{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T07:27:42Z","timestamp":1774510062894,"version":"3.50.1"},"reference-count":15,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T00:00:00Z","timestamp":1774310400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Taiwan University Hospital, Bei-Hu Branch"},{"name":"Ministry of Science and Technology","award":["MOST 106-2314-B-002-180-MY3"],"award-info":[{"award-number":["MOST 106-2314-B-002-180-MY3"]}]},{"name":"Ministry of Science and Technology","award":["109-2314-B-002-114-MY3"],"award-info":[{"award-number":["109-2314-B-002-114-MY3"]}]},{"name":"Ministry of Science and Technology","award":["111-2314-B-002\u2013161"],"award-info":[{"award-number":["111-2314-B-002\u2013161"]}]},{"name":"Ministry of Science and Technology","award":["NSTC 113-2314-B-002-208-MY2"],"award-info":[{"award-number":["NSTC 113-2314-B-002-208-MY2"]}]},{"name":"Ministry of Science and Technology","award":["NSTC 113-2314-B-002-209-MY2"],"award-info":[{"award-number":["NSTC 113-2314-B-002-209-MY2"]}]},{"name":"Taiwan Society of Ultrasound in Medicine"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>This case highlights the diagnostic value of high-resolution ultrasonography in identifying postoperative injury of the posterior branch of the medial antebrachial cutaneous nerve (MABCN) following cubital tunnel surgery. A 45-year-old man developed localized pain, warmth, and paresthesia extending from the medial epicondyle to the proximal anterior forearm one month after ulnar nerve decompression and anterior transposition. Physical examination revealed focal allodynia and a positive Tinel sign. Because previous surgery may substantially alter the anatomical location of the surrounding nerves, electrodiagnostic localization can be technically challenging and less reliable. Ultrasonography therefore played a key diagnostic role. The images demonstrated the normal sonoanatomy of the MABCN and its anatomical relationship with the basilic vein and ulnar nerve, followed by pathologic findings of focal enlargement of the posterior branch adjacent to postoperative scar tissue. These imaging features, together with a positive sonographic Tinel sign, supported the diagnosis of localized nerve irritation. Ultrasound-guided hydrodissection using 5% dextrose and methylcobalamin resulted in marked clinical improvement, with the Visual Analog Scale pain score decreasing from 9 to 2. This case is particularly illustrative because postoperative injury of the MABCN may mimic recurrent cubital tunnel syndrome yet typically produces purely sensory symptoms confined to the medial elbow region. Targeted ultrasonographic evaluation can reveal subtle postoperative nerve pathology and guide effective ultrasound-guided intervention.<\/jats:p>","DOI":"10.3390\/diagnostics16070960","type":"journal-article","created":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T08:02:49Z","timestamp":1774339369000},"page":"960","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Ultrasound Evaluation and Treatment of Posterior Medial Antebrachial Cutaneous Nerve Injury Following Cubital Tunnel Release"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7511-9629","authenticated-orcid":false,"given":"Wei-Ting","family":"Wu","sequence":"first","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, Community and Geriatric Research Center, National Taiwan University Hospital, Bei-Hu Branch, Taipei 108206, Taiwan"},{"name":"Department of Physical Medicine and Rehabilitation, National Taiwan University College of Medicine, Taipei 100233, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7558-5651","authenticated-orcid":false,"given":"Ke-Vin","family":"Chang","sequence":"additional","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, Community and Geriatric Research Center, National Taiwan University Hospital, Bei-Hu Branch, Taipei 108206, Taiwan"},{"name":"Department of Physical Medicine and Rehabilitation, National Taiwan University College of Medicine, Taipei 100233, Taiwan"},{"name":"Center for Regional Anesthesia and Pain Medicine, Wang-Fang Hospital, Taipei Medical University, Taipei 110301, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2713-4071","authenticated-orcid":false,"given":"Levent","family":"\u00d6z\u00e7akar","sequence":"additional","affiliation":[{"name":"Department of Physical and Rehabilitation Medicine, Hacettepe University Medical School, Ankara 06100, Turkey"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2209","DOI":"10.1002\/jum.70010","article-title":"High-Resolution Ultrasound of Clinically Relevant Sensory Nerves of the Arm and the Forearm","volume":"44","author":"Zaottini","year":"2025","journal-title":"J. Ultrasound Med."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"757","DOI":"10.1016\/j.otsr.2020.03.003","article-title":"Curved skin incision for Ulnar nerve transposition in Cubital Tunnel Syndrome: Cadaveric and clinical study to avoid injury of medial cutaneous nerve","volume":"106","author":"Kwon","year":"2020","journal-title":"Orthop. Traumatol. Surg. Res."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"924","DOI":"10.5114\/aoms.2012.31623","article-title":"Dexamethasone and vitamin B12 synergistically promote peripheral nerve regeneration in rats by upregulating the expression of brain-derived neurotrophic factor","volume":"8","author":"Sun","year":"2012","journal-title":"Arch. Med. Sci. AMS"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"E45","DOI":"10.36076\/ppj\/2019.22.E45","article-title":"Vitamin B12 as a treatment for pain","volume":"22","author":"Buesing","year":"2019","journal-title":"Pain Physician"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"267","DOI":"10.1016\/0363-5023(89)90019-1","article-title":"Surgical anatomy of the medial antebrachial cutaneous nerve","volume":"14","author":"Masear","year":"1989","journal-title":"J. Hand Surg."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Li, H., Zhu, W., Wu, S., Wei, Z., and Yang, S. (2019). Anatomical analysis of antebrachial cutaneous nerve distribution pattern and its clinical implications for sensory reconstruction. PLoS ONE, 14.","DOI":"10.1371\/journal.pone.0222335"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"962","DOI":"10.1212\/WNL.44.5.962","article-title":"Peripheral nerve injury and causalgia secondary to routine venipuncture","volume":"44","author":"Horowitz","year":"1994","journal-title":"Neurology"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1016\/S0266-7681(85)80011-5","article-title":"Injury to the medial antebrachial cutaneous nerve during cubital tunnel surgery","volume":"10","author":"Dellon","year":"1985","journal-title":"J. Hand Surg."},{"key":"ref_9","unstructured":"Mackinnon, S.E., and Dellon, A.L. (2007). Surgery of the Peripheral Nerve, Thieme-Stratton Corp."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"193","DOI":"10.1097\/00003086-199108000-00027","article-title":"The Failed Ulnar Nerve Transposition: Etiology and Treatment","volume":"269","author":"Rogers","year":"1991","journal-title":"Clin. Orthop. Relat. Res."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"665","DOI":"10.1055\/s-2002-36497","article-title":"Medial brachial and antebrachial cutaneous nerve injuries: Effect on outcome in revision cubital tunnel surgery","volume":"18","author":"Sarris","year":"2002","journal-title":"J. Reconstr. Microsurg."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"25","DOI":"10.2106\/00004623-200101000-00004","article-title":"Complications of elbow arthroscopy","volume":"83","author":"Kelly","year":"2001","journal-title":"J. Bone Jt. Surg."},{"key":"ref_13","unstructured":"Yildiz, N., and Ardic, F. (2008). A rare cause of forearm pain: Anterior branch of the medial antebrachial cutaneous nerve injury: A case report. J. Brachial Plex. Peripher. Nerve Inj., 3."},{"key":"ref_14","unstructured":"Richards, R., and Regan, W. (1989). Medial epicondylitis caused by injury to the medial antebrachial cutaneous nerve: A case report. Can. J. Surg. J. Can. Chir., 32."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Chang, K.-V., Mezian, K., Na\u0148ka, O., Wu, W.-T., Lou, Y.-M., Wang, J.-C., Martinoli, C., and \u00d6z\u00e7akar, L. (2018). Ultrasound imaging for the cutaneous nerves of the extremities and relevant entrapment syndromes: From anatomy to clinical implications. J. Clin. Med., 7.","DOI":"10.3390\/jcm7110457"}],"container-title":["Diagnostics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2075-4418\/16\/7\/960\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T05:18:21Z","timestamp":1774502301000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2075-4418\/16\/7\/960"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,3,24]]},"references-count":15,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2026,4]]}},"alternative-id":["diagnostics16070960"],"URL":"https:\/\/doi.org\/10.3390\/diagnostics16070960","relation":{},"ISSN":["2075-4418"],"issn-type":[{"value":"2075-4418","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,3,24]]}}}