{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T10:51:36Z","timestamp":1785408696317,"version":"3.56.0"},"reference-count":21,"publisher":"Vilnius University Press","issue":"1","license":[{"start":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T00:00:00Z","timestamp":1784678400000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["AML"],"abstract":"<jats:p>Lumbrical muscles are essential for the coordination and precise movement of the hand; although anatomical variation in these muscles is rare, they can have significant clinical consequences, especially when they affect the carpal tunnel. Accessory heads of lumbrical are infrequent, typically unilateral, and often asymptomatic. However, when these variants pass through the carpal tunnel, they may decrease the tunnel\u2019s volume, compress the median nerve, and contribute to the onset of Carpal Tunnel Syndrome (CTS). We present a rare case of a bilateral Accessory Head of the first Lumbrical Muscle (AHFL) discovered during a routine cadaveric dissection of a 65-year-old male. Recognizing such variations is crucial in clinical practice, as abnormal muscle tissue can complicate the diagnosis and surgical treatment of CTS. Preoperative imaging and thorough intraoperative examination can assist in identifying these variants, thus enhancing surgical planning and reducing complications.<\/jats:p>","DOI":"10.15388\/amed.2026.33.1.15","type":"journal-article","created":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T05:35:26Z","timestamp":1784698526000},"page":"177-183","source":"Crossref","is-referenced-by-count":0,"title":["Bilateral Accessory Head of First Lumbrical: Anatomical Insight and Surgical Implications during Carpal Tunnel Release"],"prefix":"10.15388","volume":"33","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-6588-361X","authenticated-orcid":false,"given":"Anand","family":"Verma","sequence":"first","affiliation":[{"id":[{"id":"https:\/\/ror.org\/029mnbn96","id-type":"ROR","asserted-by":"publisher"}],"name":"All India Institute of Medical Sciences Bhubaneswar"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-3436-6913","authenticated-orcid":false,"given":"Karan","family":"Kumar","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/029mnbn96","id-type":"ROR","asserted-by":"publisher"}],"name":"All India Institute of Medical Sciences Bhubaneswar"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Madhumita","family":"Patnaik","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/029mnbn96","id-type":"ROR","asserted-by":"publisher"}],"name":"All India Institute of Medical Sciences Bhubaneswar"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Manisha R.","family":"Gaikwad","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/029mnbn96","id-type":"ROR","asserted-by":"publisher"}],"name":"All India Institute of Medical Sciences Bhubaneswar"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9494-9468","authenticated-orcid":true,"given":"Praveen Kumar","family":"Ravi","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/029mnbn96","id-type":"ROR","asserted-by":"publisher"}],"name":"All India Institute of Medical Sciences Bhubaneswar"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"6097","published-online":{"date-parts":[[2026,7,22]]},"reference":[{"key":"ref0","unstructured":"Standring S. 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Natl J Clin Anat. 2025;14(1):41-43. doi:10.4103\/NJCA.NJCA_169_24","DOI":"10.4103\/NJCA.NJCA_169_24"},{"key":"ref4","doi-asserted-by":"publisher","unstructured":"Gabr\u00edkov\u00e1 K, Kachl\u00edk D, Belbl M, Kunc V. An accessory muscle belly or an accessory muscle head? An unusual arrangement of muscles in the anterior compartment of the forearm. Surg Radiol Anat. 2023;45(3):271-275. doi:10.1007\/s00276-023-03084-0","DOI":"10.1007\/s00276-023-03084-0"},{"key":"ref5","doi-asserted-by":"publisher","unstructured":"Nayak SR, Rathan R, Chauhan R, Krishnamurthy A, Prabhu LV. An additional muscle belly of the first lumbrical muscle. Cases J. 2008;1(1):103. doi:10.1186\/1757-1626-1-103","DOI":"10.1186\/1757-1626-1-103"},{"key":"ref6","doi-asserted-by":"publisher","unstructured":"Clarnette J, Shunmugam M, Rezaian P, McLean J. The Effect of the Lumbrical Muscle Position on Carpal Tunnel Syndrome. 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J Hand Surg Am. 2014;39(1):149-155. doi:10.1016\/j.jhsa.2013.06.029","DOI":"10.1016\/j.jhsa.2013.06.029"},{"key":"ref10","doi-asserted-by":"publisher","unstructured":"Khizer Hussain Afroze M, Sangeeta M, Varalakshmi K.L. Revisiting the Morphological Variations in Lumbricals of Hand. Acad Anat Int. 2020;6(1):43-48. doi:10.21276\/aanat.2020.6.1.10","DOI":"10.21276\/aanat.2020.6.1.10"},{"key":"ref11","doi-asserted-by":"publisher","unstructured":"Mehta HJ, Gardner WU. A study of lumbrical muscles in the human hand. Am J Anat. 1961;109:227-238. doi:10.1002\/aja.1001090302","DOI":"10.1002\/aja.1001090302"},{"key":"ref12","doi-asserted-by":"publisher","unstructured":"Mehta V. Bilateral bipartite origin of the posterior belly of digastric muscle: a clinico-anatomical appraisal. Anatomy. 2011;5(1):44-47. doi:10.2399\/ana.09.042","DOI":"10.2399\/ana.09.042"},{"key":"ref13","unstructured":"Sawant PJ. Study of Variant Lumbricals of Hans in 50 Donated Cadavers. International Journal of Preclinical & Pharmaceutical Research. 2015;6(2):70-73."},{"key":"ref14","doi-asserted-by":"publisher","unstructured":"Koizumi M, Kawai K, Honma S, Kodama K. Anomalous lumbrical muscles arising from the deep surface of flexor digitorum superficialis muscles in man. Ann Anat. 2002;184(4):387-392. doi:10.1016\/S0940-9602(02)80062-0","DOI":"10.1016\/S0940-9602(02)80062-0"},{"key":"ref15","doi-asserted-by":"publisher","unstructured":"Nam Y-S, Lee DY, Yoon JS, Lim S, Eo S. Accessory first lumbrical muscle within the carpal tunnel: a case report. Case Reports Plast Surg Hand Surg. 2024;11(1):2351130. doi:10.1080\/23320885.2024.2351130","DOI":"10.1080\/23320885.2024.2351130"},{"key":"ref16","doi-asserted-by":"publisher","unstructured":"\u00d6ten E, U\u011fur L. 3D volumetric evaluation of the diagnosis and severity of carpal tunnel syndrome using MRI. J Clin Neurosci. 2022;97:82-86. doi:10.1016\/j.jocn.2022.01.007","DOI":"10.1016\/j.jocn.2022.01.007"},{"key":"ref17","doi-asserted-by":"publisher","unstructured":"B\u00f6rekci A, Selahi \u00d6, Tanriverdi N, Osama M, Bat\u0131rel HA, Kontaytekin KB, Berikol G, \u00c7eliko\u011flu E, \u00d6zcan-Ek\u015fi EE, Ek\u015fi M\u015e. Accessory Hand Muscles Over the Transverse Carpal Ligament: An Obstacle in Carpal Tunnel Surgery. World Neurosurg. 2023;170:e402-e415. doi:10.1016\/j.wneu.2022.11.045","DOI":"10.1016\/j.wneu.2022.11.045"},{"key":"ref18","doi-asserted-by":"publisher","unstructured":"Smith-Paredes D, Vergara-Cereghino ME, Lord A, Moses MM, Behringer RR, Bhullar B-AS. Embryonic muscle splitting patterns reveal homologies of amniote forelimb muscles. Nat Ecol Evol. 2022;6(5):604-613. doi:10.1038\/s41559-022-01699-x","DOI":"10.1038\/s41559-022-01699-x"},{"key":"ref19","doi-asserted-by":"publisher","unstructured":"Soldado-Carrera F, Vilar-Coromina N, Rodr\u00edguez-Baeza A. 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