Background: The keystone flap is an effective technique for reconstructive surgery that restores the natural contour of the affected area and provides superior aesthetic results. This technique involves taking healthy skin and subcutaneous tissue from a nearby area and transplanting it to the site of the defect, creating a new skin area that meets the patient’s ideal outcome. We conducted a research project to objectively examine and evaluate the effectiveness and practicality of keystone flaps in clinical settings. Our two objectives were to analyze the characteristics of skin abnormalities on the body and to assess the surgical outcomes of using keystone flaps to repair defects. Methods: 40 patients with soft tissue defects throughout the body who underwent surgical treatment using keystone flap coverage at the Orthopedic and Plastic Surgery Center, Hue Central Hospital - Viet Nam. Results: The most common causes of soft tissue defects are infectious necrosis (35.0%), chronic ulcerative lesions (32.5%), trauma (17.5%), scar excision (12.5%), and other factors (2.5%). Flaps are primarily designed in Type I and Type III fashion. Our follow-up evaluation of the flaps after 3 - 6 months showed that the majority of cases achieved good results, with 37 out of 40 cases (92.5%) and 3 out of 40 cases (7.5%) categorized as fair. No significant complications were reported. Conclusion: The keystone island perforator flap is a modern method in plastic surgery that has proven to be a useful tool. The authors strongly recommend the use of the keystone technique as a safe, reliable, and feasible approach to covering soft tissue defects that vary in clinical characteristics.