{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,31]],"date-time":"2026-03-31T18:10:50Z","timestamp":1774980650620,"version":"3.50.1"},"reference-count":60,"publisher":"BMJ","issue":"3","license":[{"start":{"date-parts":[[2026,3,31]],"date-time":"2026-03-31T00:00:00Z","timestamp":1774915200000},"content-version":"unspecified","delay-in-days":30,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100009397","name":"Medizinischen Fakult\u00e4t, Eberhard Karls Universit\u00e4t T\u00fcbingen","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100009397","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100015739","name":"Bayer Vital","doi-asserted-by":"publisher","award":["Joint Health donations program 2021\/ 2022"],"award-info":[{"award-number":["Joint Health donations program 2021\/ 2022"]}],"id":[{"id":"10.13039\/100015739","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2026,3,5]]},"published-print":{"date-parts":[[2026,3]]},"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>Joint bleeds are the most significant complication in haemophilia, leading to functional impairment and reduced quality of life. Repeated bleeding during early childhood can cause severe physical limitations in adulthood. Early detection of joint damage, combined with therapeutic interventions, has a huge impact on mobility, physical health and long-term quality of life.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods and analysis<\/jats:title>\n                    <jats:p>A novel markerless video motion analysis method using deep neural networks will be explored in this single-centre, prospective, longitudinal pilot feasibility study. The study will include children and young adults with haemophilia, as well as age-matched healthy controls. Standardised video recordings, the Haemophilia Joint Health Score (HJHS), clinical data, accelerometer-based physical activity tracking and questionnaires on quality of life and activity levels will be collected at baseline and after 12\u2009months.<\/jats:p>\n                    <jats:p>For haemophilia patients, individual consultations will be held after each assessment to discuss joint health and possible interventions. Results will be compared with those of healthy participants to assess the method\u2019s feasibility and to explore outcome differences and correlations. The primary focus will be on evaluating the study\u2019s feasibility, practicability, acceptance, possible risks and data quality with regards to a potential future multicentre trial.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Ethics and dissemination<\/jats:title>\n                    <jats:p>\n                      The study was approved by the local Ethics Committee at the Medical Faculty and the University Hospital T\u00fcbingen (project No. 188\/2023BO1, approval 5 July 2023, protocol version 2.1) and registered at the German Clinical Trials Register (registered 22 September 2023,\n                      <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"uri\" xlink:href=\"https:\/\/drks.de\/search\/en\/trial\/DRKS00032707\">https:\/\/drks.de\/search\/en\/trial\/DRKS00032707<\/jats:ext-link>\n                      ). Results will be shared at conferences and in peer-reviewed journals.\n                    <\/jats:p>\n                    <jats:p>This pilot study will explore the feasibility, practicability and acceptance of a protocol using artificial intelligence in gait analysis to identify patients at risk of early joint damage and to monitor the functional status of children and young adults with haemophilia in routine care.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Trial registration number<\/jats:title>\n                    <jats:p>German Clinical Trials Registry (DRKS00032707).<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2025-108291","type":"journal-article","created":{"date-parts":[[2026,3,31]],"date-time":"2026-03-31T17:35:44Z","timestamp":1774978544000},"page":"e108291","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Quantitative and qualitative motion analysis for early detection of joint damage in haemophilia patients: study protocol for a pilot feasibility study at a German haemophilia treatment centre"],"prefix":"10.1136","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4776-1790","authenticated-orcid":false,"given":"Sarah","family":"Schober","sequence":"first","affiliation":[{"name":"Clinic for Paediatrics and Adolescent Medicine, Paediatrics I \u2013 Haematology, Oncology, Gastroenterology, Nephrology, Rheumatology, University Hospital T\u00fcbingen, T\u00fcbingen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7486-3090","authenticated-orcid":false,"given":"Sandra","family":"Hansmann","sequence":"additional","affiliation":[{"name":"Clinic for Paediatrics and Adolescent Medicine, Paediatrics III - Neuropaediatrics, General Paediatrics, Diabetology, Endocrinology, Social Paediatrics, University Hospital T\u00fcbingen, T\u00fcbingen, 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