‘Perineal keystone design perforator island flap’ for perineal and vulval reconstruction

Outcomes of the keystone perforator island flap for oncologic reconstruction of the back

BACKGROUND

Coverage of posterior trunk defects after tumor resection can be challenging due to the intricate anatomy. The keystone perforator island flap (KPIF) provides coverage of the defect without the need for distant flap coverage or microsurgery, matches the recipient's skin color and contour, and requires a short operative time.

METHODS

A retrospective review of all oncological back reconstructions with KPIF was performed at our institution. The patient comorbidities and surgical outcomes were collected.

RESULTS

A total of 17 patients underwent 20 KPIF (15 single and 2 double) for back reconstruction. Surgical indications were sarcoma (n = 12) and melanoma (n = 5). The mean age at surgery was 47.3 years (SD 23.3). The flaps were located in the upper back (n = 8), paraspinal (n = 4), middle back (n = 6), and lower back (n = 2). The average wound size after sarcoma and melanoma excision were 231.6 ± 297.4 and 156.7 ± 269.7 cm² , respectively. Four patients required an additional planned skin graft and one patient underwent a simultaneous myocutaneous latissimus dorsi flap. The mean operative time, including tumor resection, was 256 min (SD 118). The median length-of-hospital stay was 3 days (Q1-3: 1-6.5) and the median follow-up time was 35.3 months (Q1-3: 13.3-53.1). All flaps survived with minor surgical complications which included hematoma (n = 1), surgical site infection requiring debridement (n = 1), superficial wound dehiscence (n = 1), cellulitis (n = 1), and seroma (n = 1). The reconstructions were successful in 100% of patients.

CONCLUSIONS

The KPIF is a reliable and safe option for reconstruction of oncological back defects with minimal perioperative complications. This flap option avoids the use of free flaps and myocutaneous flaps for moderate-sized back defects.

Keystone Flap as a Reconstructive Option for selected areas; A Prospective Study

OBJECTIVE

A very few flaps would be described as versatile as the Keystone Flap. There is an increasing demand for coverage of defects in lower limb due to traumatic defects as well as other parts of the body. Keystone flap is one of its kind, which is simple and easy to perform. It is a safe option for conditions where microsurgery may not be a viable option. The relative simplicity of this flap makes it a to go option at many places.

METHODS

A prospective study was developed from October 2017 to December 2019 at SMS Hospital, Jaipur. We assessed the size of the flap, operation time, average hospital stay and the complications. Perforators over the leg were Doppler marked preoperatively over which the flap was raised.

RESULTS

50 patients were taken into the study. 30 key stone flaps were done to cover lower limb defects, 10 flaps were done for upper limb defects and the remaining 10 were for trunk defects. The average intraoperative time from skin incision to final suture was 50 min (range 20-90 min). The largest defect covered by keystone flap in our series measured 50 × 20 cm and the smallest defect covered was 8 × 4 cm. The average hospital stay was 3 days. We observed partial flap necrosis in 2 cases which required skin grafting. 3 other cases had wound infection leading to wound dehiscence, which required secondary suturing. The overall success rate was 95%.

CONCLUSION

The Keystone flap being a versatile flap with its qualities of replacing "like with like", easy to perform, use of local tissue, good vascularity and a low complication rate makes it an excellent flap for a variety of defects. The KeyStone flap allows reconstruction in a single stage and is a relatively easy and fast technique for the beginner as well as the experienced surgeon. We believe it should be incorporated more into a surgeons practice.

Keystone Flaps: Physiology, Types, and Clinical Applications

The keystone perforator flap (KPF) was first introduced in 2003 by Behan et al for use in reconstruction after skin cancer excision. Since its initial description, KPF use has been expanded to complex defects of various etiologies and disorders throughout the body. At its most basic, the KPF is a perforator-type flap designed with a 1:1 flap-to-defect width ratio. Keystone perforator flaps are specifically raised on pedicles arising from musculocutaneous or fasciocutaneous perforator vessels. Major advantages of the KPF derive from the maintenance of perforator vascular territories, perforosomes, permitting increased flap viability. In turn, this allows for more aggressive undermining in sites away from perforators when greater skin mobilization is necessary. Furthermore, the KPF is relatively easy to perform leading to shorter operative times and no postoperative monitoring period. There are basically 4 different types of keystone flaps in order of increasing undermining and disturbance of underlying fascia. These different classifications of KPFs may be used in different anatomical locations over the entire body based on skin laxity and defect size/depth. Numerous advancements and modifications have been documented adapting the KPF to specific conditions, including myelomeningoceles, and scrotal and lower eyelid defects. The purpose of this article is to provide an organized review of the KPF with emphasis on different classifications, applications, and limitations as well as an overview of the surgical technique. We have additionally included a discussion on KPF physiology and review of current literature.

Successful application of modified keystone flaps following skin tumor ablation

Skin cancer and precancerous skin lesions cause significant soft-tissue defects following tumor ablation. Recently, keystone flaps have gained popularity due to their simplicity, versatility, and reliability.We evaluated the efficacy of modified keystone flaps for soft-tissue reconstruction following skin tumor ablation in 2 medical centers.We reviewed the medical records of patients who received modified keystone flaps following the removal of skin tumors from January 2017 to December 2017. The diagnosis, site, flap size, and complications were recorded.Forty-one modified keystone flaps were evaluated, and the wound dimensions ranged from 1 cm × 1 cm to 18 cm × 9.5 cm, with an average size of 9.8 cm × 6.4 cm. With our selection strategy, specific modified keystone flaps were designed for the soft-tissue defects. The flap dimensions ranged from 2.2 cm × 1 cm to 26 cm × 10 cm, with an average size of 14.3 cm × 7.5 cm. Two patients developed minor wound dehiscence (4.9%), and 1 patient developed partial flap loss (2.4%), but all of these patients healed after local wound care without the need for surgical intervention.Our selection strategy for modified keystone flaps is a feasible and reliable option for reconstruction following skin tumor excision.

Keystone Flap: Overcoming Paradigms

Background:

The physiology and geometry of the keystone flap (KF) are the main factors that support its development. This study reports our experience using the KF and proposes the concept of pedicular area.

Methods:

A prospective cohort study was conducted from October 2014 to December 2016, in which 112 KF procedures were performed with an average follow-up time of 10 months. The conclusions drawn from clinical observations were compared with the findings of a literature review.

Results:

One hundred twelve flaps were performed in 89 patients (45 men and 44 women) with an average age of 64 years (range, 3–89 years). The flap survival rate was 100%. The term pedicular area (PA) was coined to describe a flap segment that remains attached to its bed without vascular detriment and whose location can be randomly selected. In this study, the PA could be reduced up to a 10%, which means that over 90% of each flap was dissected without any harm.

Conclusions:

The KF is a safe, cost-effective technique with better results when compared with other reconstructive procedures. Although research is still needed to better understand the physiological adaptations of KF, the clinical evidence supports its use in many reconstructive scenarios.

Keystone Flaps in Urethroplasty: Reconstruction in a Complex Case of Panurethral Stricture Disease

Panurethral strictures are a surgical challenge for a reconstructive urologist more so in situations where local tissue for reconstruction is deficient. Two-stage urethroplasty is the preferred option in such cases. In some complex stricture diseases where patients are not willing for multiple procedures, permanent perineal urethrostomy can give a good functional outcome. Keystone flaps have been used as a simple and effective method of wound closure in other areas of the body that would otherwise have required complex flap closure and skin grafting. We describe, for the first time, a case of inflammatory panurethral stricture disease complicated by Fournier gangrene with extensive penile, scrotal, and perineal skin deficit managed with a perineal urethrostomy, with the help of keystone design perforator island flaps with successful outcome.

The Keystone Flap in Dermatology: Clinical Experience with 18 Patients

INTRODUCTION AND OBJECTIVES

The keystone flap is a fasciocutaneous flap supplied by perforating arteries. It is used in dermatology to repair surgical defects in areas with low skin extensibility (the upper and lower limbs and the back). We review the clinical experience gained with keystone flap reconstruction at our hospital and report on the surgical outcomes.

MATERIAL AND METHODS

Descriptive retrospective study of patients with malignant skin tumors on the lower limbs who underwent keystone flap reconstruction.

RESULTS

Eighteen patients (mean age, 77.83 years) underwent keystone flap reconstruction using the Behan technique in 17 cases and the modified Moncrieff technique in one. Basal cell carcinomas accounted for 38.8% of the tumors excised, squamous cell carcinomas 33.3%, and malignant pigmented tumors 27.7%. Cardiovascular risk factors were observed in 72.2% of patients. Minor complications occurred in 38.8% of patients, and there were no cases of partial or total flap necrosis.

CONCLUSIONS

We consider the keystone flap to be a good alternative to other flaps and grafts for the surgical reconstruction of lower limb defects. The success rate was high, and the cosmetic and functional outcomes were good.

Evolving Concepts of Keystone Perforator Island Flaps (KPIF): Principles of Perforator Anatomy, Design Modifications, and Extended Clinical Applications

BACKGROUND

Keystone flaps have demonstrated growing clinical applications in reconstructive surgery in the past decade. This article highlights flap modifications and their versatility for clinical applications and management of complex defects.

METHODS

A retrospective chart review was conducted of consecutive patients undergoing keystone flap reconstruction at the authors' institution from January of 2012 to December of 2014. Patient demographics, indications, and operative and postoperative details were abstracted.

RESULTS

Forty-two keystone flaps were performed in 36 patients. Indications included malignant melanoma (n = 14), soft-tissue sarcoma (n = 12), benign pathologic conditions (e.g., exposed hardware, enterocutaneous fistula, tissue necrosis) (n = 6), and nonmelanoma skin cancer (n = 4). Twenty-eight percent received neoadjuvant irradiation, and 70 percent of these were for sarcoma. Locoregional adjunct flaps were performed in eight patients. The deep fascia was nearly completely in a circumferential manner in 18 of 36 patients (50 percent), in 92 percent of the sarcoma reconstructions, and located mainly in the lower extremity. Average defect size was 215 cm (range, 4 to 1000 cm). Average defect size was 474 cm and 35.8 cm after sarcoma and malignant melanoma resection, respectively. Average flap size was 344 cm (range, 5 to 1350 cm). Ninety percent of cases had flap sizes exceeding the traditional 1:1 ratio. There was no flap loss or partial necrosis. Mean time to mobilization was 1.8 days, and mean hospital length of stay was 6.8 days.

CONCLUSIONS

Keystone flaps offer an excellent versatile tool for reconstructive surgeons. Fundamental principles behind the vascular basis of the keystone flap and its modifications permit their greater utility in complex wounds in the settings of large oncologic resections, irradiation, and trauma.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.