{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,3]],"date-time":"2026-05-03T10:32:35Z","timestamp":1777804355781,"version":"3.51.4"},"reference-count":21,"publisher":"SAGE Publications","issue":"4","license":[{"start":{"date-parts":[[1991,10,1]],"date-time":"1991-10-01T00:00:00Z","timestamp":686275200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J Child Neurol"],"published-print":{"date-parts":[[1991,10]]},"abstract":"<jats:p>The diagnostic muscle biopsy finding in severe infantile spinal muscular atrophy (Werdnig-Hoffmann disease, SMA type 1) is considered to be large-group atrophy with isolated clusters of hypertrophic type I myofibers. We present a unique case of severe infantile spinal muscular atrophy with selective hypertrophy of type II myofibers. A male infant presented at age 2 months with breathing difficulties and by age 4 months was hypotonic and weak. Electromyography revealed denervation in all extremity muscles, and nerve conduction velocities were normal but with small compound muscle action potentials. Quadriceps muscle biopsy revealed many hypertrophied type II myofibers (myofibers with a mean least diameter of 25.4 \u03bcm). In contrast, the largest type I myofibers were 20 \u03bcm in least diameter (mean diameter, 14.9 \u03bcm), and there was a normal-size population of type II fibers (mean diameter, 15.7 \u03bcm). In addition, sheets of atrophic type I and type II fibers averaged 2.0 \u03bcm in least diameter. Sural nerve biopsy was normal. Breathing difficulties progressed, with death ensuing at age 5\u00bd months. Autopsy revealed atrophy of ventral spinal roots with normal dorsal roots. There was loss of anterior horn cells, while remnant neurons were reduced in size. No other pathologic changes were identified. This case indicates that in severe infantile spinal muscular atrophy, relative sparing of the motor units with type II myofibers may occur. (J Child Neurol 1991;6:329-334).<\/jats:p>","DOI":"10.1177\/088307389100600408","type":"journal-article","created":{"date-parts":[[2008,12,24]],"date-time":"2008-12-24T02:13:25Z","timestamp":1230084805000},"page":"329-334","source":"Crossref","is-referenced-by-count":16,"title":["Selective Type II Muscle Fiber Hypertrophy in Severe Infantile Spinal Muscular Atrophy"],"prefix":"10.1177","volume":"6","author":[{"given":"Douglas W.","family":"Kingma","sequence":"first","affiliation":[{"name":"Departments of Pathology, University of Oklahoma Health Sciences Center and Veterans Affairs Medical Center, Oklahoma City, OK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daniel L.","family":"Feeback","sequence":"additional","affiliation":[{"name":"Department of Anatomical Sciences, University of Oklahoma Health Sciences Center and Veterans Affairs Medical Center, Oklahoma City, OK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Warren A.","family":"Marks","sequence":"additional","affiliation":[{"name":"Department of Neurology, University of Oklahoma Health Sciences Center and Veterans Affairs Medical Center, Oklahoma City, OK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gary B.","family":"Bobele","sequence":"additional","affiliation":[{"name":"Department of Neurology, University of Oklahoma Health Sciences Center and Veterans Affairs Medical Center, Oklahoma City, OK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Richard W.","family":"Leech","sequence":"additional","affiliation":[{"name":"Departments of Pathology, University of Oklahoma Health Sciences Center and Veterans Affairs Medical Center, Oklahoma City, OK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Roger A.","family":"Brumback","sequence":"additional","affiliation":[{"name":"Departments of Pathology, University of Oklahoma Health Sciences Center and Veterans Affairs Medical Center, Oklahoma City, OK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"179","published-online":{"date-parts":[[1991,10,1]]},"reference":[{"key":"atypb1","doi-asserted-by":"publisher","DOI":"10.1001\/archneur.1961.00450140022003"},{"key":"atypb2","volume-title":"Muscle Biopsy: A Practical Approach","author":"Dubowitz V.","year":"1985","edition":"2"},{"key":"atypb3","volume-title":"Muscle Disorders in Childhood","author":"Dubowitz V.","year":"1978"},{"key":"atypb4","author":"Dubowitz V.","year":"1989","journal-title":"Year Book Medical"},{"key":"atypb5","unstructured":"Hausmanowa-Petrusewicz I., Fidzianska-Dolot A.: Clinical features of infantile and juvenile spinal muscular atrophy, in Gamstorp I, Sarnat HB (eds): Progressive Spinal Muscular Atrophies. New York , Raven Press, 1984, pp 31-42."},{"key":"atypb6","doi-asserted-by":"publisher","DOI":"10.1093\/brain\/93.1.15"},{"key":"atypb7","doi-asserted-by":"publisher","DOI":"10.1212\/WNL.13.12.1059"},{"key":"atypb8","unstructured":"Fidzianska-Dolot A., Hausmanowa-Petrusewicz I.: Morphology of the lower motor neuron and muscle, in Gamstorp I, Sarnat HB (eds): Progressive Spinal Muscular Atrophies. New York, Raven Press, 1984, pp 55-89."},{"key":"atypb9","unstructured":"Sarnat HB: Commentary: Pathology of spinal muscular atrophy, in Gamstorp I, Sarnat HB (eds): Progressive Spinal Muscular Atrophies. New York, Raven Press, 1984, pp 91-110."},{"key":"atypb10","doi-asserted-by":"publisher","DOI":"10.1177\/088307388600100103"},{"key":"atypb11","volume-title":"Color Atlas of Muscle Histochemistry","author":"Brumback RA","year":"1984"},{"key":"atypb12","doi-asserted-by":"publisher","DOI":"10.1212\/WNL.19.6.591"},{"key":"atypb13","doi-asserted-by":"publisher","DOI":"10.1007\/BF00687950"},{"key":"atypb14","first-page":"179","volume":"8","author":"Gibbels E.","year":"1989","journal-title":"Clin Neuropathol"},{"key":"atypb15","doi-asserted-by":"publisher","DOI":"10.1016\/0014-4886(89)90190-8"},{"key":"atypb16","doi-asserted-by":"publisher","DOI":"10.1177\/088307388800300409"},{"key":"atypb17","doi-asserted-by":"publisher","DOI":"10.1002\/mus.880080812"},{"key":"atypb18","doi-asserted-by":"publisher","DOI":"10.1002\/mus.880100110"},{"key":"atypb19","doi-asserted-by":"publisher","DOI":"10.1007\/BF00685012"},{"key":"atypb20","doi-asserted-by":"publisher","DOI":"10.1007\/BF00689549"},{"key":"atypb21","doi-asserted-by":"publisher","DOI":"10.1007\/BF00689556"}],"container-title":["Journal of Child Neurology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/088307389100600408","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/088307389100600408","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T20:39:47Z","timestamp":1777495187000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/10.1177\/088307389100600408"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1991,10]]},"references-count":21,"journal-issue":{"issue":"4","published-print":{"date-parts":[[1991,10]]}},"alternative-id":["10.1177\/088307389100600408"],"URL":"https:\/\/doi.org\/10.1177\/088307389100600408","relation":{},"ISSN":["0883-0738","1708-8283"],"issn-type":[{"value":"0883-0738","type":"print"},{"value":"1708-8283","type":"electronic"}],"subject":[],"published":{"date-parts":[[1991,10]]}}}