affected by female gender (p = .0005, coefficient = 3.3) and BMI (p < .0001, coefficient = 0.35). Thus, the ratio of increase for flap thickness with respect to BMI is 3:5:7 for the RFFF, MSAP, and ALT flaps, respectively.

CONCLUSION

The MSAP is about twice the thickness of the RFFF and 2 mm thinner than the ALT; however, 22% of patients had thicker MSAP than ALT flaps. As the strongest predictors of flap thickness, female gender, and BMI may be taken into consideration during surgical planning for reconstruction.

The Medial Sural Artery Perforator Flap versus Other Free Flaps in Head and Neck Reconstruction: A Systematic Review

The medial sural artery perforator (MSAP) flap is a versatile fasciocutaneous flap, and yet is less commonly utilized than other free flaps in microvascular reconstructions of the head and neck. The aim is to conduct a high-quality Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA)- and Assessment of Multiple Systematic Reviews 2 (AMSTAR 2)-compliant systematic review comparing the use of the MSAP flap to other microvascular free flaps in the head and neck. Medline, Embase, and Web of Science databases were searched to identify all original comparative studies comparing patients undergoing head and neck reconstruction with an MSAP flap to the radial forearm free flap (RFFF) or anterolateral thigh (ALT) flap from inception to February 2021. Outcome studied were the recipient-site and donor-site morbidities as well as speech and swallow function. A total of 473 articles were identified from title and abstract review. Four studies met the inclusion criteria. Compared with the RFFF and the ALT flaps, the MSAP flap had more recipient-site complications (6.0 vs 10.4%) but less donor-site complications (20.2 vs 7.8%). The MSAP flap demonstrated better overall donor-site appearance and function than the RFFF and ALT flaps ( p  = 0.0006) but no statistical difference in speech and swallowing function following reconstruction ( p  = 0.28). Although higher quality studies reviewing the use of the MSAP flap to other free flaps are needed, the MSAP flap provides a viable and effective reconstructive option and should be strongly considered for reconstruction of head and neck defects.

Comparison of Current Free Flap Options for Intraoral Lining and Tongue Reconstruction

Free flaps have become the main alternative for intraoral reconstruction in current practice. However, controversy exists on pros and cons of different free flap options for this challenging area. Although there are various studies focusing on different free flap options, comparative studies are very few and there is not a single study comparing all 4 thin free flap options for intraoral reconstruction. Between 2018 and 2021, 30 patients underwent intraoral reconstruction. Four pliable and thin flaps, medial sural artery perforator flap, superficial circumflex iliac artery perforator flap, radial forearm free flap, and superthin anterolateral thigh flap were used for reconstructions and compared per functionality and patients' quality of life. One medial sural artery perforator flap and 1 superficial circumflex iliac artery perforator flap failed because of perfusion problems, and the remaining flaps survived. Harvest time and donor site closure were with significant difference ( P <0.05) between groups. Quality of life results were similar except one of the disease-specific questions. In authors' opinion, anterolateral thigh flap is the best option in normal-weight individuals because of its reliability, pliability, and constant reliable vascular structure. Although other options may be considered in overweighted patients, thinly elevated anterolateral thigh flap still seems to be the most reliable option.

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.