Evaluation of the Suprafascial Thin ALT Flap in Foot and Ankle Reconstruction

Surface to Perforator Index: Assessing the Importance of the Number of Perforators in Successful Harvesting of the Anterolateral Thigh Flap

BACKGROUND

 The use of perforator flaps has become more popular with improvement of surgical technique, technology, as well as understanding of microvascular anatomy. The selection of well-perfused angiosomes is critical to the successful outcome of patients undergoing free tissue transfer. The number of perforators that are needed is dependent upon the surface area of the flap being harvested; however, there have been no studies to assess the optimal surface area supplied by each perforator. We hypothesized that the smaller the surface area supplied by each perforator correlated with fewer flap-related complications in the harvesting of the anterolateral thigh (ALT) flap.

METHODS

 All ALT flaps harvested from 2015 to 2021 at our institution were retrospectively reviewed. The surface area of the flap harvested was calculated as A = πab, where a is the long radius and b is the short radius of the ellipse. The surface-perforator index (SPI) was calculated for each flap by dividing the surface area of the ALT flap by the number of perforators supplying the flap. Our primary outcomes were flap-related complications that included: partial flap loss, dehiscence, and venous congestion.

RESULTS

 A total of 106 patients were identified. Twenty-four patients (22.6%) developed perforator-related complications. An increasing SPI and SPI to body surface area were strongly associated with development of complications (adjusted odds ratio [95% confidence interval], adjusted p: 1.02 [1.01, 1.03], < 0.001and 1.23 [1.12, 1.42], p < 0.001). An SPI of greater than 150 cm2/perforator was associated with a higher probability of complications (p < 0.001).

CONCLUSION

 Flap-related complications are significantly related to the number of perforators supplying the flap. The smaller the surface area supplied by a single perforator correlates with significantly fewer flap-related complications. SPI is a new index that may be used as a predictive tool to aid in identifying flaps that may be more prone to complications in free tissue transfer.

Secondary Bony Defects after Soft Tissue Reconstruction in Limb-Threatening Lower Extremity Injuries: Does the Approach to Flap Elevation Matter?

BACKGROUND

 Limb-threatening lower extremity injuries often require secondary bone grafting after soft tissue reconstruction. We hypothesized that there would be fewer wound complications when performing secondary bone grafting via a remote surgical approach rather than direct flap elevation.

METHODS

 A retrospective cohort study was performed at a single Level 1 trauma center comparing complications after secondary bone grafting in patients who had undergone previous soft tissue reconstruction after open tibia fractures between 2006 and 2020. Comparing bone grafting via a remote surgical incision versus direct flap elevation, we evaluated wound dehiscence requiring return to the operating room as the primary outcome. Secondary outcomes were deep infection and delayed amputation.

RESULTS

 We identified 129 patients (mean age: 40 years, 82% male) with 159 secondary bone grafting procedures. Secondary bone grafting was performed via a remote surgical approach in 54% (n = 86) and direct flap elevation in 46% (n = 73) of cases. Wound dehiscence requiring return to the operating room occurred in one patient in the flap elevation group (1%) and none of the patients in the remote surgical approach. The odds of deep wound infection (OR, 1.77; p = 0.31) or amputation (OR, 1.43; p = 0.73) did not significantly differ between surgical approaches. No significant differences were found in complications between the reconstructive surgeon elevating and re-insetting the flap and the orthopaedic trauma surgeon performing the flap elevation and re-inset.

CONCLUSION

 Direct flap elevation for secondary bone grafting after soft tissue reconstruction for open tibia fractures did not result in more complications than bone grafting via a remote surgical approach. These findings should reassure surgeons to allow other clinical factors to influence the surgical approach for bone grafting.

Planes for Perforator/Skin Flap Elevation-Definition, Classification, and Techniques

BACKGROUND

 Elevation in different layers achieving thin flaps are becoming relatively common practice for perforator flaps. Although postreconstruction debulking achieves pleasing aesthetic results and is widely practiced, customized approach during elevation to achieve the ideal thickness will increase efficiency while achieving the best possible aesthetic outcome. Multiple planes for elevation have been reported along with different techniques but it is quite confusing and may lack correspondence to the innate anatomy of the skin and subcutaneous tissue.

METHODS

 This article reviews the different planes of elevation and aims to clarify the definition and classification in accordance to anatomy and present the pros and cons of elevation based on the different layers and provide technical tips for elevation.

RESULTS

 Five different planes of elevation for perforator flaps are identified: subfascial, suprafacial, superthin, ultrathin, and subdermal (pure skin) layers based on experience, literature, and anatomy.

CONCLUSION

 These planes all have their unique properties and challenges. Understanding the benefits and limits along with the technical aspect will allow the surgeon to better apply the perforator flaps.

Proximal peroneal perforator flap, cadaveric study, and clinical applications for shallow defect reconstructions

PURPOSE

Peroneal artery perforator offers a versatile range of microvascular tissue transfer methods from local flaps to vascularized osteocutaneous fibula flaps. It is one of the few flaps that can cover shallow defects that require thin and pliable skin paddles, such as in hands and feet (Han et al., 2018). The proximal region of the lower leg offers such flexible and thin flap compared to the middle and distal lower leg (Winters & de Jongh, 1999). However, the anatomy of the proximal peroneal artery perforator is relatively unknown in literature and its proximity to the common peroneal nerve (CPN) has not yet been studied. This study conducted a cadaveric study and put it in application into clinical settings.

METHODS

Twenty lower leg specimens were dissected according to the methods of clinical proximal peroneal artery perforator flap harvest. Perforators arising in the proximal lower leg area of between 20 and 40 percentile of fibular length were inspected. Perforator length, location from fibular head, course, and location of CPN were recorded. Clinical reconstruction cases using the proximal lateral lower leg were analyzed. Six patients between the ages of thirty and seventy were included. Five cases were due to trauma, and one from mass excision, but all required thin and pliable flaps for reconstructions in hands or feet. Flaps were designed concentrical oval shapes, and harvest was done similarly to cadaveric perforator dissection, but perforator dissection was done only up to the required pedicle length. Perforator length, flap size, thickness, and long-term complications were recorded.

RESULTS

Among 20 specimens, a total of 20 perforators were found in 18 cadavers (90%). Two specimens showed no perforators while two specimens showed multiple perforators. The perforators were located at an average of 101 mm from fibular head, with an average length of 55 mm ranging from 20 to 153 mm. The average size of perforator at origin was 2.0 mm, ranging from 1.0 to 3.6 mm. 45% showed septocutaneous course and 55% intramuscular course. Two out of 20 perforators were shown to arise from source vessels other than the peroneal artery. All clinical cases were successful without complications or debulking for contour shaping. Flap sizes ranged from 15 to 40 cm² . Largest flap width was 5 cm, and all donor sites were primarily closed without complications. One year of follow-up showed no complications.

CONCLUSION

Proximal peroneal artery perforator flap provides a reliable pedicle for a versatile tissue transfer. This study shows that the perforators of the proximal lateral lower leg often arise from vessels other than the peroneal artery, such as the anterior tibial artery or popliteal artery, as had been previously reported (Winters & de Jongh, 1999). Although the source vessel varies, perforator anatomy is at a safe distance from CPN. This variation of source vessels suggests a change in nomenclature to "proximal peroneal perforator flap." The clinical applications of this flap showed that it can be effectively used for reconstructions of shallow defects, such as in the hands and feet without secondary procedures for debulking.

From Esthetic Medicine to Optimizing Reconstructive Outcome: A Feasibility Trial on Secondary Refinement of Fasciocutaneous Anterolateral Thigh Flaps with Cryolipolysis

BACKGROUND

 Free adipocutaneous anterolateral thigh (ALT) flaps have evolved as workhorse flaps to reconstruct complex, multicompound defects. While coverage is safely achieved, flaps may remain bulky. As a standard of care, flaps are refined with liposuction, partial excision, or combination of both. Cryolipolysis is widely used for fat reduction in esthetic medicine. This pilot comparative study analyses whether cryolipolysis may serve as a safe alternative method to effectively reduce volume in fasciocutaneous flaps. Moreover, patients' satisfaction with the procedure is evaluated.

METHODS

 In this single-center, retrospective, interventional comparative cohort study, 10 patients with free subfascial ALT flaps for distal extremity reconstruction underwent cryolipolysis (60 minutes, -9°C). Circumference of the extremities and subcutaneous fat thickness were determined before (T1) and 12 weeks (T2) after cryolipolysis. Patient satisfaction was evaluated with a questionnaire of Likert's scale questions. Duration of hospital stay, intervention time, costs, and possible complications were analyzed and compared with surgical flap contouring (n = 12).

RESULTS

 All patients undergoing cryolipolysis were male, with a median age of 52 years without arterial disease-like state or deep vein thrombosis (DVT). At T2, a significant reduction of circumference of 1.8 ± 0.9 cm (p < 0.001) and subcutaneous fat layer of 7.7 ± 3.0 mm (p < 0.0001) was recorded. Overall, 90% of the patients were satisfied with the result. Cryolipolysis was well tolerated. One patient developed a second-degree frostbite which healed without further intervention. Cryolipolysis proofed to be as safe as surgical flap contouring. Hospital stay was significantly shorter (p < 0.01) and personal resources were spared when flap contouring was performed with cryolipolysis.

CONCLUSION

 This is a novel application of evolving body-contouring cryolipolysis from esthetic medicine into optimizing outcomes in reconstructive surgery. Cryolipolysis has been shown to be relatively safe and effective to reduce ALT's volume with high patients' satisfaction. This successful pilot study encourages further investigation with a prospective randomized control trial.

Evaluating Resource Utilization with Free or Pedicled Perforator Flaps in Distal Leg Reconstruction

Background The decision between local and free tissue coverage for distal lower leg defects has long been dictated by the location and size of defects. Recent reports of distal defects treated successfully with pedicled perforator flaps demonstrate equivalent clinical outcomes; however, the complication rate can be high. The goal of this study was to evaluate the cost equivalence of free versus pedicled perforator flap to assist decision-making and guide clinical care.

Methods The institutional database was searched for patients with acute injury over the distal lower extremity requiring free or pedicled perforator flap. Demographic, clinical, and total resource cost was gathered. Patients were matched to Gustilo–Anderson or Arbeitsgemeinschaft fur Osteosynthesefragen classification as well as size of defect and outcomes, and cost compared.

Results We have included 108 free flaps and 22 pedicled perforator flaps in the study. There was no difference in complication rate between groups. Free flaps had significantly more reoperations, required longer operative time, and had longer intensive care unit (ICU) care with higher cost of surgery and overall cost than pedicled flaps. When controlling for size of defect, surgical cost remained significantly different between groups (p = 0.013), but overall cost did not. Multivariable regression analysis indicated flap type to be the primary driver of cost of surgery, while body mass index elevated the total cost.

Conclusion Pedicled perforator flap coverage for small to medium-sized defects (< 70 cm2) is a viable and cost-effective option for distal lower leg soft tissue reconstruction after acute traumatic injury with similar clinical outcomes and shorter operative duration and ICU stay.