{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T22:32:26Z","timestamp":1769725946665,"version":"3.49.0"},"reference-count":36,"publisher":"Journal of Neurosurgery Publishing Group (JNSPG)","issue":"9","license":[{"start":{"date-parts":[[2025,9,1]],"date-time":"2025-09-01T00:00:00Z","timestamp":1756684800000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J Neurosurg Case Lessons"],"published-print":{"date-parts":[[2025,9,1]]},"abstract":"<jats:sec>\n                    <jats:title>BACKGROUND<\/jats:title>\n                    <jats:p>MRI-guided targeted fascicular biopsy has been a valuable technique for diagnosing idiopathic neuropathies. It has an 80% yield and a minor permanent morbidity rate of 5%.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>OBSERVATIONS<\/jats:title>\n                    <jats:p>A 48-year-old woman with a history of localized amyloidosis to the orbital muscle 2 years earlier presented with new neurological symptoms. Extensive evaluations including skin, muscle, and distal cutaneous nerve biopsies were negative, and empirical treatment trials did not improve her condition. An MRI-guided targeted biopsy of the right ulnar nerve in the distal arm was planned. During surgery, a medial triceps branch arising from the ulnar nerve was identified and was biopsied along with a neighboring fascicle of the ulnar nerve to the flexor carpi ulnaris. The pathology of the ulnar nerve fascicle but not the contiguous triceps branch showed amyloid (AL [kappa] subtype on mass spectroscopy). The patient was started on treatment.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>LESSONS<\/jats:title>\n                    <jats:p>The positive biopsy of the ulnar nerve fascicle allowed targeted treatment of the neural amyloidosis. While the negative biopsy of the triceps branch could be attributed to sampling error, it could also be due to the fact that this branch found within the ulnar nerve is thought to originate from the radial nerve.<\/jats:p>\n                    <jats:p>\n                      <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"uri\" xlink:href=\"https:\/\/thejns.org\/doi\/10.3171\/CASE25484\">https:\/\/thejns.org\/doi\/10.3171\/CASE25484<\/jats:ext-link>\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.3171\/case25484","type":"journal-article","created":{"date-parts":[[2025,9,1]],"date-time":"2025-09-01T23:49:12Z","timestamp":1756770552000},"source":"Crossref","is-referenced-by-count":0,"title":["Targeted biopsy of the ulnar nerve for amyloidosis with potential implications of a diagnostic and nondiagnostic biopsy: illustrative case"],"prefix":"10.3171","volume":"10","author":[{"given":"Christopher J. L.","family":"O\u2019Driscoll","sequence":"first","affiliation":[{"name":"Departments of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"P. James B.","family":"Dyck","sequence":"additional","affiliation":[{"name":"Departments of Neurology, Mayo Clinic, Rochester, Minnesota"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Robert J.","family":"Spinner","sequence":"additional","affiliation":[{"name":"Departments of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1754","reference":[{"issue":"3","key":"bib1","series-title":"Neurosurg Focus","first-page":"E9","article-title":"Targeted fascicular biopsy of the brachial plexus: rationale and operative technique","volume":"42","author":"Laumonerie","year":"2017","unstructured":"Laumonerie PCapek SAmrami KKDyck PJBSpinner RJ.Targeted fascicular biopsy of the brachial plexus: rationale and operative technique. Neurosurg Focus. 2017;42(3):E9."},{"issue":"5","key":"bib2","series-title":"Clin Anat","first-page":"616","article-title":"From targeted fascicular biopsy of major nerve to targeted cutaneous nerve biopsy: implementing clinical anatomy can catalyze a paradigm shift","volume":"31","author":"Marek","year":"2018","unstructured":"Marek THowe BMAmrami KKSpinner RJ.From targeted fascicular biopsy of major nerve to targeted cutaneous nerve biopsy: implementing clinical anatomy can catalyze a paradigm shift. Clin Anat. 2018;31(5):616-621."},{"issue":"8","key":"bib3","series-title":"Clin Anat","first-page":"1200","article-title":"Targeted nerve biopsy: a technique in evolution","volume":"31","author":"Marek","year":"2018","unstructured":"Marek TStone JJAmrami KKSpinner RJ.Targeted nerve biopsy: a technique in evolution. Clin Anat. 2018;31(8):1200-1204."},{"issue":"VideoSuppl1","key":"bib4","series-title":"Neurosurg Focus","first-page":"V7","article-title":"Targeted fascicular biopsy in a patient with prostate cancer","volume":"44","author":"Stone","year":"2018","unstructured":"Stone JJKaszuba MCSpinner RJ.Targeted fascicular biopsy in a patient with prostate cancer. Neurosurg Focus. 2018;44(VideoSuppl1):V7."},{"issue":"3","key":"bib5","series-title":"Neurosurg Focus","first-page":"E12","article-title":"Targeted fascicular biopsy of the sciatic nerve and its major branches: rationale and operative technique","volume":"39","author":"Capek","year":"2015","unstructured":"Capek SAmrami KKDyck PJBSpinner RJ.Targeted fascicular biopsy of the sciatic nerve and its major branches: rationale and operative technique. Neurosurg Focus. 2015;39(3):E12."},{"issue":"6","key":"bib6","series-title":"Br J Neurosurg","first-page":"727","article-title":"Muscle and nerve biopsy for the neurosurgical trainee","volume":"27","author":"Hart","year":"2013","unstructured":"Hart MGSantarius TTrivedi RA.Muscle and nerve biopsy for the neurosurgical trainee. Br J Neurosurg. 2013;27(6):727-734."},{"issue":"2","key":"bib7","series-title":"J Hand Surg Am","first-page":"232","article-title":"Nerve transfer to biceps muscle using a part of ulnar nerve for C5-C6 avulsion of the brachial plexus: anatomical study and report of four cases","volume":"19","author":"Oberlin","year":"1994","unstructured":"Oberlin CB\u00e9al DLeechavengvongs SSalon ADauge MCSarcy JJ.Nerve transfer to biceps muscle using a part of ulnar nerve for C5-C6 avulsion of the brachial plexus: anatomical study and report of four cases. J Hand Surg Am. 1994;19(2):232-237."},{"issue":"4","key":"bib8","series-title":"J Hand Surg Am","first-page":"633","article-title":"Nerve transfer to deltoid muscle using the nerve to the long head of the triceps, part II: a report of 7 cases","volume":"28","author":"Leechavengvongs","year":"2003","unstructured":"Leechavengvongs SWitoonchart KUerpairojkit CThuvasethakul P.Nerve transfer to deltoid muscle using the nerve to the long head of the triceps, part II: a report of 7 cases. J Hand Surg Am. 2003;28(4):633-638."},{"issue":"1","key":"bib9","series-title":"Clin Orthop Relat Res","first-page":"235","article-title":"A cadaveric study of ulnar nerve innervation of the medial head of triceps brachii","volume":"467","author":"Bekler","year":"2009","unstructured":"Bekler HWolfe VMRosenwasser MP.A cadaveric study of ulnar nerve innervation of the medial head of triceps brachii. Clin Orthop Relat Res. 2009;467(1):235-238."},{"issue":"3","key":"bib10","series-title":"J Hand Microsurg","first-page":"139","article-title":"Surgical implications of innervation pattern of the triceps muscle: a cadaveric study","volume":"10","author":"Chaware","year":"2018","unstructured":"Chaware PNSantoshi JAPatel MAhmad MRathinam BAD.Surgical implications of innervation pattern of the triceps muscle: a cadaveric study. J Hand Microsurg. 2018;10(3):139-142."},{"issue":"2","key":"bib11","series-title":"Indian J Orthop","first-page":"353","article-title":"Ulnar nerve innervation to triceps: a cadaveric study and a technical note on partial triceps to biceps transfer","volume":"53","author":"Jain","year":"2019","unstructured":"Jain DKAKumar STShetty N.Ulnar nerve innervation to triceps: a cadaveric study and a technical note on partial triceps to biceps transfer. Indian J Orthop. 2019;53(2):353-356."},{"issue":"8","key":"bib12","series-title":"Clin Anat","first-page":"1028","article-title":"Ulnar nerve innervation of the medial head of the triceps brachii muscle: a cadaveric study","volume":"26","author":"Loukas","year":"2013","unstructured":"Loukas MBellary SSY\u00fczba\u015fio\u011flu NShoja MMTubbs RSSpinner RJ.Ulnar nerve innervation of the medial head of the triceps brachii muscle: a cadaveric study. Clin Anat. 2013;26(8):1028-1030."},{"issue":"5","key":"bib13","series-title":"J Hand Surg Eur Vol","first-page":"430","article-title":"Abnormal innervation of the triceps brachii muscle by the ulnar nerve","volume":"35","author":"Miguel-P\u00e9rez","year":"2010","unstructured":"Miguel-P\u00e9rez MICombalia AArandes JM.Abnormal innervation of the triceps brachii muscle by the ulnar nerve. J Hand Surg Eur Vol. 2010;35(5):430-431."},{"issue":"1","key":"bib14","series-title":"Anat J Afr","first-page":"834","article-title":"Ulnar nerve contribution in the innervation of the triceps brachii muscle ulnar nerve to the triceps brachii","volume":"6","author":"Silva","year":"2017","unstructured":"Silva DLRBarros MPFreire TGSUlnar nerve contribution in the innervation of the triceps brachii muscle ulnar nerve to the triceps brachii. Anat J Afr. 2017;6(1):834-839."},{"issue":"6","key":"bib15","series-title":"Turk Neurosurg","first-page":"949","article-title":"Co-innervation of triceps brachii muscle with variant branch of ulnar nerve","volume":"28","author":"Develi","year":"2018","unstructured":"Develi S.Co-innervation of triceps brachii muscle with variant branch of ulnar nerve. Turk Neurosurg. 2018;28(6):949-953."},{"issue":"suppl 1","key":"bib16","series-title":"FASEB J","first-page":"lb23","article-title":"Variation of the radial nerve, ulnar nerve and axillary nerve in innervation of the three heads of the triceps brachii muscle","volume":"26","author":"Kauffman","year":"2012","unstructured":"Kauffman TOlinger ABorman WFisher C.Variation of the radial nerve, ulnar nerve and axillary nerve in innervation of the three heads of the triceps brachii muscle. FASEB J. 2012;26(suppl 1):lb23."},{"issue":"6","key":"bib17","series-title":"Clin Orthop Relat Res","first-page":"1887","article-title":"Ulnar nerve innervation of the triceps muscle: real or apparent? An anatomic study","volume":"471","author":"Pascual-Font","year":"2013","unstructured":"Pascual-Font AVazquez TMarco FSa\u00f1udo JRRodriguez-Niedenf\u00fchr M.Ulnar nerve innervation of the triceps muscle: real or apparent? An anatomic study. Clin Orthop Relat Res. 2013;471(6):1887-1893."},{"issue":"1","key":"bib18","series-title":"Clin Anat","first-page":"137","article-title":"Relationship between the ulnar nerve and the branches of the radial nerve to the medial head of the triceps brachii muscle","volume":"32","author":"Cho","year":"2019","unstructured":"Cho SHChung IHLee UY.Relationship between the ulnar nerve and the branches of the radial nerve to the medial head of the triceps brachii muscle. Clin Anat. 2019;32(1):137-142."},{"issue":"3","key":"bib1","series-title":"Neurosurg Focus","first-page":"E9","article-title":"Targeted fascicular biopsy of the brachial plexus: rationale and operative technique","volume":"42","author":"Laumonerie","year":"2017","unstructured":"Laumonerie PCapek SAmrami KKDyck PJBSpinner RJ.Targeted fascicular biopsy of the brachial plexus: rationale and operative technique. Neurosurg Focus. 2017;42(3):E9."},{"issue":"5","key":"bib2","series-title":"Clin Anat","first-page":"616","article-title":"From targeted fascicular biopsy of major nerve to targeted cutaneous nerve biopsy: implementing clinical anatomy can catalyze a paradigm shift","volume":"31","author":"Marek","year":"2018","unstructured":"Marek THowe BMAmrami KKSpinner RJ.From targeted fascicular biopsy of major nerve to targeted cutaneous nerve biopsy: implementing clinical anatomy can catalyze a paradigm shift. Clin Anat. 2018;31(5):616-621."},{"issue":"8","key":"bib3","series-title":"Clin Anat","first-page":"1200","article-title":"Targeted nerve biopsy: a technique in evolution","volume":"31","author":"Marek","year":"2018","unstructured":"Marek TStone JJAmrami KKSpinner RJ.Targeted nerve biopsy: a technique in evolution. Clin Anat. 2018;31(8):1200-1204."},{"issue":"VideoSuppl1","key":"bib4","series-title":"Neurosurg Focus","first-page":"V7","article-title":"Targeted fascicular biopsy in a patient with prostate cancer","volume":"44","author":"Stone","year":"2018","unstructured":"Stone JJKaszuba MCSpinner RJ.Targeted fascicular biopsy in a patient with prostate cancer. Neurosurg Focus. 2018;44(VideoSuppl1):V7."},{"issue":"3","key":"bib5","series-title":"Neurosurg Focus","first-page":"E12","article-title":"Targeted fascicular biopsy of the sciatic nerve and its major branches: rationale and operative technique","volume":"39","author":"Capek","year":"2015","unstructured":"Capek SAmrami KKDyck PJBSpinner RJ.Targeted fascicular biopsy of the sciatic nerve and its major branches: rationale and operative technique. Neurosurg Focus. 2015;39(3):E12."},{"issue":"6","key":"bib6","series-title":"Br J Neurosurg","first-page":"727","article-title":"Muscle and nerve biopsy for the neurosurgical trainee","volume":"27","author":"Hart","year":"2013","unstructured":"Hart MGSantarius TTrivedi RA.Muscle and nerve biopsy for the neurosurgical trainee. Br J Neurosurg. 2013;27(6):727-734."},{"issue":"2","key":"bib7","series-title":"J Hand Surg Am","first-page":"232","article-title":"Nerve transfer to biceps muscle using a part of ulnar nerve for C5-C6 avulsion of the brachial plexus: anatomical study and report of four cases","volume":"19","author":"Oberlin","year":"1994","unstructured":"Oberlin CB\u00e9al DLeechavengvongs SSalon ADauge MCSarcy JJ.Nerve transfer to biceps muscle using a part of ulnar nerve for C5-C6 avulsion of the brachial plexus: anatomical study and report of four cases. J Hand Surg Am. 1994;19(2):232-237."},{"issue":"4","key":"bib8","series-title":"J Hand Surg Am","first-page":"633","article-title":"Nerve transfer to deltoid muscle using the nerve to the long head of the triceps, part II: a report of 7 cases","volume":"28","author":"Leechavengvongs","year":"2003","unstructured":"Leechavengvongs SWitoonchart KUerpairojkit CThuvasethakul P.Nerve transfer to deltoid muscle using the nerve to the long head of the triceps, part II: a report of 7 cases. J Hand Surg Am. 2003;28(4):633-638."},{"issue":"1","key":"bib9","series-title":"Clin Orthop Relat Res","first-page":"235","article-title":"A cadaveric study of ulnar nerve innervation of the medial head of triceps brachii","volume":"467","author":"Bekler","year":"2009","unstructured":"Bekler HWolfe VMRosenwasser MP.A cadaveric study of ulnar nerve innervation of the medial head of triceps brachii. Clin Orthop Relat Res. 2009;467(1):235-238."},{"issue":"3","key":"bib10","series-title":"J Hand Microsurg","first-page":"139","article-title":"Surgical implications of innervation pattern of the triceps muscle: a cadaveric study","volume":"10","author":"Chaware","year":"2018","unstructured":"Chaware PNSantoshi JAPatel MAhmad MRathinam BAD.Surgical implications of innervation pattern of the triceps muscle: a cadaveric study. J Hand Microsurg. 2018;10(3):139-142."},{"issue":"2","key":"bib11","series-title":"Indian J Orthop","first-page":"353","article-title":"Ulnar nerve innervation to triceps: a cadaveric study and a technical note on partial triceps to biceps transfer","volume":"53","author":"Jain","year":"2019","unstructured":"Jain DKAKumar STShetty N.Ulnar nerve innervation to triceps: a cadaveric study and a technical note on partial triceps to biceps transfer. Indian J Orthop. 2019;53(2):353-356."},{"issue":"8","key":"bib12","series-title":"Clin Anat","first-page":"1028","article-title":"Ulnar nerve innervation of the medial head of the triceps brachii muscle: a cadaveric study","volume":"26","author":"Loukas","year":"2013","unstructured":"Loukas MBellary SSY\u00fczba\u015fio\u011flu NShoja MMTubbs RSSpinner RJ.Ulnar nerve innervation of the medial head of the triceps brachii muscle: a cadaveric study. Clin Anat. 2013;26(8):1028-1030."},{"issue":"5","key":"bib13","series-title":"J Hand Surg Eur Vol","first-page":"430","article-title":"Abnormal innervation of the triceps brachii muscle by the ulnar nerve","volume":"35","author":"Miguel-P\u00e9rez","year":"2010","unstructured":"Miguel-P\u00e9rez MICombalia AArandes JM.Abnormal innervation of the triceps brachii muscle by the ulnar nerve. J Hand Surg Eur Vol. 2010;35(5):430-431."},{"issue":"1","key":"bib14","series-title":"Anat J Afr","first-page":"834","article-title":"Ulnar nerve contribution in the innervation of the triceps brachii muscle ulnar nerve to the triceps brachii","volume":"6","author":"Silva","year":"2017","unstructured":"Silva DLRBarros MPFreire TGSUlnar nerve contribution in the innervation of the triceps brachii muscle ulnar nerve to the triceps brachii. Anat J Afr. 2017;6(1):834-839."},{"issue":"6","key":"bib15","series-title":"Turk Neurosurg","first-page":"949","article-title":"Co-innervation of triceps brachii muscle with variant branch of ulnar nerve","volume":"28","author":"Develi","year":"2018","unstructured":"Develi S.Co-innervation of triceps brachii muscle with variant branch of ulnar nerve. Turk Neurosurg. 2018;28(6):949-953."},{"issue":"suppl 1","key":"bib16","series-title":"FASEB J","first-page":"lb23","article-title":"Variation of the radial nerve, ulnar nerve and axillary nerve in innervation of the three heads of the triceps brachii muscle","volume":"26","author":"Kauffman","year":"2012","unstructured":"Kauffman TOlinger ABorman WFisher C.Variation of the radial nerve, ulnar nerve and axillary nerve in innervation of the three heads of the triceps brachii muscle. FASEB J. 2012;26(suppl 1):lb23."},{"issue":"6","key":"bib17","series-title":"Clin Orthop Relat Res","first-page":"1887","article-title":"Ulnar nerve innervation of the triceps muscle: real or apparent? An anatomic study","volume":"471","author":"Pascual-Font","year":"2013","unstructured":"Pascual-Font AVazquez TMarco FSa\u00f1udo JRRodriguez-Niedenf\u00fchr M.Ulnar nerve innervation of the triceps muscle: real or apparent? An anatomic study. Clin Orthop Relat Res. 2013;471(6):1887-1893."},{"issue":"1","key":"bib18","series-title":"Clin Anat","first-page":"137","article-title":"Relationship between the ulnar nerve and the branches of the radial nerve to the medial head of the triceps brachii muscle","volume":"32","author":"Cho","year":"2019","unstructured":"Cho SHChung IHLee UY.Relationship between the ulnar nerve and the branches of the radial nerve to the medial head of the triceps brachii muscle. Clin Anat. 2019;32(1):137-142."}],"container-title":["Journal of Neurosurgery: Case Lessons"],"original-title":[],"link":[{"URL":"https:\/\/thejns.org\/view\/journals\/j-neurosurg-case-lessons\/10\/9\/article-CASE25484.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/thejns.org\/downloadpdf\/journals\/j-neurosurg-case-lessons\/10\/9\/article-CASE25484.xml","content-type":"text\/html","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/thejns.org\/downloadpdf\/journals\/j-neurosurg-case-lessons\/10\/9\/article-CASE25484.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T11:13:43Z","timestamp":1769685223000},"score":1,"resource":{"primary":{"URL":"https:\/\/thejns.org\/view\/journals\/j-neurosurg-case-lessons\/10\/9\/article-CASE25484.xml"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,9,1]]},"references-count":36,"journal-issue":{"issue":"9"},"URL":"https:\/\/doi.org\/10.3171\/case25484","relation":{},"ISSN":["2694-1902"],"issn-type":[{"value":"2694-1902","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,9,1]]}}}