{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T09:35:39Z","timestamp":1776936939149,"version":"3.51.4"},"reference-count":20,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T00:00:00Z","timestamp":1776902400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Background and Clinical Significance: Post-traumatic finger stiffness is frequently attributed to soft tissue adhesions; however, mechanical obstruction from occult osseous structures remains a rare but critical differential diagnosis in adults. Case Presentation: This report describes a 56-year-old female presenting with severe, refractory stiffness of the little finger eight months after a proximal phalanx fracture. Despite extensive conservative therapy, active and passive flexion at the proximal and distal interphalangeal joints remained locked in extension. While conventional radiographs demonstrated bony union, musculoskeletal ultrasonography (MSUS) revealed an occult protruding malunited fragment incarcerating the flexor tendons. Dynamic MSUS provided real-time evidence of mechanical impingement by demonstrating proximal muscle contraction without distal tendon excursion. Intraoperatively, initial soft tissue tenolysis failed to restore motion; further exploration guided by MSUS evidence successfully identified a sharp bone spike. Subsequent ostectomy resulted in immediate restoration of functional range of motion. This case underscores the limitations of static imaging in evaluating the dynamic gliding mechanism and highlights the valuable role of MSUS in identifying mechanical functional obstructions. Conclusions: Early sonographic evaluation should be considered for refractory post-traumatic stiffness to prevent prolonged, ineffective conservative care and to guide definitive surgical management.<\/jats:p>","DOI":"10.3390\/diagnostics16091260","type":"journal-article","created":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T08:11:14Z","timestamp":1776931874000},"page":"1260","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Sonographic Diagnosis of Flexor Tendon Incarceration by a Malunited Fracture Fragment: A Case Report"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6044-0276","authenticated-orcid":false,"given":"Yuan-Chen","family":"Chang","sequence":"first","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yu-Te","family":"Lin","sequence":"additional","affiliation":[{"name":"Department of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan"},{"name":"International Master Science Program in Reconstructive Microsurgery, Chang Gung University, Taoyuan 333, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9956-0347","authenticated-orcid":false,"given":"Yu-Hsuan","family":"Cheng","sequence":"additional","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan"},{"name":"Department of Physical Medicine and Rehabilitation, School of Medicine, College of Medicine, Taipei Medical University, Taipei 116, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e676","DOI":"10.5435\/JAAOS-D-18-00310","article-title":"Etiology, Evaluation, and Management Options for the Stiff Digit","volume":"27","author":"Catalano","year":"2019","journal-title":"J. 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Adhesions as a Component of the Trigger Finger: A Dynamic Sonographic Study. J. Hand Surg. Eur., 2021, 852\u2013856.","DOI":"10.1177\/1753193420969293"}],"container-title":["Diagnostics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2075-4418\/16\/9\/1260\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T08:37:16Z","timestamp":1776933436000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2075-4418\/16\/9\/1260"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,4,23]]},"references-count":20,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2026,5]]}},"alternative-id":["diagnostics16091260"],"URL":"https:\/\/doi.org\/10.3390\/diagnostics16091260","relation":{},"ISSN":["2075-4418"],"issn-type":[{"value":"2075-4418","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,4,23]]}}}