{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,15]],"date-time":"2026-04-15T23:22:33Z","timestamp":1776295353799,"version":"3.50.1"},"reference-count":17,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2021,11,19]],"date-time":"2021-11-19T00:00:00Z","timestamp":1637280000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Injury of the extensor hallucis longus (EHL) tendon is relatively rare, but surgical repair is necessary to prevent deformity and gait disturbance. Primary suturing is possible if the condition is acute, but not when it is chronic. The scar tissue between the ruptured ends is a proliferative tissue composed of fibroblasts and collagen fibers. Given the histological similarity to normal tendons, several studies have reported tendon reconstruction using scar tissue. Here, we report a reconstruction of a neglected EHL rupture using interposed scar tissue. A 54-year-old female visited our clinic with a weak extension of a big toe. She had dropped a knife on her foot a month prior, but did not go to hospital. The wound had healed, but she noted dysfunctional extension of the toe and increasing pain. Magnetic resonance imaging (MRI) revealed that EHL continuity was lost and that the proximal tendon stump was displaced toward the midfoot. Scar tissue running in the direction of the original ligament was observed between the ruptured ends. In the surgical field, the scar tissue formed a shape similar to the extensor tendon. Therefore, we performed tendon reconstruction using the interposed scar tissue. For the first 2 postoperative weeks, the ankle and foot were immobilized to protect the repair. Six weeks after surgery, the patient commenced full weight-bearing. At the 3-month follow-up, active extension of the hallux was possible, with a full range of motion. The patient did not feel any discomfort during daily life. Postoperative MRI performed at 1 year revealed that the reconstructed EHL exhibited homogeneously low signal intensity, and was continuous. The AOFAS Hallux Metatarsophalangeal-Interphalangeal scale improved from 57 to 90 points and the FAAM scores improved from 74% to 95% (the Activities of Daily Living subscale) and from 64% to 94% (the Sports subscale). Scar tissue reconstruction is as effective as tendon autografting or allografting, eliminates the risk of donor site morbidity and infection, and requires only a small incision and a short operative time.<\/jats:p>","DOI":"10.3390\/ijerph182212157","type":"journal-article","created":{"date-parts":[[2021,11,19]],"date-time":"2021-11-19T08:29:17Z","timestamp":1637310557000},"page":"12157","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Reconstruction of a Neglected, Extensor Hallucis Longus Tendon Rupture Using Interposed Scar Tissue: A Case Report and Literature Review"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4579-1008","authenticated-orcid":false,"given":"Woo-Jong","family":"Kim","sequence":"first","affiliation":[{"name":"Department of Orthopaedic Surgery, Soonchunhyang University Hospital Cheonan, 31, Suncheonhyang 6-gil, Dongam-gu, Cheonan 31151, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8777-0603","authenticated-orcid":false,"given":"Ki-Jin","family":"Jung","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Soonchunhyang University Hospital Cheonan, 31, Suncheonhyang 6-gil, Dongam-gu, Cheonan 31151, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9221-672X","authenticated-orcid":false,"given":"Hyein","family":"Ahn","sequence":"additional","affiliation":[{"name":"Department of Pathology, Soonchunhyang University Hospital Cheonan, 31, Suncheonhyang 6-gil, Dongam-gu, Cheonan 31151, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eui-Dong","family":"Yeo","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Veterans Health Service Medical Center, Seoul 05368, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hong-Seop","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Foot and Ankle Surgery, Nowon Eulji Medical Center, Eulji University, 68, Hangeulbiseok-ro, Nowon-gu, Seoul 01830, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sung-Hun","family":"Won","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Soonchunhyang University Hospital Seoul, 59, Daesagwan-ro, Yongsan-gu, Seoul 04401, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dhong-Won","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Konkuk University Medical Center, 120-1, Neungdong-ro, Gwangjin-gu, Seoul 05030, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jae-Young","family":"Ji","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology and Pain Medicine, Soonchunhyang University Hospital Cheonan, 31, Suncheonhyang 6-gil, Dongam-gu, Cheonan 31151, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sung-Joon","family":"Yoon","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Soonchunhyang University Hospital Cheonan, 31, Suncheonhyang 6-gil, Dongam-gu, Cheonan 31151, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2002-5021","authenticated-orcid":false,"given":"Yong-Cheol","family":"Hong","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Soonchunhyang University Hospital Cheonan, 31, Suncheonhyang 6-gil, Dongam-gu, Cheonan 31151, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"45","DOI":"10.1177\/1938640013514271","article-title":"Repair of acute extensor hallucis longus tendon injuries: A retrospective review","volume":"7","author":"Wong","year":"2014","journal-title":"Foot Ankle Spec."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"24","DOI":"10.1016\/S1067-2516(97)80006-3","article-title":"Extensor hallucis longus tendon injury: An in-depth analysis and treatment protocol","volume":"36","author":"Kass","year":"1997","journal-title":"J. Foot Ankle Surg. Off. Publ. Am. Coll. Foot Ankle Surg."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"162","DOI":"10.1177\/107110079601700308","article-title":"Spontaneous rupture of extensor hallucis longus tendon","volume":"17","author":"Mulcahy","year":"1996","journal-title":"Foot Ankle Int."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"490.e1","DOI":"10.1053\/j.jfas.2010.05.003","article-title":"Delayed rupture of the extensor hallucis longus and extensor digitorum communis tendons after breaching the anterior capsule with a radiofrequency probe during ankle arthroscopy: A case report","volume":"49","author":"Tuncer","year":"2010","journal-title":"J. Foot Ankle Surg."},{"key":"ref_5","first-page":"2050313X19841962","article-title":"Chronic extensor hallucis longus tendon rupture treated with double-bundle autograft of extensor hallucis capsularis: A case report","volume":"7","author":"Kurashige","year":"2019","journal-title":"SAGE Open Med. Case Rep."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1742","DOI":"10.2106\/00004623-199511000-00017","article-title":"Transmission of disease through transplantation of musculoskeletal allografts","volume":"77","author":"Tomford","year":"1995","journal-title":"JBJS"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"374","DOI":"10.1007\/s00402-004-0663-8","article-title":"Spontaneous healing process of a supraspinatus tendon tear in rabbits","volume":"124","author":"Hirose","year":"2004","journal-title":"Arch. Orthop. Trauma Surg."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"69","DOI":"10.1080\/00016470052943937","article-title":"Unfavorable effect of knee immobilization on Achilles tendon healing in rabbits","volume":"71","author":"Yasuda","year":"2000","journal-title":"Acta Orthop. Scand."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"582","DOI":"10.1177\/0363546506295939","article-title":"Reconstruction of chronic Achilles tendon rupture with the use of interposed tissue between the stumps","volume":"35","author":"Yasuda","year":"2007","journal-title":"Am. J. Sports Med."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1168","DOI":"10.2106\/JBJS.15.00865","article-title":"Direct repair of chronic Achilles tendon ruptures using scar tissue located between the tendon stumps","volume":"98","author":"Yasuda","year":"2016","journal-title":"JBJS"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"e22506","DOI":"10.1097\/MD.0000000000022506","article-title":"Direct reconstruction of chronic extensor digitorum longus tendon rupture using interposed scar tissue in the foot: A case report","volume":"99","author":"Yeo","year":"2020","journal-title":"Medicine"},{"key":"ref_12","unstructured":"Lezak, B., Wehrle, C.J., and Summers, S. (2021, September 15). Anatomy, bony pelvis and lower limb, posterior tibial artery. [Updated 8 August 2021], StatPearls, Available online: https:\/\/www.ncbi.nlm.nih.gov\/books\/NBK536981\/."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"186","DOI":"10.5435\/00124635-200505000-00005","article-title":"Nerve and tendon lacerations about the foot and ankle","volume":"13","author":"Thordarson","year":"2005","journal-title":"JAAOS J. Am. Acad. Orthop. Surg."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"633","DOI":"10.1007\/s00264-011-1391-7","article-title":"Adverse reactions and events related to musculoskeletal allografts: Reviewed by the World Health Organisation Project NOTIFY","volume":"36","author":"Hinsenkamp","year":"2012","journal-title":"Int. Orthop."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"467","DOI":"10.7547\/87507315-92-8-467","article-title":"Extensor hallucis longus tendon rupture repair using a fascia lata allograft","volume":"92","author":"Zielaskowski","year":"2002","journal-title":"J. Am. Podiatr. Med. Assoc."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"557","DOI":"10.1177\/107110079701800905","article-title":"Primary repair without augmentation for early neglected Achilles tendon ruptures in the recreational athlete","volume":"18","author":"Porter","year":"1997","journal-title":"Foot Ankle Int."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"364","DOI":"10.1007\/s001670000149","article-title":"Achilles tendon rupture: Experimental results on spontaneous repair in a sheep-model","volume":"8","author":"Bruns","year":"2000","journal-title":"Knee Surg. Sports Traumatol. Arthrosc."}],"container-title":["International Journal of Environmental Research and Public Health"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1660-4601\/18\/22\/12157\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T07:32:50Z","timestamp":1760167970000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1660-4601\/18\/22\/12157"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,11,19]]},"references-count":17,"journal-issue":{"issue":"22","published-online":{"date-parts":[[2021,11]]}},"alternative-id":["ijerph182212157"],"URL":"https:\/\/doi.org\/10.3390\/ijerph182212157","relation":{},"ISSN":["1660-4601"],"issn-type":[{"value":"1660-4601","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,11,19]]}}}