{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,5]],"date-time":"2026-03-05T11:56:58Z","timestamp":1772711818978,"version":"3.50.1"},"reference-count":27,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,3,1]],"date-time":"2026-03-01T00:00:00Z","timestamp":1772323200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background\/Objectives: Skin and soft tissue defects of the head and neck are common challenges in plastic surgery and require reconstruction strategies tailored to defect size and depth. This study aimed to evaluate the clinical application and outcomes of the hemi-keystone flap (KF) technique and its modifications for head and neck reconstruction. Methods: A retrospective cohort study was conducted on 50 patients (36 males, 14 females; aged 9\u201392 years) who underwent hemi-KF reconstruction between September 2020 and March 2024. Data were collected on defect characteristics, flap design, surgical time, complications, scar outcomes, and follow-up duration. Scar outcomes were assessed using the Patient and Observer Scar Assessment Scale (POSAS). Results: The mean defect and flap sizes were 4.68 \u00b1 4.14 cm2 and 11.79 \u00b1 16.69 cm2, respectively. Single original hemi-KFs were used in 60% of cases, and double hemi-KFs in 32%. The mean flap-surgery duration was 29.04 \u00b1 14.56 min. Partial wound dehiscence occurred in 6% of cases. The mean follow-up period was 6.34 \u00b1 5.43 months. The mean POSAS scores were 15.30 \u00b1 3.59 (patient) and 17.12 \u00b1 3.70 (observer), indicating favorable scar outcomes and patient satisfaction. Conclusions: The hemi-KF technique and its modifications are reliable and versatile options for head and neck reconstruction, offering favorable functional and aesthetic outcomes.<\/jats:p>","DOI":"10.3390\/jcm15051888","type":"journal-article","created":{"date-parts":[[2026,3,2]],"date-time":"2026-03-02T10:24:34Z","timestamp":1772447074000},"page":"1888","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Retrospective Analysis of 50 Hemi-Keystone Flap Head and Neck Reconstructions with Scar Assessment"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-0203-3059","authenticated-orcid":false,"given":"Wonseok","family":"Cho","sequence":"first","affiliation":[{"name":"Department of Plastic and Reconstructive Surgery, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul 03181, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eun A","family":"Jang","sequence":"additional","affiliation":[{"name":"Department of Plastic and Reconstructive Surgery, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul 03181, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9998-8722","authenticated-orcid":false,"given":"Kyu Nam","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Plastic and Reconstructive Surgery, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul 03181, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e14167","DOI":"10.1097\/MD.0000000000014167","article-title":"Relaxed skin tension line\u2013oriented keystone\u2013designed perforator island flaps considering the facial aesthetic unit concept for the coverage of small to moderate facial defects","volume":"98","author":"Yoon","year":"2019","journal-title":"Medicine"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1864","DOI":"10.1097\/SCS.0000000000007359","article-title":"Use of keystone flaps in consideration of the facial aesthetic subunit concept as an alternative reconstructive option for nasal defect coverage","volume":"32","author":"Lee","year":"2021","journal-title":"J. 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