A Comparative Clinical Study of Flap Thickness: Medial Sural Artery Perforator Flap Versus Anterolateral Thigh Flap

Characterization of the MSAP Flap in Head and Neck Surgical Oncology: A 3D Cadaveric Study

OBJECTIVES

The medial sural artery (MSA) perforator flap is a versatile free flap. However, the cutaneous perforators are not well characterized. The objectives of this pilot anatomical study were to: (1) visualize in three-dimensions, as in-situ, the origin, course, and distribution of the cutaneous perforators, (2) characterize the number and frequency of the perforators, and (3) quantify mean pedicle length.

METHODS

Thirteen cadaveric specimens were dissected, digitized, and modeled in 3D. Three-dimensional models and dissection photographs were used to determine the origin, course, number, distribution, and pedicle length of MSA perforators.

RESULTS

The most common pattern consisted of three perforators (39% of specimens). The maximum number of perforators identified was four (23%). The majority of specimens (92%) had a cutaneous perforator originating from the lateral branch of the MSA and coursed most frequently in the second (43%) and third (37%) quartiles of the length of the tibia. Mean pedicle length was 19.1 ± 6.9 cm. Perforators originating from the medial branch of the MSA were significantly (p < 0.05) shorter than those from the lateral branch and were found to course only in the first quartile.

CONCLUSION

The 3D models constructed in this study provide a comprehensive overview of the location and course of the perforators, enabling measurement of parameters in 3D-space. Anatomical characterization of the MSA perforator flap using 3D analysis can assist reconstructive surgeons in understanding the relevant anatomy and optimizing the surgical technique for flap harvest.

LEVEL OF EVIDENCE

N/A Laryngoscope, 2024.

Comparison of The Thickness of Free Anterolateral Thigh Flap in Different Fascial Planes: Clinical Results of Subfascial and Superficial Fat Flap

Background  The anterolateral thigh (ALT) flap is a preferred option in the reconstruction of a wide variety of defects, enabling multiple tissue components and thicknesses. Methods  This study was conducted to investigate the correlation of the thickness of the traditional subfascial ALT flap and superficial fat flap with age, gender, and body mass index (BMI). A total of 42 patients (28 males and 14 females) were included in the study. Results  Mean age was 50.2 (range, 16-75) years and mean BMI was 24.68 ± 4.02 (range, 16.5-34.7) kg/m 2 . The subfascial flap thickness was significantly thinner in male patients (16.07 ± 2.77 mm) than in female patients (24.07 ± 3.93 mm; p  < 0.05), whereas no significant difference was found between male (4.28 ± 1.15 mm) and female patients (4.85 ± 1.09 mm) regarding superficial fat flap thickness ( p  = 0.13). The thickness of both flaps had a positive correlation with BMI, and the strongest correlation was found for subfascial ALT thickness in female patients ( r  = 0.81). Age had no effect on both flap thickness measurements. The anterior thigh is thicker in women than in men, although it varies according to BMI. This shows that flap elevation is important in the superthin plane, especially if a thin flap is desired in female patients in defect reconstruction with the ALT flap. Thus, a single-stage reconstruction is achieved without the need for a defatting procedure after subfascial dissection or a second defatting procedure 3 to 6 months later. Conclusion  The appropriate ALT flap plane should be selected considering the gender and BMI of the patient.

A 10-year experience in microsurgical reconstruction of the nose with a lower extremity flap

BACKGROUND

Traditionally, radial forearm free flaps are utilized for nasal lining reconstruction when local flaps cannot provide adequate coverage. However, according to our clinical observation, the skin of the forearm flap is relatively thin and prone to collapse. We present a series of nasal reconstructions using free flaps harvested from the lower extremities to determine if the thick flap could provide more support and decrease the tendency of airway collapse.

METHODS

From March 2011 to July 2021, we identified 15 patients who underwent total or subtotal nasal reconstruction with free flap from the lower extremities (10 anterolateral thigh flap, 4 medial sural artery perforator flap, and 1 profunda artery perforator flap). We included 15 patients who underwent free forearm flap reconstruction as controls. The Nasal Obstruction Symptoms Evaluation (NOSE) score was utilized to subjectively evaluate the degree of nasal obstruction symptoms.

RESULTS

The lower extremity group had a lower NOSE score than the forearm group (25.4 vs. 40). It took more time (6.5 vs. 4.2 months) and more surgeries (4.6 vs. 2.6) from the first free flap reconstruction till forehead flap reconstruction in the lower extremity group than in the forearm group, although the total number of surgeries was comparable between the 2 groups (7.2 vs. 8.1).

CONCLUSIONS

Utilizing free flaps from the lower extremities in total or subtotal reconstruction of the nasal lining may decrease the tendency of flap collapse and alleviate airway obstruction symptoms and may also allow reconstruction of surrounding defects simultaneously compared with using forearm flaps.

Ultrathin Anterolateral Thigh Free Flap: An Adipocutaneous Flap with the Most Superficial Elevation Plane

BACKGROUND

Although many efforts have been made to create thinner anterolateral thigh (ALT) flaps, their thickness varies among patients, and the flap may be still too thick to match shallow defects. The authors successfully harvested an ALT flap through the most superficial elevation plane, the superficial fat layer, which was useful to match the shallow defects.

METHODS

All patients who underwent ALT free flap reconstruction for upper and lower distal extremity defects were divided retrospectively into groups by ALT flap elevation plane: thin, above the deep fascia; superthin, at the superficial fascia; and ultrathin, through the superficial fat. Preoperative computed tomographic angiography and duplex ultrasonography planning were used for all patients. Anatomical characteristics of donor subcutaneous tissue and surgical details, including flap thickness, flap size, and incidence of flap necrosis were compared among the groups and between sexes.

RESULTS

The average deep and superficial fascial depths were 16.7 and 10.8 mm, 12.5 and 8.2 mm, and 9.1 and 5.6 mm ( P < 0.05), and the average flap thickness was 5.8 mm, 7.9 mm, and 7.8 mm ( P = 0.29) in the ultrathin, superthin, and thin ALT groups, respectively. No significant intergroup differences existed in flap size or complications. The deep and superficial fascia were located significantly deeper in female patients (9.4 and 6.0 mm in male patients and 14.9 and 9.6 mm in female patients, respectively).

CONCLUSIONS

With precise preoperative planning, the most superficially elevated, ultrathin ALT flap can achieve optimal reconstructions of thin body areas. Female patients with thicker thighs and patients with a high body mass index would benefit from this flap.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

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.

Reconstruction of Upper and Lower Limb Defects with Medial Sural Artery Perforator Flaps: Is Aesthetics Worth the Effort? A Retrospective Analysis

Background  One of the most essential goals in managing complex limb defects is obtaining adequate soft tissue coverage with excellent functional and aesthetic outcomes. Free perforator skin flaps represent an optimal option for such defects. Therefore, our intention was to reconstruct these kinds of defects with thin fasciocutaneous flaps without the need for debulking. Herein, we define the legitimate use of the medial sural artery perforator (MSAP) flaps for small-moderate size defect coverage of the hand and foot. Patients and Methods  Seven patients received MSAP flaps for reconstruction of different hand and foot defects, of which the majority were males (4/7). Age, sex, flap size, location, number of perforators, recipient vessel, type of anastomosis, technique of donor site closure, and postoperative morbidity were recorded. Patients' age ranged from 48 to 84 years. Results  Single-stage debridement followed by reconstruction was performed. Flap sizes ranged from 6 to 18 cm in length and 4 to 10 cm in width. The pedicles of 6 flaps were anastomosed to the tibial artery system (three posterior tibial artery, three dorsalis pedis artery) and one to the ulnar artery. Conclusion  MSAP flap can be a versatile option for single-stage reconstruction of small-moderate size defects of the extremities, where thin, soft tissue envelope is required. This flap has lower donor site morbidity, more tedious elevation process, and has a good reconstructive and aesthetic result without the need for debulking in the future.

The profunda artery perforator flap for head and neck reconstruction

INTRODUCTION

The profunda artery perforator (PAP) fasciocutaneous flap is underutilized in head and neck reconstruction, with advantages including ease of harvest and minimal donor site morbidity.

METHODS

Cadaveric dissection of cutaneous perforators to origin at profunda femoris system to characterize vascular anatomy.

RESULTS

22 PAP flaps were studied. Each contained 1-6 cutaneous perforators originating from the profunda system, designated into A, B, or C vascular pedicle systems. Muscular perforators did not consistently extend to skin in systems A and C, but all dissections demonstrated myocutaneous perforator in system B. Average distance from groin crease to cutaneous perforators of A, B, and C respectively was 8 cm (range 3-15 cm), 11.4 cm (range 5-17 cm), and 17.5 cm (range 12.5-22 cm). Average pedicle length was 11.07 cm (range 7-16 cm), 11.78 cm (range 9-16 cm), and 11.23 cm (range 9-15 cm). Average vena comitans diameter at origin was 3.14 mm (range 1.27-4.46 mm). Average arterial diameter at origin was 2.07 mm (range 1.27-3.82 mm). Range of maximal primary closure was 6-11 cm.

CONCLUSION

PAP free flap demonstrates reliable vascular anatomy in cadavers, with adequate pedicle length and vessel diameter. All specimens contained adequate myocutaneous perforator to support free tissue transfer.

Cross-legged modification for medial sural artery perforator flap harvest

When thin and pliable free tissue is needed, the medial sural artery perforator (MSAP) flap provides an excellent option with minimal donor site morbidity. However, among its pitfalls include difficult patient positioning and surgeon ergonomics throughout the harvest. We describe a novel positioning technique that may significantly improve surgeon ergonomics and ease of MSAP flap harvest. A cross-legged modification may eliminate many of the issues associated with the classic frog-leg position. While the patient is cross-legged, the surgeon is afforded a normal field of view that is closer to their body, while simultaneously providing support to the lateral side of the gastrocnemius muscle. This pictorial essay describes this positioning technique and subsequent harvest. By incorporating a more ergonomic cross-legged position during flap elevation, many of thedrawbacks of the MSAP flap could be eliminated.

[Reconstruction of posttraumatic soft tissue defects of the ankle using free fascial flaps from the anterolateral thigh]

BACKGROUND

Free fascial flaps from the anterolateral thigh (ALT) were used to reconstruct soft tissue defects after trauma to the ankle. This modification was compared to the conventional fasciocutaneous method.

MATERIAL AND METHODS

The defect size, the thickness of the subcutaneous fat layer on the thigh and the extent of the soft tissue covering the ankle were determined retrospectively. The evaluations were compared between fascial (Fo) and fasciocutaneous flaps (Fc). The foot and ankle outcome score (FAOS) was used. Esthetic outcome surveys were carried out.

RESULTS

A total of 18 isolated fractures of the ankle were evaluated. In 94% of the cases a closed soft tissue damage predominated. After fracture fixation using a plate, soft tissue defects with a mean area of 40.4 ± 13.1 cm2 (28-76 cm2) developed. The thickness of the soft tissue covering over the affected malleoli increased significantly in both groups as a result of the flap surgery (4.5 ± 0.7 vs. 21.1 ± 6.4 mm, p < 0.05). A significant difference was found when comparing the body mass index (BMI) between the groups (Fc 26.3 ± 3.4 kg/m2 vs. Fo 30.1 ± 4.2 kg/m2, p < 0.05). For both groups there was a positive correlation (r = 0.843) between the BMI and the thickness of the epifascial fat layer of the thigh. The FOAS survey revealed 75.9 ± 28.9 and 47.9 ± 32.4 points, respectively, for "function in daily life" and "foot and ankle-related quality of life". The esthetic reconstruction result was rated as "acceptable" by 55% and as "good" by 45%.

DISCUSSION

The modified method of a free fascial flap from the ALT can be useful in situations where a bulky flap makes it difficult to fit it into the defect.

Does leg dominance influence anterolateral thigh flap perforators?

INTRODUCTION

Thorough knowledge of perforator anatomy can facilitate anterolateral thigh (ALT) free flap harvest. The selection of the right or left thigh as donor area may be supported by preoperative perforator imaging and practical considerations. The study aims to determine if the leg dominance should be taken into account, when choosing the donor thigh for ALT free flap harvest, as muscle mass and perfusion might influence perforator quantity.

METHODS

ALT perforators were localized by color-coded duplex sonography and dynamic infrared thermography on both thighs within a defined 250 × 80 mm area in 24 subjects. Perforator number and thickness of subcutaneous tissue and muscle layer were compared in dominant and nondominant legs.

RESULTS

We found no statistically significant difference comparing sonographically identified ALT perforator numbers and hot spot numbers in dominant and nondominant legs. Yet, we found high interindividual differences. The comparison of subcutaneous tissue and muscle thickness yielded no significant difference.

CONCLUSIONS

Our study yielded no evidence for preference of the dominant or nondominant leg in ALT free flap harvesting. As we found high interindividual differences in perforator number, we suggest to rely on preoperative perforator imaging when choosing the ALT free flap donor thigh.

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.

Clinical study on orthopaedic treatment of chronic osteomyelitis with soft tissue defect in adults

To investigate the clinical application value of different flap transfer and repair techniques in adult patients with chronic osteomyelitis of limbs complicated with soft tissue defects. According to the characteristics and defects of 21 cases, different plastic surgery was applied, including debridement, negative pressure device, and tissue flap to cover wound. Among 21 cases of chronic osteomyelitis complicated with local soft tissue defect, 15 patients were repaired with sural neurotrophic musculocutaneous flap transfer, 2 patients were repaired with medial plantar skin flap transfer, 2 patients were repaired with ilioinguinal skin flap transfer, 1 patient was repaired with z‐forming wound, and 1 patient was repaired with soleus muscle flap combined with full‐thickness skin graft. All the 21 patients underwent bone cement implantation after dead bone osteotomy. Among them, 19 patients underwent bone cement replacement with 3D prosthesis within 6 months to 1 year after surgery, and 2 patients carried bone cement for a long time. Early intervention, thorough debridement, removal of necrotic or infection, and then selecting the appropriate wound skin flap coverage are important means of guarantee slow osteomyelitis wound healing and for providing a possible way to permanent prosthesis implantation subsequently.

Free ALT Perforator Flap in Nonobese Patients: The Recontouring of Soft Tissue Defects Around Foot

BACKGROUND

The anterolateral thigh (ALT) perforator flap is well-described and versatile option for reconstruction of soft tissue defects around foot and ankle. This retrospective review was performed for reconstruction of soft tissue defects around foot with ALT perforator flaps in patients with normal and overweight body mass index (BMI).

METHODS

Between January 2016 and November 2020, ALT flaps were used in 30 patients for foot defects.

RESULTS

Etiologic factors were trauma (18 patients), diabetic foot ulcer (6 patients), tumor (3 patients), infection (2 patients) and burn contracture (1 patient). Mean body mass index (BMI) value was 24.9 ± 4.1 (17-30). Mean flap dimension was 145 ± 86 (40-420) cm². Recipient vessels were anterior tibial artery in 17 patients (56%), posterior tibial artery in 12 patients (40%), reversed flow dorsalis pedis artery in 1 patient (3.3%). In 24 patients (80%), 2 vein anastomoses were done. Debulking were applied in two patients (6.6%). Donor area was grafted in four patients (13.3%). Mean flap score was 1.25 ± 0.5. Mean flap thickness was 10 ± 2 (7-14) mm. Visual Analogue Scale (VAS) score was 7.75 ± 1.04 (6-10). The patients were followed up for a mean of 14 ± 11 (1-30) months.

CONCLUSION

We think that ALT flap is still reliable and precious option because it provides ideal soft tissue reconstruction by means of recontouring of foot in nonobese patients.

Influence of BMI, Age, and Gender on the Thickness of Most Common Thinned Flaps

Background:

Since the description of superficial fascia flap harvesting, a new window of opportunity has been open in obese patients, where a higher subcutaneous thickness of tissue is present. To our knowledge, the impact of body mass index on superficial fascial flaps has not been reported.

Methods:

We recruited 122 patients from April 2019 to January 2020. From these patients, the 3 most common thinned flaps were selected: the superficial circumflex iliac perforator flap; the anterolateral thigh flap at the perforator A, B, and C; and the thoracodorsal flap. Two vertical measures were registered: the distance from the skin to the superficial fascia, and from this point to the deep fascia.

Results:

The average flap measurement presented here was within the range, as previous clinical studies. The superficial fatty layer thickness in the superficial circumflex iliac perforator and anterolateral thigh flap was somewhat similar in thickness between overweight and obese patients, showing a minimal increase with higher body mass index. The anterolateral thigh flap was found thicker among women, and no statistical difference was shown between age groups in any of the flaps.

Conclusions:

A better understanding of the fat layers’ thickness will result in better planning, minimizing secondary debulking procedures, decreasing operative time, and reducing general complications among obese patients. Thus, a better understanding of flap structure and physiology in obese patients will lower complications and give more predictable results.

The medial sural artery perforator (MSAP) flap: A versatile flap for lower extremity reconstruction

BACKGROUND

The medial sural artery perforator (MSAP) flap provides a thin, pliable and durable soft tissue reconstruction with adequate pedicle length and low donor morbidity. It is an ideal choice for small-to-moderate defects of the lower extremity, although it does have limitations. We report our experience of the flap in a three-pronged anatomical, clinical and patient reported outcome-based study.

METHODS

Cadaveric fresh frozen lower limbs (n = 10) were used for anatomical dissections to assess pertinent and clinically relevant findings. Data relating to MSAP flaps was collected from a prospectively maintained database over a 2-year period. Both clinical data and modified Enneking scores were analysed.

RESULTS

Anatomical study: A mean of 2.1 ± 0.99 perforators arose from the medial sural artery, located 11.9 cm ± 2.07 along the line between the popliteal fossa and medial malleolus. The largest perforator was located 13.58 cm ± 2.01 from the popliteal artery. The distance from the dominant perforator to the first branching point within the gastrocnemius was 7.39 ± 1.50 (range 5-9.2 cm). The short saphenous vein was located on average 3.08 cm ± 0.77 from the dominant perforator. Clinical study: Twenty free and nine pedicled MSAPs were included (n = 29). Open lower limb fractures (n = 18, 62%) and infection (n = 10, 35%) were the most common aetiologies. Defects sites included: foot-and-ankle (n = 12, 55%), knee (n = 9, 31%) and anterior leg (n = 4, 14%). Four patients (14%) required SSG to for donor site coverage. Venous congestion was responsible for partial flap necrosis in 6.9%(n = 2) of patients. All wounds were healed at discharge. At 14 months, the mean Enneking score was 72.5%. All patients were ambulant, 96% returned to work and 87% were using pre-operative footwear.

CONCLUSIONS

The MSAP provides robust foot-and-ankle reconstruction, whilst permitting glide when over the knee. Patient satisfaction and functional outcomes are excellent with careful patient selection. Care should be taken to avoid compression or kinking of the large, thin walled veins as the most commonly observed complication was venous congestion. We advocate MSAP as a first choice flap for small-to-moderate foot, ankle or knee defects.