The Medial Sural Artery Perforator Flap: The First Choice for Soft-Tissue Reconstruction About the Knee

The myocutaneous gastrocnemius flap for periprosthetic joint infection of the knee

Purpose

Periprosthetic joint infection (PJI) following total knee arthroplasty (TKA) presents significant challenges, especially in elderly and comorbid patients, often necessitating revision surgeries. We report on a series of patients with confirmed PJI of the knee and concomitant soft-tissue/extensor apparatus defects, treated by using pedicled myocutaneous medial or lateral sural artery perforator (MSAP/LSAP) gastrocnemius flaps.

Methods

Our retrospective study at the Center for Musculoskeletal Infections, included patients with knee PJI undergoing pedicled myocutaneous MSAP/LSAP gastrocnemius flap reconstruction for combined soft tissue and extensor apparatus defects. The tendinous back of the gastrocnemius muscle was used and, if required, the Achilles tendon for extensor apparatus reconstruction, with the skin island addressing the cutaneous defect. Perioperative complications and postoperative outcomes after 1 year were evaluated, including functional and clinical assessments with the American Knee Society Score (AKSS).

Results

Eight patients (mean age 73 years; five female) were included, predominantly with Staphylococcus aureus infections. Six patients involved isolated MSAP flaps, two were extended with the Achilles tendon. The median time for wound healing was 9 days. Short-term follow-up showed successful reconstruction in seven patients, with minor wound dehiscence in one patient. One patient required flap revision for a perigenicular haemato-seroma and two patients were diagnosed with new haematogenous PJI infection. Significant improvement in AKSS scores after surgery was observed (functional AKSS: median 33-85; clinical AKSS: median 64-91, p = 0.001).

Conclusion

Pedicled myocutaneous MSAP/LSAP gastrocnemius flaps offer a safe, reliable and versatile option for reconstructing combined soft tissue and extensor apparatus defects in PJI after TKA. This approach yields excellent functional outcomes with minimal peri- and postoperative complications, which is particularly beneficial in elderly and comorbid patients and feasible in settings without microsurgical availability.

Level of evidence

Level IV.

Application of Staged Negative Pressure Wound Therapy and Flap Surgery for Infection Control After Patellar Internal Fixation Surgery

The anatomic position of the patella is superficial, making it vulnerable to injuries. Treatment of patella infection after internal fixation surgery remains a big challenge due to minimal soft tissue coverage and vital tissue exposure. Forty-two patients aged 10 to 59 years were admitted to the institution's burn unit between January 2010 and December 2019. Each presented with infection after patellar fracture surgery. Twenty-seven infections were superficial, whereas 15 were deep with pyogenous arthritis of the knee. Negative pressure wound therapy (NPWT) was applied after radical debridement to remove necrotic subcutaneous tissues and internal fixation devices. In addition, cases with septic arthritis were irrigated continuously with normal saline. After 5 to 10 days of NPWT treatment and irrigation, wound infection was well controlled. Afterward, 42 wounds were resurfaced with pedicled flaps, the 42 patients received 17 reverse-flow anterolateral thigh (ALT) perforator flap, 12 medial sural artery perforator flaps, 7 gastrocnemius musculocutaneous flaps, as well as 6 saphenous artery flaps. Thirty-seven flaps survived uneventfully. However, 3 flaps developed venous congestion in the distal end. Two flaps developed tip necrosis. All patients were followed up between 3 and 48 months. Infection beneath the flap occurred in 3 patients and healed after an additional debridement surgery. The staged NPWT and flap surgery strategy focus on thorough debridement and immediate internal fixation devices removal, effective fracture fixation, efficient NPWT application, targeted administration of antibiotics, and adequate soft tissue coverage. This study established that the procedure was effective in infection control after patellar internal fixation surgery.

Pedicled double-paddle conjoined medial sural artery perforator flap for popliteal defect coverage after skin tumor excision: A case report

Defect coverage in the popliteal region represents a challenging task because of its peculiar features. The tissue here has to be thin and pliable, to enable proper function, but also resistant to the high stress forces typical of this region. In addition, the adjacent skin is limited in availability and mobility. Therefore, complex reconstruction procedures are usually required to cover defects in the popliteal region. The medial sural artery perforator (MSAP) flap is a thin and pliable flap, with a long arc of rotation provided by its pedicle length, which makes it a suitable procedure for local and regional defects reconstruction. In the present work, we report the use of a pedicled double-paddle conjoined MSAP flap to reconstruct a 7 cm × 7 cm soft tissue defect after resection of a basal cell carcinoma in the popliteal fossa. The MSAP flap was based on two perforators of the medial sural artery. Therefore, the cutaneous island could be split into two islands, which were rearranged to cover the defect side by side in a so-called "kissing flap" technique. The further postoperative course was uneventful. Despite the complex perforator dissection, which can be challenging because of its intramuscular dissection, we believe that the MSAP flap represents a valid solution for local defect coverage in the popliteal region, providing a sufficient amount of tissue and meeting the "like-with-like" criteria.

Combined use of lower medial thigh perforator (LMTP) flap and pedicled medial sural artery perforator flap (MSAP) for lateral knee defects coverage after sarcoma resection: A case report and literature review of soft tissue defect around knee reconstruction

Reconstruction of knee defects still represents a challenge for reconstructive surgeons. After an extensive resection, the primary aim is to reach a stable result, while maintaining a good range of motion and aesthetic unity. The use of pedicled perforator-based flaps makes it possible to achieve these goals. Many are the flaps that can be used in this region, and the pedicle medial sural artery perforator (mSAP) flap is considered among one of the first-choice techniques. The purpose of this case report is to describe for the first time the use of pedicled mSAP flap to cover a lateral knee defect. A 79-year-old patient underwent extensive excision of sarcoma on the lateral side of the left knee, with removal of distal portion of the vastus lateralis muscle and portion of the biceps femoris tendon. The resulting defect from the excision measured 10 cm × 10 cm. To cover the postero-inferior part of the defect we decided to use a mSAP flap, with a skin paddle 10 cm × 5 cm, which was tunneled posteriorly to the popliteal artery and vein in order to reach the affected site. We then used a lower medial thigh perforator (pLMT) flap with a 15 cm × 5 cm skin paddle, rotated by 90° in a propeller fashion to cover the antero-superior portion of the defect. The decision to use two flaps was justified by the fact we wanted to close the donor areas with direct suturing for a better aesthetic result. The post-operative course was regular with only a small wound dehiscence that had healed by secondary intention. At 6 months postoperatively, the patient showed a complete active range of motion of the knee joint and absolute aesthetic satisfaction with flaps donor site and knee shape. A review of literature is also provided, with a specific focus on the different procedures for soft tissue defects reconstruction around the knee. According to our experience, the pedicle of the MSAP flap may be safely used as an additional reconstructive option for lateral knee defects.

Outcomes of the Pedicled Medial Sural Artery Perforator Flap for Soft Tissue Reconstruction Around the Knee: When to Use It and How to Look After It

Introduction  The medial gastrocnemius flap is an established workhorse flap to cover proximal leg defects due to its reliability and simplicity to raise. However, it has the disadvantage of being bulky, requiring a skin graft for coverage, and is associated with loss of muscle power. The pedicled medial sural artery perforator (MSAP) flap has gained popularity as a reconstructive alternative for defects of the lower extremities. We present a case series of pedicled MSAP flaps for reconstructing defects around the knee as an alternative to the medial gastrocnemius flap. Materials and Methods  A consecutive series of patients with proximal leg defects following trauma, osteomyelitis, burns, and chronic wounds were included. A hand-held Doppler was used to map out the MSAPs. Defects were reconstructed using pedicled MSAP flaps, preserving the nerve supply to the gastrocnemius muscle. Patient outcomes were recorded, including their Enneking scores postreconstruction. Results  A total of 10 pedicled flaps was performed to reconstruct defects around the knee joint between October 2017 and November 2018. All the patients were discharged 1 week postoperatively, and rehabilitation consisted of graduated flexion in a knee brace by means of controlled passive mobilization. Three out of the ten patients developed complications: one patient developed flap congestion, one developed epidermolysis of the tip of the flap, and the other patient had partial necrosis of the skin paddle. The average Enneking score was 29 out of 35. Conclusion  The pedicled MSAP flap is a good reconstructive option for proximal leg defects as it is associated with lower donor site morbidity and provides an aesthetically pleasing reconstruction.

"Reverse tensor fascia latae perforator flap for reconstruction of knee defect: Anatomic study by computed tomographic angiography and a case report"

BACKGROUND

Reverse anterolateral thigh perforator (ALTp) pedicle flap can be used to reconstruct perigenicular defect thanks to the anastomoses between the descending branch of the lateral circumflex femoral artery (LCFA) and the perigenicular network. In a few cases, however, patients do not present any ALTp. We hypothesized that, in such cases, an adjacent perforator, the tensor fascia latae perforator (TFLp), emerging from the LCFA ascending branch, could be used instead. To assess the feasibility of this technique, a radiological study was conducted. A first patient was treated using this option.

METHODS

Sixty lower limb computed tomography were analyzed. The first treated patient was a 50-years-old man suffering from a 5-mm chronic bone exposure and osteomyelitis. Other reconstructive options were not indicated since he presented a multiscarry leg, severe arteriopathy, and no ALTp. A TFLp flap was raised, and the LCFA ascending and descending branches were dissected in continuity. After ligation of the LCFA, the blood flow reversed in the descending branch to irrigate the flap through the ascending branch.

RESULTS

A TFL perforator was observed in all the cases of the radiological study. The LCFA branching pattern was compatible with achieving a reverse TFL perforator flap in 43 cases (72%). The average pedicle length was 32 cm (22-38 cm). In the first clinical case, the flap covered the defect easily. After three months, the patient showed no evidence of infection recurrence and recovered a painless walk.

CONCLUSION

The reverse TFLp flap can be a suitable option for perigenicular reconstruction.

The superior lateral genicular artery flap for reconstruction of knee and proximal leg defects

Reconstruction of defects around the knee region requires thin and pliable skin. The superior lateral genicular artery (SLGA) flap provides an excellent alternative to muscle-based flaps. The anatomy and the surgical techniques of the SLGA flap were reviewed and the results of cases using the SLGA flap for coverage of knee and proximal leg defects were analyzed. SLGA flaps were performed in two cases and followed up for at least 6 months. Twelve articles on the use of the SLGA flap were also identified. A review of 39 cases showed that the mean diameter of the perforator supplying the skin of the flap was 1.04 mm, while the mean diameter of the SLGA at its origin was 1.78 mm. The mean length of the pedicle measured from the origin of the popliteal artery was 7.44 cm. The average dimensions of the flap were 14.8×6.6 cm with primary closure of the donor site in 61.5% of cases. Of these cases, 38.5% were due to trauma, 23.1% were post-burn complications, 12.8% were defects after resection of tumors, and 10.3% were for ulcers post-bursectomy. The most common complication was flap tip necrosis. All studies reported favorable outcomes with complete wound healing.

Outcomes of the gastrocnemius flap performed by orthopaedic surgeons in salvage revision knee arthroplasty

Introduction: The gastrocnemius myofascial flap is used to manage soft-tissue defects over the anterior aspect of the knee in the context of a patient presenting with a sinus and periprosthetic joint infection (PJI) or extensor mechanism failure. The aim of this study was twofold: firstly, to evaluate the outcomes of gastrocnemius flaps performed by appropriately trained orthopaedic surgeons in the context of PJI and, secondly, to evaluate the infection-free survival of this patient group. Patients and methods: We retrospectively reviewed 30 patients who underwent gastrocnemius flap reconstruction during staged revision total knee arthroplasty for prosthetic joint infection (PJI). All flaps were performed by an orthopaedic surgeon with orthoplastics training. Patients had a mean age of 68.9 years (range 50-84) and were followed up for a mean of 50.4 months (range 2-128 months). A total of 29 patients (97 %) were categorized into Musculoskeletal Infection Society (MSIS) local extremity grade 3 (greater than two compromising factors), and 52 % of PJIs were polymicrobial. The primary outcome measure was flap failure, and the secondary outcome measure was recurrent infection. Results: Flap survival was 100 % with no failures or early returns to theatre for flap problems such as necrosis or haematoma. Overall infection-free survival during the study period was 48 % (13 of 27 infected cases). Using limb salvage as the outcome, 77 % (23 of 30 patients) retained the limb. Infection recurrence occurred in 48 % (10 patients) in the type B3 cohort and 67 % (4 patients) in the type C3 cohort ( p = 0.65 ). Conclusions: The surgical technique for a gastrocnemius myofascial flap is reliable and reproducible when performed by appropriately trained orthopaedic surgeons, even in high-risk groups. However, the risks of recurrent infection and amputation remain high within our series due to poor host and extremity factors.

The Versatility of the Pedicled Medial Sural Artery Perforator Flap: From Simple to Its Chimeric Pattern and Clinical Experience with 37 Cases

BACKGROUND

Defects in the knee area, popliteal fossa region, and upper third of the lower extremity can pose a challenge for reconstructive plastic surgeons. The purpose of this article is to report the authors' experience with the use of the pedicled medial sural artery perforator flap in its simple and chimeric form for reconstruction of defects in three different regions: knee, popliteal fossa, and proximal lower leg.

METHODS

From April of 2018 to April of 2019, 37 patients (29 men and eight women) with a mean age of 51 years (range, 18 to 78 years) underwent reconstruction with 37 pedicled medial sural artery perforator flaps. All flaps were harvested as pedicled perforator flaps in conventional or chimeric fashion and were based on one or two perforators. The defect locations included the knee (18 cases), popliteal fossa (seven cases), and proximal lower leg (12 cases). The cause of reconstruction was trauma in 22 patients (59 percent), tumor in 10 patients (27 percent), and donor-site closure of free medial sural artery perforator in five patients (14 percent).

RESULTS

The flap sizes varied from 3.5 × 5 cm to 5 × 10 cm. All but one flap, which showed distal tip necrosis, survived completely after surgery. The donor sites were all closed primarily. Minor complications included flap dehiscence (two cases) and minor wound infection delaying the healing process (four cases). All complications were treated conservatively. Follow-up observations were conducted for 3 to 12 months, and all patients had good functional recovery with satisfactory cosmetic results.

CONCLUSION

The pedicled medial sural artery perforator flap can be considered an optimal method of reconstruction for covering defects not only in the knee area but also in the popliteal fossa and upper lower leg.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

The Effect of Medial Sural Artery Perforator Flap on Reconstruction of Soft Tissue Defects: A Meta-Analysis With Multiple Free Soft Flaps

BACKGROUND

With the gradual popularity of relatively novel medial sural artery perforator flap (MSAPF), robust studies are needed to compare the surgical outcomes of MSAPF versus multiple free soft flaps (MFSFs) to verify the advantages and disadvantages of MSAPF.

METHODS

The authors searched PubMed, Web of Science, EMBASE, Cochrane Library, Chinese BioMedical Literature Database (CBM), and China National Knowledge Infrastructure (CNKI) until September, 2020, to identify studies that compared surgical outcomes of MSAPF and MFSFs. Two authors followed the PRISMA guidelines, individually extracted the data and performed the quality assessments. Survival rate of flaps, satisfaction degree of patients in recipient and donor site, skin grafting, and morbidity of recipient and donor site were evaluated.

RESULTS

A total of 441 cases from 7 studies were included in our analysis. No significant differences were found regarding survival rate of flaps, recipient morbidity, and recipient satisfaction degree between the 2 groups. However, MSAPF group was significantly superior to MFSFs group in terms of skin grafting, morbidity, and satisfaction degree of donor site.

CONCLUSION

Our meta-analysis showed that the MSPAF and MFSFs groups were similar in terms of survival rate of flaps, recipient morbidity, and recipient satisfaction degree. Medial sural artery perforator flap group was superior to MFSFs group in terms of morbidity and satisfaction degree of donor site. The results may prove that MSAPF is gaining popularity for a reason and is a good choice for repairing soft tissue defects.

New Technique for the Proximal Leg Reconstruction: Medial Sural Artery-Based Cross-leg Flap

Reconstruction of the lower extremity, especially the proximal lower leg, is known to be a challenge for reconstructive surgeons. When there is extensive vascular damage, the use of local flaps and microsurgical methods will be limited, so there are few reconstructive options available. We want to define the use of medial sural artery-based cross-leg flap for the reconstruction of the proximal lower leg. A 51-year-old male had a soft tissue defect on the proximal leg region because of a gun-shot injury. We observed that there was no chance of a local flap as a result of CT angiography. We considered free flap to be risky because of extensive vascular damage and medial sural artery-based cross-leg flap was planned. 12*20-cm-sized medial sural artery-based cross-leg flap was elevated from the contralateral leg and adapted to the defect without tension. Medial sural artery-based flap is mostly used as a vascular island for the reconstruction of knee defects. However, its use as a cross-leg flap has not been found in the literature. We believe that it is a safe option to consider in challenging cases such as after flap failure or patients not suitable for a free flap.

[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.

Advancements in Reconstructive Surgery Broaden Opportunities for Salvage of the Injured Lower Extremity

Advancements in microsurgery have made lower extremity reconstruction possible even after major soft tissue loss or tibial nerve disruption. There is an ongoing paradigm shift in the indications for amputation versus salvage and in flap selection protocols for different areas of the lower extremity. Initial evaluation, patient selection, triage, and timing of reconstruction are essential factors that can influence functional and aesthetic outcomes. The emergence of perforator flaps and the application of new concepts such as free-style flaps, propeller perforator flaps, thinning of free flaps, and supermicrosurgery have provided reconstructive surgeons with many techniques to decrease donor-site morbidity and improve outcomes. This includes options for reconstruction on extremities with single or no adequate runoff vessels. We present a review of the major advancements in reconstructive surgery for salvage of the traumatic lower extremity.