{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T08:48:47Z","timestamp":1785833327461,"version":"3.56.0"},"reference-count":13,"publisher":"MJS Publishing, Medical Journals Sweden AB","license":[{"start":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T00:00:00Z","timestamp":1785801600000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JPHS"],"abstract":"<jats:p>Background: The Wassel classification for thumb polydactyly relies on radiographs; however, invisible unossified cartilage in young children can lead to misclassification and suboptimal surgical planning. This study evaluated whether ultrasound improves the accuracy of polydactyly classification compared with radiographs.\nMaterials and methods: This prospective study included 31 cases of radial polydactyly initially classified as Wassel type IV or type II based on radiographs. All patients underwent preoperative ultrasound to identify potential cartilaginous connections between the proximal and distal phalanges. The ultrasound findings were compared against intraoperative exploration, which served as the gold standard for final classification.\nResults: Ultrasound correctly identified cartilaginous connections in the majority of cases, achieving an overall diagnostic accuracy of 93.5%. Thirty eight per cent of radiologic type IV cases were reclassified as type III, and 10% of radiologic type II cases were reclassified as type I after ultrasound detection of hidden connections. The accuracy was 100% for types IV-C and II, whereas type IV-D presented a diagnostic challenge with 75% accuracy. Overall diagnostic accuracy of ultrasound for polydactyly classification was high, with only a small number of misclassifications.\nConclusions: Radiograph-based Wassel classification may misclassify thumb polydactyly in children due to unossified cartilage. Ultrasound allows direct visualization of cartilaginous connections and improves preoperative classification accuracy. Combined use of ultrasound and radiographs provides a more reliable anatomical assessment and may help optimize surgical planning and outcomes.<\/jats:p>","DOI":"10.2340\/jphs.v61.46504","type":"journal-article","created":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T08:40:56Z","timestamp":1785832856000},"page":"203-206","source":"Crossref","is-referenced-by-count":0,"title":["Ultrasound improves preoperative Wassel classification of thumb polydactyly in children"],"prefix":"10.2340","volume":"61","author":[{"given":"Xun","family":"Liang","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bo","family":"He","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1183","published-online":{"date-parts":[[2026,8,4]]},"reference":[{"key":"164684","doi-asserted-by":"crossref","unstructured":"Cheng JC, Chan KM, Ma GF, et al. Polydactyly of the thumb: a surgical plan based on ninety-five cases. J Hand Surg Am. 1984;9(2): 155\u2013164.","DOI":"10.1016\/S0363-5023(84)80133-1"},{"key":"164685","doi-asserted-by":"crossref","unstructured":"Townsend DJ, Lipp EB, Jr, Chun K, et al. Thumb duplication, 66 years\u2019 experience \u2013 a review of surgical complications. J Hand Surg Am. 1994;19(6):973\u2013976.","DOI":"10.1016\/0363-5023(94)90099-X"},{"key":"164686","unstructured":"Wassel HD. The results of surgery for polydactyly of the thumb. A review. Clin Orthop Relat Res. 1969;64:175\u2013193."},{"key":"164687","doi-asserted-by":"crossref","unstructured":"Hung L, Cheng JC, Bundoc R, et al. Thumb duplication at the metacarpophalangeal joint. Management and a new classification. Clin Orthop Relat Res. 1996;Feb;(323):31\u201341.","DOI":"10.1097\/00003086-199602000-00005"},{"key":"164688","doi-asserted-by":"crossref","unstructured":"Yao Y, Zhou H, Li L, et al. Epidemiological statistics of congenital thumb duplication in the Chinese population. J Orthop Surg Res. 2021;16(1):481.","DOI":"10.1186\/s13018-021-02567-3"},{"key":"164689","doi-asserted-by":"crossref","unstructured":"Islam S, Oka I, Fujita S. Anatomical study of preaxial polydactyly in 158 hands. Tohoku J Exp Med. 1992;168(3):459\u2013466.","DOI":"10.1620\/tjem.168.459"},{"key":"164690","doi-asserted-by":"crossref","unstructured":"Al-Qattan MM. The distribution of the types of thumb polydactyly in a Middle Eastern population: a study of 228 hands. J Hand Surg Eur Vol. 2010;35(3):182\u2013187.","DOI":"10.1177\/1753193409352417"},{"key":"164691","doi-asserted-by":"crossref","unstructured":"Dijkman RR, van Nieuwenhoven CA, Selles RW, et al. A multicenter comparative study of two classification systems for radial polydactyly. Plast Reconstr Surg. 2014;134:991\u20131001.","DOI":"10.1097\/PRS.0000000000000590"},{"key":"164692","doi-asserted-by":"crossref","unstructured":"Zhang SJ, Lin HB, Jiang QX, et al. Prenatal diagnosis of triphalangeal thumb-polysyndactyly syndrome by ultrasonography combined with genetic testing: a case report. World J Clin Cases. 2021;9(23):6832\u20136838.","DOI":"10.12998\/wjcc.v9.i23.6832"},{"key":"164693","doi-asserted-by":"crossref","unstructured":"Zhu Y, Fu Y, Lu K, et al. Use of skeletal and soft tissue imaging to guide the surgical repair of misclassified Wassel type VI thumb duplication with convergent deformity. J Plast Reconstr Aesthet Surg. 2025;103:354\u2013362.","DOI":"10.1016\/j.bjps.2025.02.006"},{"key":"164694","doi-asserted-by":"crossref","unstructured":"Zhou L, Lv M, Zeng M, et al. Metacarpal bone plane examination by ultrasonography for the diagnosis of fetal forearm and hand deformity. Sci Rep. 2017;7:42161.","DOI":"10.1038\/srep42161"},{"key":"164695","doi-asserted-by":"crossref","unstructured":"Wang A, Ding J, Wang L, et al. MRI analysis and surgical treatment of Wassel Type IV duplicated thumbs. J Hand Surg Eur Vol. 2021;46(4):360\u2013366.","DOI":"10.1177\/1753193420983213"},{"key":"164696","doi-asserted-by":"crossref","unstructured":"Du M, Jiang L, Wang A, et al. MR imaging provides practical information for preoperative assessment of radial polydactyly with bifurcation at the metacarpophalangeal joint level. Int J Gen Med. 2022;15:2163\u20132169.","DOI":"10.2147\/IJGM.S352501"}],"container-title":["Journal of Plastic Surgery and Hand Surgery"],"original-title":[],"link":[{"URL":"https:\/\/medicaljournalssweden.se\/JPHS\/article\/download\/46504\/55005","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/medicaljournalssweden.se\/JPHS\/article\/download\/46504\/55005","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T08:41:07Z","timestamp":1785832867000},"score":1,"resource":{"primary":{"URL":"https:\/\/medicaljournalssweden.se\/JPHS\/article\/view\/46504"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,4]]},"references-count":13,"URL":"https:\/\/doi.org\/10.2340\/jphs.v61.46504","relation":{},"ISSN":["2000-6764"],"issn-type":[{"value":"2000-6764","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,4]]}}}