Keystone flaps: physiology, types, and clinical applications. Ann Plast Surg. 2019;83:226-231. [PMID: 31135505 DOI: 10.1097/sap.0000000000001854]

Clinical effects of different types of flaps selected according to local conditions in the treatment of diabetic foot defects

BACKGROUND

The repair of diabetic foot defects (DFD) is a major challenge in clinical practice. The purpose of this study was to investigate the difference in clinical efficacy of different flap techniques in repairing DFD wounds, and to compare the difference in clinical efficacy of anterolateral thigh perforator flap (ALTP) in repairing DFD and non-DFD.

METHODS

This study is a retrospective clinical study of different types of flap reconstruction in patients with DFD admitted to our hospital from January 2010 to December 2021. A total of 40 patients with DFD and 43 patients with non-DFD were included in this study. Detailed preoperative basic information, intraoperative details, postoperative complications and long-term follow-up results were collected.

RESULT

The comorbidities, wound infection and wound duration of DFD group were more serious than those of non-DFD group. In addition, the incidence of complications was higher in DFD group, the wound healing time was longer, the aesthetic evaluation, the functional recovery rate of ankle joint and the sensory recovery effect of flaps were worse.

CONCLUSION

In this study, it is concluded that different flap techniques can obtain better clinical efficacy in repairing DFD wounds. Compared with non-DFD wounds, the postoperative risk of DFD wounds using free ALTP flaps is higher, but the risk can be reduced by reasonable preoperative vascular examination. Free flap can deal with various irregular wounds and provide more options for clinical repair.

LEVEL OF EVIDENCE

III, Case-control study.

The Keystone Flap: A Game Changer That Promises New Horizons in Reconstructive Surgery

BACKGROUND

Since its first description emerged in 2003, the keystone flap has garnered the attention of the international scientific community due to its high safety profile and the suitably low complication rate associated with the reconstructive process.

MATERIALS AND METHODS

In this study, data were obtained from the performance of 72 keystone flaps to cover soft-tissue defects after the excision of neoplastic processes, excisions, and injuries occurring in polytrauma. The study was conducted in the Department of Plastic Surgery, "Bagdasar-Arseni" Emergency Hospital, Bucharest, and two plastic surgeons in the department performed the surgical procedures.

RESULTS

The statistical analysis revealed a remarkably low complication rate (3.22%), excellent functional and esthetic results, and a short hospitalization time. No intraoperative complications were identified during this study. The degree of satisfaction obtained after reconstructive surgery was exceptionally high, with a score of 9.47 on a 10-point rating scale (0 = poor results, 10 = excellent results) from the patient's perspective and 9.51 out of 10 for the surgical team.

CONCLUSIONS

The keystone flap is the optimal solution for reconstructing soft-tissue defects of variable sizes and shapes. It is associated with a low length of hospitalization, a low complication rate, and high patient satisfaction.

Versatility of the Keystone Design Perforator Island Flaps in Resurfacing Soft Tissue Defects

Background  The keystone design perforator island flap (KDPIF) is unique among local flaps because of its high potential for adaptation. We describe our experience with the use of the keystone flap for the reconstruction of a variety of defects in different regions of the body concerning its versatility, surgical outcomes, complications, postoperative pain, operative time, and esthetic outcomes. Methods  A prospective observational study was conducted at our institute from June 2021 to June 2023 where the use of KDPIFs in resurfacing soft tissue defects of different etiopathogenesis was evaluated and the data were analyzed. Results  Forty-four patients were included in the study with soft tissue defects of various etiologies and at different locations. The largest flap raised was 18 × 10 cm and the smallest was 4 × 2 cm. The average intraoperative time for completion of the procedure was 74.86 minutes (range: 45-120 minutes). The success rate of flap survivability was 95.45% with two patients having total flap loss necessitating another reconstructive option. Partial flap dehiscence which healed secondarily was observed in two patients. Postoperative pain showed a significant fall of 83.7% from baseline and 82.9% of cases were extremely satisfied with the esthetic outcome. Conclusion  The keystone flap is a valuable reconstructive tool in the armamentarium of a plastic surgeon. It is technically reproducible, suitable to be done in resource-limited settings, and provides contiguous tissue with good vascularity and fewer complications.

Keystone Flap for Closure of Skin Cancer Defects on the Upper Extremity

Background: We sought to examine the efficacy of the Keystone Design Perforator Island Flap (KDPIF) for the reconstruction of skin cancer excision defects isolated to the upper extremity. In particular, to examine the size of defects repaired and the complications associated with the keystone flap procedure isolated to the upper extremity. Methods: This is a retrospective chart review including all patients older than 18 years of age who received a KDPIF procedure between February 2013 and February 2019 for the oncologic reconstruction of skin cancer defects isolated to the upper extremities by a single surgeon. All procedures were done according to the original description by Behan. Results: A total of 32 patients, 18 (56%) male and 14 (44%) female, received 35 keystone flaps between February 2013 and February 2019. The mean age of the males and females was 70.5 and 79.7 years of age, respectively. Thirty-five lesions suspicious for cancer were excised and 14 (40%) basal cell carcinoma (BCC), 11 (31%) squamous cell carcinoma (SCC), 9 (26%) melanoma, and 1 (3%) actinic keratoses diagnoses were histopathologically determined. Skin defect excisions varied from 3.53 cm2 to 31.42 cm2. No intraoperative or postoperative complications occurred. Conclusions: The keystone flap is a successful versatile flap procedure with a low or absent complication rate for the reconstruction of skin cancer excision defects of various locations (eg arm, hand, elbow, forearm, shoulder, and wrist), cancer pathologies, and sizes on the upper extremity. When needed, a Doppler may successfully identify adequate perforating blood vessels for the relatively larger flaps.

The Keystone Perforator Island Flap: Review of Utility and Versatile Clinical Applications

Background

The keystone perforator island flap (KPIF) was described almost a decade ago. However, this flap has only recently been recognized for its advantages in various clinical applications in plastic surgery. A better understanding of the versatility of KPIFs can help promote the widespread adoption of this technique for complex wounds in various anatomical regions.

Methods

A retrospective chart review was conducted of patients undergoing KPIFs from December 2018 to March 2022 at the authors' home institution. The indications, surgical approaches, patient characteristics, and outcomes were extracted for review and analysis.

Results

A total of 12 patients (ages 13-86 years) underwent reconstruction with KPIFs for oncologic and nononcologic defects. By anatomic region, three cases involved the upper back, six involved the lumbosacral region, one involved the perineum, and two involved the midfoot. Half of the patients (n = 6) had failed previous attempts at wound closure. The mean defect size was 13.8 × 10.0 cm for the upper back lesions, 13.7 × 4.8 for the lumbosacral defects, and 3.5 × 2.0 for the metatarsal wounds. Median follow-up time for all patients was 7.5 months (IQR: 4-10.5). On follow-up, there was 100% flap survival.

Conclusion

KPIFs are a simple, safe, and suitable option for reconstructive closure of defects in many anatomical areas, including wounds complicated by previous failed closure attempts, with low complication risk profile.

Results of prophylactic simple fasciocutaneous advancement in the initial management of acute ankle fractures with high risk of operative wound complication

Ankle fracture is the third most prevalent fracture in older adults. Wound dehiscence is the most frequent complication. Our objective is to determine the operative wound complication rate in patients with unstable ankle fracture in whom a prophylactic simple fasciocutaneous advancement was used.

METHODS

Prospective registry of patients with unstable ankle fracture, in whom a prophylactic fasciocutaneous advancement was performed between August 2020 and July 2021. Demographic variables, time spent in performing the flap, cost of osteosynthesis, minor and major complications of the surgical wound, readmission or reoperation were registered.

RESULTS

42 older adults with ankle fracture were included. Median age 69 (60-94). 31% diabetics and 21.5% active smokers. A 40% trimalleolar fracture pattern. There were 7% of superficial complications of the surgical wound. No major complications, no reoperations.

CONCLUSIONS

Prophylactic fasciocutaneous advancement at the beginning of traumatological surgery is technically simple, reproducible, cheap and with low complications.

LEVEL OF EVIDENCE

Level IV, cross-sectional study.

Subcutaneous pedicled propeller flap for reconstructing the large eyelid defect due to excision of malignancies or trauma

Large eyelid defect after excision of malignancies or trauma is difficult to reconstruct due to special structure and function of the eyelid. In this study, we aimed to present the outcomes of subcutaneous pedicled propeller flap for reconstructing the large eyelid defect after excision of malignancies or trauma. A retrospective review of patients diagnosed with eyelid defect due to excision of malignancies or trauma, and undergoing subcutaneous pedicled propeller flap for reconstructing the large eyelid defect, was conducted at our hospital. The clinical data were collected and analyzed. A total of 15 patients were included in the cases series. Nine patients were diagnosed with basal cell carcinoma, 3 patients with epidermoid carcinoma, and 3 patients with trauma. All the defects were successfully covered with this designed flap. There was no flap necrosis in all the cases. No functional problems were observed in all of the cases. At long-term postoperative follow-up, the average score of patients’ satisfaction was good. This subcutaneous pedicled propeller flap is a feasible alternative technique for reconstructing the large eyelid defect after excision of malignancies or trauma. This flap option could avoid the use of free flaps for large defect.

The Keystone Flap: A Multi-centric Experience in Elderly Patients Treatment

Soft tissue reconstruction in elderly patients must be rapid and reliable. The keystone island flap (KF) offers an effective solution, with low complication rates and quick recovery. This multi-centric study aims to show authors' experience with KFs in treating soft tissue defects of trunk and limbs. Patients with soft tissue defects suitable for KF reconstruction were recruited from March 2019 to December 2019. Active inflammation and previous surgeries in the same region were considered exclusion criteria. Complications that occurred during follow-up were recorded, and their incidence pattern was assessed with the Fisher test. Seventy-two patients with mean age of 76.2 years old were selected. They presented lesions in torso (46; 63.9%) or in upper (4; 5.6%) or lower (22; 30.6%) limb regions. Fifteen (20.8%) wounds were non-oncologic lesions, and the others were oncologic lesions, mostly non-melanoma skin cancers. KF type I was carried out in 42 (58.3%) cases, KF type II-A in 13 (18%) cases, double opposed type III KF in 16 (22.2%) patients, and 1 (1.4%) case required partial flap's undermining (IV KF). Mean post-operative recovery period was 4.3 days (range, 1-9 days). Post-surgical complications occurred in 15 (20.8%) cases, 7 (9.7%) of them were considered major complications. No statistically significant difference in complications' incidence, nor among different surgical sites nor among KF types, was registered. Reconstructive surgeons have to adapt their work to elderly patients. The KF allows rapid operative times, low morbidity rates, and short post-operative recovery time, thus appearing as a feasible solution.

A comparative study for tension-reducing effect of Type I and Type II keystone perforator island flap in the human back

The keystone perforator island flap (KPIF) is popular in reconstructive surgery. However, despite its versatility, its biomechanical effectiveness is unclear. We present our experience of KPIF reconstruction in the human back and evaluate the tension-reducing effect of the KPIF. Between September 2019 and August 2020, 17 patients (51.82 ± 14.72 years) underwent KPIF reconstruction for back defects. In all cases, we measured wound tension at the defect and donor sites before and after KPIF reconstruction using a tensiometer. All defects occurred after complete excision of complicated epidermoid cysts and debridement of surrounding tissues. The defects were successfully covered with Type IIA KPIFs. All flaps survived, and there were no significant postoperative complications. The mean “tension change at the defect after Type I KPIF” and “tension change at the defect after Type II KPIF” were − 2.97 ± 0.22 N and − 5.59 ± 0.41 N, respectively, (P < 0.001). The mean “rate of tension change at the defect after Type I KPIF” and “rate of tension change at the defect after Type II KPIF” were − 36.54 ± 1.89% and − 67.98 ± 1.63%, respectively, (P < 0.001). Our findings confirm the stepwise tension-reducing effect of KPIF and clarify the biomechanics of this flap.

Reconstructing Complex Open Back Wounds with a Modified Minimal-Access Keystone Flap: A Case Report

CASE

A 61-year-old patient was referred 12 days postoperative with complex, infected, and dehisced paraspinal wound. After debridement and revision of hardware, deep dead space was eliminated through bilateral paraspinal muscle flap advancement. After hardware coverage, a large skin and tissue defect remained. The defect was reconstructed using a modified Keystone flap, eliminating the lateral cutaneous incision. Our patient healed without complication.

CONCLUSION

The modified Keystone flap is an option for reconstructing spinal wound defects, yielding excellent tissue coverage and advancement, grants additional flap advancement if necessary because of elimination of the lateral cutaneous incision, and an overall pleasing aesthetic result.

Keystone design perforator island flaps for coverage of non-oncological periarticular defects surrounded by the zone of injury

Objective

Periarticular defect coverage remains challenging because multi-vector tension forces affect wound tensile strength. This study presents our experience with keystone design perforator island flap (KDPIF) reconstruction of non-oncological periarticular defects surrounded by the zone of injury and describes the expanding versatility of KDPIF reconstruction for periarticular defects.

Methods

From June 2017 to July 2019, 12 patients aged 8 to 84 years underwent KDPIF reconstruction to cover periarticular defects. All defects resulted from non-oncological causes and were surrounded by the zone of injury. We reviewed the patients’ medical records and clinical photographs to collect and analyze clinical and operative data.

Results

The defect size ranged from 0.8 × 1.2 to 7 × 10 cm². The flap size ranged from 1.5 × 3 to 15 × 18 cm². All flaps survived completely. All patients showed favorable functional outcomes without significant limitation in joint range of motion during the follow-up period (range, 4–12 months). The mean observer scar assessment scale summary score and patient scar assessment scale total score were 17.667 ± 5.921 and 20.167 ± 6.478, respectively.

Conclusion

KDPIF reconstruction is a simple and effective surgical option for coverage of non-oncological periarticular defects surrounded by the zone of injury.

Keystone design perforator island flap in facial defect reconstruction

Facial defect coverage is a common subject in the field of reconstructive surgery. There are many methods for facial defect reconstruction, and reconstructive surgeons should choose the most appropriate method on a case-by-case basis to achieve both functional and aesthetic improvement. Among various options for facial reconstruction, the local flap technique is considered the best reconstructive modality to provide good tissue matches of color and texture, which is consistent with the ideal goal of reconstruction (replacement of like-with-like). Keystone design perforator island flap (KDPIF), devised by Behan in 2003, has been applied to various fields of reconstructive surgery in the past decade due to its design simplicity, robust vascular supply, and reproducibility. Several studies have reported KDPIF reconstruction of facial defects, such as large parotid defects, small-to-moderate nasal defects, and eyelid defects. However, KDPIF has been used relatively less in facial defects than in other body regions, such as the trunk and extremities. The purpose of this review is to provide an organized overview of facial KDPIF reconstruction including the classification of KDPIF, modifications, physiology, mechanism of flap movement, consideration of facial relaxed skin tension lines and aesthetics, surgical techniques, clinical applications, and precautions for successful execution of KDPIF reconstruction.

Smartphone Thermography for Lower Extremity Local Flap Perforator Mapping

BACKGROUND

 The versatile application of local perforator flaps for coverage throughout the lower extremity has already been well proven. Often a "free-style" approach has been used to design these flaps, as conventional imaging devices for perforator identification may be too expensive or unavailable. The recent adaptation of Smartphone thermal digital imaging may now prove to be a cheaper and more readily available means for identifying the requisite perforators that will sustain these local flaps.

METHODS

 Over the past year, a prospective study was undertaken of all patients having a local perforator flap for coverage of a lower extremity defect. Twenty-eight local perforator flaps involving all subtypes were utilized in 25 patients. Smartphone thermography was used in all patients preoperatively to identify preferable perforator or vascular network "hot spots" that allowed appropriate flap design. Intraoperative and postoperative monitoring was similarly done for all flaps to determine outcomes.

RESULTS

 All local perforator flaps were based on perforators identified using smartphone thermography. All flaps (23 or 82.1%) that the thermal digital image predicted 100% viability totally survived. Five flaps were predicted to have marginal viability, but two nevertheless survived completely while the others required only minor readjustments. Peninsular and keystone variety perforator flaps were those most commonly used.Thermography always facilitated making the correct decision as to whether a proximal- or distal-based peninsular flap would be superior. Subfascial elevation of cool spots in keystone flaps were found to be least likely to interfere with flap perfusion.

CONCLUSION

 Smartphone thermography is an inexpensive and expeditious means for identification of "hot spots" that is always used by us to ensure perfusion to lower extremity perforator local flaps. This is a complementary technique for their safer design, harvest, and subsequent monitoring in conjunction with more complex screening tools as indicated.