Keystone Flaps for Coverage of Defects in the Posterior Neck and Lower Occipital Scalp: A Retrospective Clinical Study

How to Safely Use the Perforator-based Keystone Island Flap in the Scalp: Basal Cell Carcinoma of the Scalp With Local Invasion to Calvarium

Scalp reconstruction has always been a challenging problem for even the most experienced surgeon to provide good aesthetic and functional results. This is mainly because the scalp is less mobile and tight, requiring a much larger dissection for the size of the original defect. We hypothesized that the omega variant perforator-based keystone island flap at the subgaleal plane provides a versatile and easily reproducible reconstructive option for scalp reconstruction after wide skin cancer excision. We reviewed all patients who underwent reconstruction with the keystone flap or its modification to repair scalp defects following wide resection of skin cancer in the scalp abutting calvarium from May 2021 to July 2023. We designed the flap width 50% wider than original keystone flap design first introduced by Dr. Behan. We reconstructed medium- to large-sized scalp defects ranging from 2×2 to 5×5 cm 2 using an omega variant perforator-based keystone island flap. All patients were satisfied with the aesthetic outcomes without complications. Keystone flaps are a versatile option for reconstructing the scalp after cancer resection. This strategy obviates the need for skin grafting, myocutaneous flap or free flap after cancer removal in the scalp.

Reconstruction of cervical necrotizing fasciitis defect with the modified keystone flap technique: Two case reports

BACKGROUND

Cervical necrotizing fasciitis (CNF) is a rare, aggressive form of deep neck space infection with significant morbidity and mortality rates. Serial surgical debridement acts as the cornerstone of CNF treatment; however, it often results in defects requiring complex reconstructions.

CASE SUMMARY

We report two cases in which the keystone flap (KF) was used for CNF defect coverage: Case 1, an 85-year-old patient with CNF in the anterior neck, and Case 2, a 54-year-old patient with CNF in the posterior neck. Both patients received empirical intravenous antibiotic therapy and underwent serial debridement, enabling adequate wound preparation and stabilization. The final defect size measured 5.5 cm × 12 cm in Case 1 and 6 cm × 11 cm in Case 2. For defect coverage, we employed an 8 cm × 19 cm type II KF based on perforators from the superior thyroid artery in Case 1 and a 9 cm × 18 cm type II KF based on perforators from the transverse cervical artery in Case 2. Both flaps showed complete survival. No postoperative complications occurred in both cases, and favorable outcomes were observed at 7- and 6-month follow-ups in case 1 and 2, respectively.

CONCLUSION

We effectively treated CNF-associated defects using the KF technique; KF is viable for covering CNF defects in carefully selected cases.

Modified Keystone Perforator Island Flap for Tension-Reducing Coverage of Axillary Defects Secondary to Radical Excision of Chronic Inflammatory Skin Lesions: A Retrospective Case Series

Axillary defect coverage is often challenging after radical excision of chronic inflammatory skin lesions, such as complicated epidermoid cysts and hidradenitis suppurativa. This retrospective case series aims to demonstrate our experience with axillary reconstruction using the modified keystone perforator island flap (KPIF) technique, emphasizing its tension-reducing effects. All patients who presented for axillary reconstruction after radical excision of chronic inflammatory skin lesions between May 2019 and December 2020 were identified using the medical record database. Eleven patients ranging in age from 17 to 71 years underwent modified KPIF axillary reconstruction. Four types of modifications (modified type II KPIF, omega variation closure, Sydney melanoma unit modification, and hemi-KPIF) were used. All defects (size range, 2.5 × 3 cm² to 8 × 13 cm²) were successfully covered using these modified KPIF techniques. All flaps (size range, 3.5 × 3.5 cm² to 11 × 30 cm²) fully survived without complications. All patients exhibited favorable functional outcomes, and no cases of recurrence or limitations in joint range of motion were observed during the follow-up period (range, 4–5 months). Modified KPIF techniques may represent a reliable, effective alternative reconstructive modality for managing axillary defects.