{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,3]],"date-time":"2026-06-03T17:13:47Z","timestamp":1780506827992,"version":"3.54.1"},"reference-count":48,"publisher":"Georg Thieme Verlag KG","issue":"04","license":[{"start":{"date-parts":[[2026,1,8]],"date-time":"2026-01-08T00:00:00Z","timestamp":1767830400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Rofo"],"published-print":{"date-parts":[[2026,4]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>The intrinsic muscles of the hand (IMH) include the thenar muscles, hypothenar muscles, lumbrical muscles, dorsal interosseous muscles (DIOM), and ventral interosseous muscles (VIOM). The thenar muscles consist of the abductor pollicis brevis (APB), opponens pollicis (OPP), flexor pollicis brevis (FPB), and adductor pollicis (ADP). The hypothenar muscles comprise the abductor digiti minimi (ADM), flexor digiti minimi (FDM), and opponens digiti minimi (ODM). Numerous anatomical variants of the IMH exist \u2013 including the accessory abductor digiti minimi (aADM), adductor hypothenar muscle, extensor digitorum brevis manus (EDBM), lumbrical muscle (LM) variants, and accessory flexor digitorum superficialis of the index finger. Although these variants are common, they can cause symptoms, especially in nerve compression syndromes such as carpal tunnel syndrome (CTS) from median nerve (MN) compression or Guyon\u2019s canal syndrome from ulnar nerve (UN) compression. Knowledge of these variants and their imaging characteristics facilitates understanding of related pathologies and contributes to improved therapeutic management. These muscle variants are diagnosed using high-resolution ultrasound (US) and magnetic resonance imaging (MRI).<\/jats:p>\n                  <jats:p>This review provides a comprehensive overview of the normal anatomy of the IMH, their anatomical variants, and their imaging features. High-resolution US is the primary modality for studying the IMH, while high-field 3T MRI offers excellent spatial resolution and contrast.<\/jats:p>\n                  <jats:p>Understanding the anatomy and anatomical variants of the IMH is essential for accurately assessing both normal and pathological conditions using US and MRI.<\/jats:p>","DOI":"10.1055\/a-2761-4259","type":"journal-article","created":{"date-parts":[[2026,1,9]],"date-time":"2026-01-09T00:45:35Z","timestamp":1767919535000},"page":"457-478","source":"Crossref","is-referenced-by-count":2,"title":["Imaging of the intrinsic muscles of the hand \u2013 part I: high-resolution ultrasound and 3T MRI appearance of symptomatic anatomical variants"],"prefix":"10.1055","volume":"198","author":[{"given":"Hicham","family":"Bouredoucen","sequence":"additional","affiliation":[{"name":"Imaging and Medical Informatics, Geneva University Hospitals, Geneva, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sana","family":"Boudabbous","sequence":"additional","affiliation":[{"name":"Imaging and Medical Informatics, Geneva University Hospitals, Geneva, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pierre-Alexandre","family":"Poletti","sequence":"additional","affiliation":[{"name":"Imaging and Medical Informatics, Geneva University Hospitals, Geneva, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lokmane","family":"Taihi","sequence":"additional","affiliation":[{"name":"Medical Imaging, University Hospital Saint-Luc, Brussels, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"194","published-online":{"date-parts":[[2026,1,8]]},"reference":[{"issue":"01","key":"ref1","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1016\/j.hcl.2011.09.006","article-title":"Anatomy and function of the thenar muscles","volume":"28","author":"S Gupta","year":"2012","journal-title":"Hand Clin"},{"issue":"03","key":"ref2","doi-asserted-by":"publisher","first-page":"361","DOI":"10.1016\/s0363-5023(87)80004-7","article-title":"Anatomy of the thenar branch of the median nerve","volume":"12","author":"J Mumford","year":"1987","journal-title":"J Hand Surg Am"},{"issue":"03","key":"ref3","first-page":"461","article-title":"The double anastomotic innervation of thenar muscles","volume":"109","author":"D Harness","year":"1971","journal-title":"J Anat"},{"issue":"03","key":"ref4","doi-asserted-by":"publisher","first-page":"397","DOI":"10.1002\/ca.22855","article-title":"Anatomical insights of the palmaris brevis muscle for clinical procedures of the hand","volume":"30","author":"DH Kim","year":"2017","journal-title":"Clin Anat"},{"issue":"01","key":"ref5","doi-asserted-by":"publisher","first-page":"19","DOI":"10.1016\/j.hcl.2011.09.003","article-title":"Anatomy and function of the hypothenar muscles","volume":"28","author":"JA Pasquella","year":"2012","journal-title":"Hand Clin"},{"issue":"03","key":"ref6","doi-asserted-by":"publisher","first-page":"500","DOI":"10.1016\/j.jhsa.2004.01.006","article-title":"Anatomic study of variations of hypothenar muscles and arborization patterns of the ulnar nerve in the hand","volume":"29","author":"K Murata","year":"2004","journal-title":"J Hand Surg Am"},{"issue":"94","key":"ref7","doi-asserted-by":"publisher","first-page":"e122","DOI":"10.15557\/jou.2023.0021","article-title":"Ultrasound of the palmar aspect of the hand: normal anatomy and clinical applications of intrinsic muscles imaging","volume":"23","author":"R Picasso","year":"2023","journal-title":"J Ultrason"},{"key":"ref8","doi-asserted-by":"crossref","first-page":"S295","DOI":"10.1148\/radiographics.20.suppl_1.g00oc18s295","article-title":"Abnormal signal intensity in skeletal muscle at MR imaging: patterns, pearls, and pitfalls","volume":"20","author":"DA May","year":"2000","journal-title":"Radiographics"},{"issue":"01","key":"ref9","doi-asserted-by":"publisher","first-page":"189","DOI":"10.1148\/radiology.210.1.r99ja35189","article-title":"Uniform fat suppression in hands and feet through the use of two-point Dixon chemical shift MR imaging","volume":"210","author":"M Maas","year":"1999","journal-title":"Radiology"},{"issue":"03","key":"ref10","doi-asserted-by":"crossref","first-page":"228","DOI":"10.1177\/028418519503600303","article-title":"Muscle edema in MR imaging of neuromuscular diseases","volume":"36","author":"H Schedel","year":"1995","journal-title":"Acta Radiol"},{"issue":"01","key":"ref11","first-page":"123","article-title":"The two heads of flexor pollicis brevis","volume":"95","author":"MH DAY","year":"1961","journal-title":"J Anat"},{"issue":"06","key":"ref12","doi-asserted-by":"publisher","first-page":"862","DOI":"10.1016\/s0363-5023(85)80162-3","article-title":"The palmaris brevis profundus. 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