{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,1]],"date-time":"2026-11-01T11:47:09Z","timestamp":1793533629026,"version":"4.5.0"},"reference-count":20,"publisher":"MJS Publishing, Medical Journals Sweden AB","license":[{"start":{"date-parts":[[2026,6,22]],"date-time":"2026-06-22T00:00:00Z","timestamp":1782086400000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["ActaO"],"abstract":"<jats:p>Background and purpose:\u00a0Hip migration is a common complication in children with cerebral palsy (CP). Although spasticity has long been considered a contributing factor, muscle-specific associations with hip migration remain unclear. We aimed to investigate whether assessed hip spasticity was associated with hip displacement risk in non-ambulant children with CP.Methods:\u00a0In this population-based cohort study using Danish Cerebral Palsy Follow-Up Program (CPOP) data, children classified as Gross Motor Function Classification System (GMFCS) levels IV\u2013V with at least 1 hip radiograph were included. Pathological hip migration was defined as migration percentage (MP) \u2265 30%. Spasticity was assessed using the Modified Ashworth Scale (MAS) for hip adductors, flexors, and extensors. Overall hip spasticity was defined as summed MAS (0, 1\u20133, 4\u20136, 7\u20139). Cumulative incidence was estimated with death as a competing event, and associations were evaluated using Fine\u2013Gray regression adjusted for GMFCS level.Results: 422 children (786 hips) were included; 374 hips (48%) reached MP \u2265 30%, and death occurred as a competing event in 16 patients (25 hips). Higher overall hip spasticity was associated with increased risk of hip migration, with subdistribution hazard ratios (sHRs) of 1.46 (CI 1.05\u20132.01), 1.77 (CI 1.22\u20132.58), and 2.53 (CI 1.59\u20134.02) for MAS 1\u20133, 4\u20136, and 7\u20139, respectively, compared with MAS 0. Adductor spasticity showed the most consistent association with sHRs ranging from 1.44 to 1.97 across MAS categories.Conclusion:\u00a0In children with CP classified as GMFCS levels IV\u2013V, higher clinically assessed hip spasticity\u2014particularly of the hip adductors\u2014was associated with development of a hip at risk for displacement.<\/jats:p>","DOI":"10.2340\/17453674.2026.46169","type":"journal-article","created":{"date-parts":[[2026,6,22]],"date-time":"2026-06-22T13:42:11Z","timestamp":1782135731000},"source":"Crossref","is-referenced-by-count":1,"title":["Association between spasticity of the hip and development of hip displacement in children: a cohort study of 786 hips"],"prefix":"10.2340","volume":"97","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-8527-2695","authenticated-orcid":false,"given":"Muhammed","family":"Bakhtiyar","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Afrim","family":"Iljazi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4841-518X","authenticated-orcid":false,"given":"Anders","family":"Odgaard","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christian","family":"Wong","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2324-6420","authenticated-orcid":false,"given":"Michael M\u00f8rk","family":"Petersen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Balslev-Clausen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1183","published-online":{"date-parts":[[2026,6,22]]},"reference":[{"key":"159741","doi-asserted-by":"crossref","unstructured":"Soo B, Howard J J, Boyd R N, Reid S M, Lanigan A, Wolfe R, et al. Hip displacement in cerebral palsy. J Bone Joint Surg 2006; 88: 121-9. https:\/\/doi.org\/10.2106\/JBJS.E.00071.","DOI":"10.2106\/00004623-200601000-00015"},{"key":"159742","doi-asserted-by":"crossref","unstructured":"Eunson P. Aetiology and epidemiology of cerebral palsy 2012. Available from: https:\/\/doi.org\/10.1016\/j.paed.2012.05.008.","DOI":"10.1016\/j.paed.2012.05.008"},{"key":"159743","doi-asserted-by":"crossref","unstructured":"Graham H K, Rosenbaum P, Paneth N, Dan B, Lin J P, Damiano D L, et al. Cerebral palsy. Nat Rev Dis Primers 2016; 2: 15082. https:\/\/doi.org\/10.1038\/NRDP.2015.82.","DOI":"10.1038\/nrdp.2015.82"},{"key":"159744","doi-asserted-by":"crossref","unstructured":"McIntyre S, Goldsmith S, Webb A, Ehlinger V, Hollung S J, McConnell K, et al. Global prevalence of cerebral palsy: a systematic analysis. 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J Am Acad Orthop Surg 2002; 10: 198-209. https:\/\/doi.org\/10.5435\/00124635-200205000-00006.","DOI":"10.5435\/00124635-200205000-00006"},{"key":"159748","doi-asserted-by":"crossref","unstructured":"Meseguer-Henarejos A B, S\u01cenchez-Meca J, L\u00f3pez-Pina J A, Carles-Hern\u01cendez R. Inter- and intra-rater reliability of the Modified Ashworth Scale: a systematic review and meta-analysis. Eur J Phys Rehabil Med 2018; 54: 576-90. https:\/\/doi.org\/10.23736\/S1973-9087.17.04796-7.","DOI":"10.23736\/S1973-9087.17.04796-7"},{"key":"159749","doi-asserted-by":"crossref","unstructured":"Schmidt S M, H\u00e4gglund G, Alriksson-Schmidt A I. Bone and joint complications and reduced mobility are associated with pain in children with cerebral palsy. 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