{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T14:37:47Z","timestamp":1787755067829,"version":"build-2784847793"},"reference-count":49,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"11","content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2022,6,1]]},"abstract":"<jats:sec>\n                    <jats:title>Background:<\/jats:title>\n                    <jats:p>Hip dysplasia is characterized by insufficient acetabular coverage around the femoral head, which leads to instability, pain, and injury. Periacetabular osteotomy (PAO) aims to restore acetabular coverage and function, but its effects on capsular mechanics and joint stability are still unclear. The purpose of this study was to examine the effects of PAO on capsular mechanics and joint range of motion in dysplastic hips.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods:<\/jats:title>\n                    <jats:p>Twelve cadaveric dysplastic hips (denuded to bone and capsule) were mounted onto a robotic tester and tested in multiple positions: (1) full extension, (2) neutral 0\u00b0, (3) flexion of 30\u00b0, (4) flexion of 60\u00b0, and (5) flexion of 90\u00b0. In each position, the hips underwent internal and external rotation, abduction, and adduction using 5 Nm of torque. Each hip then underwent PAO to reorient the acetabular fragment, preserving the capsular ligaments, and was retested.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results:<\/jats:title>\n                    <jats:p>\n                      The PAO reduced internal rotation in flexion of 90\u00b0 (\u2206\n                      <jats:sub>IR<\/jats:sub>\n                      = \u20135\u00b0; p = 0.003), and increased external rotation in flexion of 60\u00b0 (\u2206\n                      <jats:sub>ER<\/jats:sub>\n                      = +7\u00b0; p = 0.001) and flexion of 90\u00b0 (\u2206\n                      <jats:sub>ER<\/jats:sub>\n                      = +11\u00b0; p = 0.001). The PAO also reduced abduction in extension (\u2206\n                      <jats:sub>ABD<\/jats:sub>\n                      = \u201310\u00b0; p = 0.002), neutral 0\u00b0 (\u2206\n                      <jats:sub>ABD<\/jats:sub>\n                      = \u20137\u00b0; p = 0.001), and flexion of 30\u00b0 (\u2206\n                      <jats:sub>ABD<\/jats:sub>\n                      = \u20138\u00b0; p = 0.001), but increased adduction in neutral 0\u00b0 (\u2206\n                      <jats:sub>ADD<\/jats:sub>\n                      = +9\u00b0; p = 0.001), flexion of 30\u00b0 (\u2206\n                      <jats:sub>ADD<\/jats:sub>\n                      = +11\u00b0; p = 0.002), and flexion of 60\u00b0 (\u2206\n                      <jats:sub>ADD<\/jats:sub>\n                      = +11\u00b0; p = 0.003).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions:<\/jats:title>\n                    <jats:p>PAO caused reductions in hip abduction and internal rotation but greater increases in hip adduction and external rotation. The osseous acetabular structure and capsule both play a role in the balance between joint mobility and stability after PAO.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.2106\/jbjs.21.00405","type":"journal-article","created":{"date-parts":[[2022,2,8]],"date-time":"2022-02-08T15:00:08Z","timestamp":1644332408000},"page":"1015-1023","update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":5,"title":["Capsular Mechanics After Periacetabular Osteotomy for Hip Dysplasia"],"prefix":"10.2106","volume":"104","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9413-9294","authenticated-orcid":false,"given":"K.C. Geoffrey","family":"Ng","sequence":"first","affiliation":[{"name":"Robarts Research Institute, Western University, London, Ontario, Canada"},{"name":"Department of Medical Biophysics, Western University, London, Ontario, Canada"},{"name":"Department of Medical Imaging, Western University, London, Ontario, Canada"},{"name":"Department of Surgery, Western University, London, Ontario, Canada"},{"name":"MSk Lab, Department of Surgery and Cancer, Imperial College London, London, United Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6713-2137","authenticated-orcid":false,"given":"Marcus J.K.","family":"Bankes","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics, Guy\u2019s and St Thomas\u2019 NHS Foundation Trust, London, United Kingdom"},{"name":"Fortius Clinic, London, United Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0570-159X","authenticated-orcid":false,"given":"Hadi","family":"El Daou","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Imperial College London, London, United Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7667-9994","authenticated-orcid":false,"given":"Paul E.","family":"Beaul\u00e9","sequence":"additional","affiliation":[{"name":"Division of Orthopaedic Surgery, University of Ottawa, Ottawa, Ontario, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6095-8822","authenticated-orcid":false,"given":"Justin P.","family":"Cobb","sequence":"additional","affiliation":[{"name":"MSk Lab, Department of Surgery and Cancer, Imperial College London, London, United Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8496-6889","authenticated-orcid":false,"given":"Jonathan R.T.","family":"Jeffers","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Imperial College London, London, United Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","published-online":{"date-parts":[[2022,2,8]]},"reference":[{"key":"bib1-20250430","first-page":"154","article-title":"The natural history of congenital dislocation of the hip: a critical review","volume":"137","author":"Wedge","year":"1978","journal-title":"Clin Orthop Relat Res."},{"key":"bib2-20250430","doi-asserted-by":"crossref","first-page":"20","DOI":"10.1097\/00003086-198612000-00004","article-title":"Etiology of osteoarthritis of the hip","volume":"213","author":"Harris","year":"1986","journal-title":"Clin Orthop Relat Res."},{"issue":"2","key":"bib3-20250430","doi-asserted-by":"crossref","first-page":"264","DOI":"10.1007\/s11999-007-0060-z","article-title":"The etiology of osteoarthritis of the hip: an integrated mechanical concept","volume":"466","author":"Ganz","year":"2008","journal-title":"Clin Orthop Relat Res."},{"issue":"7","key":"bib4-20250430","doi-asserted-by":"crossref","first-page":"2233","DOI":"10.1007\/s11999-012-2651-6","article-title":"Lateral center-edge angle on conventional radiography and computed tomography","volume":"471","author":"Monazzam","year":"2013","journal-title":"Clin Orthop Relat Res."},{"issue":"9S","key":"bib5-20250430","doi-asserted-by":"crossref","first-page":"S20","DOI":"10.1016\/j.arth.2017.02.067","article-title":"A Contemporary Definition of Hip Dysplasia and Structural Instability: Toward a Comprehensive Classification for Acetabular Dysplasia","volume":"32","author":"Wilkin","year":"2017","journal-title":"J Arthroplasty."},{"issue":"4","key":"bib6-20250430","doi-asserted-by":"crossref","first-page":"1234","DOI":"10.1007\/s11999-014-4038-3","article-title":"What are the radiographic reference values for acetabular under- and overcoverage?","volume":"473","author":"Tannast","year":"2015","journal-title":"Clin Orthop Relat Res."},{"issue":"3","key":"bib7-20250430","doi-asserted-by":"crossref","first-page":"861","DOI":"10.1007\/s11999-016-5137-0","article-title":"The Femoro-Epiphyseal Acetabular Roof (FEAR) Index: A New Measurement Associated With Instability in Borderline Hip Dysplasia?","volume":"475","author":"Wyatt","year":"2017","journal-title":"Clin Orthop Relat Res."},{"key":"bib8-20250430","doi-asserted-by":"crossref","first-page":"26","DOI":"10.1097\/00003086-198807000-00006","article-title":"A new periacetabular osteotomy for the treatment of hip dysplasias. 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