{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T14:23:35Z","timestamp":1787754215530,"version":"build-2784847793"},"reference-count":28,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"16","content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2026,8,19]]},"abstract":"<jats:sec>\n                    <jats:title>Background:<\/jats:title>\n                    <jats:p>For patients with periacetabular metastases, protrusio acetabuli is a severely painful and mobility-impairing complication that requires subsequent open joint surgery. We aimed to identify specific structural changes that are associated with progression to protrusio acetabuli and to create a scoring system to guide risk stratification.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods:<\/jats:title>\n                    <jats:p>In this single-institution cohort study, we identified all patients who underwent primary surgical stabilization for periacetabular metastases with osteolytic or mixed osteolytic-osteoblastic characteristics from October 2017 through January 2025. Cases of protrusio acetabuli prior to surgical intervention were identified. Pain and ambulatory functional scores and treatment history were recorded. Locations of bone destruction were evaluated using coronal-cut computed tomography (CT) scans obtained within 3 months before clinical presentation (and earlier, as available). Trabecular and subchondral cortical bone mass of the periacetabular weight-bearing portions were indirectly assessed via Hounsfield unit ratio comparisons across scans. Univariable analysis of each feature was performed. The highest-scoring features were used to create a scoring system and analyzed using a receiver operating characteristic (ROC) curve. Finite element analysis was performed for biomechanical validation.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results:<\/jats:title>\n                    <jats:p>Eighty-seven patients (67 non-protrusio [mean age of 65.5 \u00b1 13.0 years; 37 female]; 20 protrusio [mean age of 72.9 \u00b1 10.1 years; 11 female]) were included. Locationally, bone defects, thinning, or linear fractures in the middle-third (apex) alongside contiguous involvement of either the medial- or lateral-third of the weight-bearing dome were highly predictive of protrusio. A &gt;50% cortical bone-mass decrease of the acetabular weight-bearing dome was associated with protrusio (p &lt; 0.05). A radiographic risk scoring system was then constructed using a grading system from low- to high-risk features. ROC analysis showed a score of \u22653.0 as 95.0% sensitive and 91.0% specific for progression to protrusio. Finite element analysis further showed that cortical bone loss of the middle-third (apex) of the weight-bearing dome was critical.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions:<\/jats:title>\n                    <jats:p>We propose the use of clinical and radiographic risk predictors to stratify patients with periacetabular metastases on the basis of the risk of protrusio. Anatomically, surgical stabilization of the middle-third (apex) of the weight-bearing dome is critical to preventing or delaying progression to protrusio.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Level of Evidence:<\/jats:title>\n                    <jats:p>\n                      Prognostic\n                      <jats:underline>Level III<\/jats:underline>\n                      . See Instructions for Authors for a complete description of levels of evidence.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.2106\/jbjs.25.01219","type":"journal-article","created":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T18:05:43Z","timestamp":1776881143000},"page":"1264-1271","update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":0,"title":["Development of a Radiographic Scoring System to Estimate Acetabular Protrusion Risk in Patients with Osteolytic Periacetabular Metastases"],"prefix":"10.2106","volume":"108","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-9045-1844","authenticated-orcid":false,"given":"Will","family":"Jiang","sequence":"first","affiliation":[{"name":"Department of Orthopaedics & Rehabilitation, Yale University, New Haven, Connecticut"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-7235-9832","authenticated-orcid":false,"given":"Donghao","family":"Gan","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics & Rehabilitation, Yale University, New Haven, Connecticut"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5118-5867","authenticated-orcid":false,"given":"Steven","family":"Tommasini","sequence":"additional","affiliation":[{"name":"Division of Biomechanics and Biomedical Engineering, Department of Orthopaedics & Rehabilitation, New Haven, Connecticut"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8572-5216","authenticated-orcid":false,"given":"Igor Y.","family":"Latich","sequence":"additional","affiliation":[{"name":"Department of Biomedical Imaging and Radiology, Yale University, New Haven, Connecticut"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6033-5297","authenticated-orcid":false,"given":"Dieter","family":"Lindskog","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics & Rehabilitation, Yale University, New Haven, Connecticut"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0799-3765","authenticated-orcid":false,"given":"Francis Y.","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics & Rehabilitation, Yale University, New Haven, Connecticut"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","published-online":{"date-parts":[[2026,4,22]]},"reference":[{"issue":"11","key":"bib1-20260819","doi-asserted-by":"crossref","first-page":"2980","DOI":"10.1007\/s11999-010-1391-8","article-title":"The survivorship of protrusio cages for metastatic disease involving the acetabulum","volume":"468","author":"Clayer","year":"2010","journal-title":"Clin Orthop Relat Res."},{"issue":"6","key":"bib2-20260819","doi-asserted-by":"crossref","first-page":"1015","DOI":"10.3390\/cancers17061015","article-title":"Advancements in Surgical Management of Periacetabular Metastases: Emphasizing Minimally Invasive Techniques","volume":"17","author":"Guan","year":"2025","journal-title":"Cancers (Basel)."},{"issue":"4","key":"bib3-20260819","doi-asserted-by":"crossref","first-page":"2731","DOI":"10.3390\/curroncol28040238","article-title":"Emerging Concepts in the Surgical Management of Peri-Acetabular Metastatic Bone Disease","volume":"28","author":"Gazendam","year":"2021","journal-title":"Curr Oncol."},{"issue":"4","key":"bib4-20260819","doi-asserted-by":"crossref","first-page":"653","DOI":"10.2106\/00004623-198163040-00017","article-title":"The management of acetabular insufficiency secondary to metastatic malignant disease","volume":"63","author":"Harrington","year":"1981","journal-title":"J Bone Joint Surg Am."},{"key":"bib5-20260819","doi-asserted-by":"crossref","first-page":"100414","DOI":"10.1016\/j.jbo.2022.100414","article-title":"The Harrington plus reconstruction for pelvic and acetabular metastases","volume":"33","author":"Chimutengwende-Gordon","year":"2022","journal-title":"J Bone Oncol."},{"issue":"1","key":"bib6-20260819","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1148\/128.1.1","article-title":"The adult hip: an anatomic study. Part I: the bony landmarks","volume":"128","author":"Armbuster","year":"1978","journal-title":"Radiology."},{"issue":"2","key":"bib7-20260819","doi-asserted-by":"crossref","first-page":"79","DOI":"10.5435\/00124635-200103000-00002","article-title":"Protrusio acetabuli: diagnosis and treatment","volume":"9","author":"McBride","year":"2001","journal-title":"J Am Acad Orthop Surg."},{"issue":"4","key":"bib8-20260819","doi-asserted-by":"crossref","first-page":"347","DOI":"10.1016\/S0883-5403(89)80036-1","article-title":"Radiographic measurements in protrusio acetabuli","volume":"4","author":"Gates","year":"1989","journal-title":"J Arthroplasty."},{"issue":"9","key":"bib9-20260819","doi-asserted-by":"crossref","first-page":"1260","DOI":"10.3346\/jkms.2015.30.9.1260","article-title":"Analysis of Protrusio Acetabuli Using a CT-based Diagnostic Method in Korean Patients with Marfan Syndrome: Prevalence and Association with Other Manifestations","volume":"30","author":"Chun","year":"2015","journal-title":"J Korean Med Sci."},{"issue":"14","key":"bib10-20260819","doi-asserted-by":"crossref","first-page":"4613","DOI":"10.3390\/jcm12144613","article-title":"Bone Mass Changes Following Percutaneous Radiofrequency Ablation, Osteoplasty, Reinforcement, and Internal Fixation of Periacetabular Osteolytic Metastases","volume":"12","author":"Jiang","year":"2023","journal-title":"J Clin Med."},{"issue":"5","key":"bib11-20260819","doi-asserted-by":"crossref","first-page":"557","DOI":"10.1007\/s00256-011-1255-7","article-title":"The Hounsfield value for cortical bone geometry in the proximal humerus\u2014an in vitro study","volume":"41","author":"Lim Fat","year":"2012","journal-title":"Skeletal Radiol."},{"issue":"6","key":"bib12-20260819","doi-asserted-by":"crossref","first-page":"393","DOI":"10.1016\/0021-9290(75)90075-5","article-title":"The elastic and ultimate properties of compact bone tissue","volume":"8","author":"Reilly","year":"1975","journal-title":"J Biomech."},{"issue":"3","key":"bib13-20260819","doi-asserted-by":"crossref","first-page":"364","DOI":"10.1115\/1.1894148","article-title":"Subject-specific finite element model of the pelvis: development, validation and sensitivity studies","volume":"127","author":"Anderson","year":"2005","journal-title":"J Biomech Eng."},{"issue":"7","key":"bib14-20260819","doi-asserted-by":"crossref","first-page":"897","DOI":"10.1016\/S0021-9290(03)00071-X","article-title":"Trabecular bone modulus-density relationships depend on anatomic site","volume":"36","author":"Morgan","year":"2003","journal-title":"J Biomech."},{"key":"bib15-20260819","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1016\/j.medengphy.2018.11.003","article-title":"Finite element analysis of knee and ankle joint during gait based on motion analysis","volume":"63","author":"Park","year":"2019","journal-title":"Med Eng Phys."},{"key":"bib16-20260819","doi-asserted-by":"crossref","first-page":"106006","DOI":"10.1016\/j.clinbiomech.2023.106006","article-title":"Clinically useful finite element models of the natural ankle - A review","volume":"106","author":"Talbott","year":"2023","journal-title":"Clin Biomech (Bristol)."},{"issue":"9","key":"bib17-20260819","doi-asserted-by":"crossref","first-page":"090802","DOI":"10.1115\/1.4050667","article-title":"In Silico Finite Element Analysis of the Foot Ankle Complex Biomechanics: A Literature Review","volume":"143","author":"Phan","year":"2021","journal-title":"J Biomech Eng."},{"issue":"1","key":"bib18-20260819","doi-asserted-by":"crossref","first-page":"e170","DOI":"10.3928\/01477447-20161017-05","article-title":"Percutaneous Acetabuloplasty for Metastatic Lesions to the Pelvis","volume":"40","author":"Durfee","year":"2017","journal-title":"Orthopedics."},{"key":"bib19-20260819","doi-asserted-by":"crossref","first-page":"27","DOI":"10.21037\/aoj-20-117","article-title":"Skeletal metastatic disease of the acetabulum: historical and evolving techniques for management","volume":"7","author":"Lindsay","year":"2022","journal-title":"Ann Jt."},{"issue":"9","key":"bib20-20260819","doi-asserted-by":"crossref","first-page":"841","DOI":"10.5312\/wjo.v15.i9.841","article-title":"Impacts of radiation therapy on quality of life and pain relief in patients with bone metastases","volume":"15","author":"Hoveidaei","year":"2024","journal-title":"World J Orthop."},{"issue":"7","key":"bib21-20260819","doi-asserted-by":"crossref","first-page":"953","DOI":"10.1001\/jamaoncol.2016.6770","article-title":"Effect of Radiotherapy on Painful Bone Metastases: A Secondary Analysis of the NCIC Clinical Trials Group Symptom Control Trial SC.23","volume":"3","author":"McDonald","year":"2017","journal-title":"JAMA Oncol."},{"issue":"2","key":"bib22-20260819","doi-asserted-by":"crossref","first-page":"95","DOI":"10.3857\/roj.2023.00969","article-title":"The effects of high-dose radiation therapy on bone: a scoping review","volume":"42","author":"Berk","year":"2024","journal-title":"Radiat Oncol J."},{"key":"bib23-20260819","doi-asserted-by":"crossref","first-page":"227","DOI":"10.1186\/s13014-014-0227-1","article-title":"Assessment of the risk factors for impending fractures following radiotherapy for long bone metastases using CT scan-based virtual simulation: a retrospective study","volume":"9","author":"Tatar","year":"2014","journal-title":"Radiat Oncol."},{"issue":"12","key":"bib24-20260819","doi-asserted-by":"crossref","first-page":"7437","DOI":"10.3390\/curroncol31120549","article-title":"High Fracture Risk of Femoral Bone Metastasis Treated with Palliative Radiotherapy in Recent Years","volume":"31","author":"Makita","year":"2024","journal-title":"Curr Oncol."},{"issue":"1","key":"bib25-20260819","doi-asserted-by":"crossref","first-page":"66","DOI":"10.1111\/os.12148","article-title":"Finite element modelling for assessing effect of acetabular component orientation on the basic stress path above acetabular dome","volume":"7","author":"Nie","year":"2015","journal-title":"Orthop Surg."},{"issue":"1","key":"bib26-20260819","first-page":"5150474","article-title":"Clinical Outcome and Fracture Risk Prediction of Benign Bone Tumors on the Acetabular Dome: 7-Year Clinical Experience and a Finite Element Analysis","volume":"2022","author":"Yang","year":"2022","journal-title":"Evid Based Complement Alternat Med."},{"issue":"3","key":"bib27-20260819","doi-asserted-by":"crossref","first-page":"e23.00070","DOI":"10.2106\/JBJS.ST.23.00070","article-title":"Tripod Fixation of Periacetabular Metastatic Lesions Using the IlluminOss Device","volume":"14","author":"Levine","year":"2024","journal-title":"JBJS Essent Surg Tech."},{"issue":"3","key":"bib28-20260819","doi-asserted-by":"crossref","first-page":"666","DOI":"10.1007\/s11999-008-0626-4","article-title":"Radiographic evaluation of the hip has limited reliability","volume":"467","author":"Clohisy","year":"2009","journal-title":"Clin Orthop Relat Res."}],"container-title":["Journal of Bone and Joint Surgery"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.ovid.com\/10.2106\/JBJS.25.01219","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T13:24:10Z","timestamp":1787750650000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.ovid.com\/10.2106\/JBJS.25.01219"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,4,22]]},"references-count":28,"journal-issue":{"issue":"16","published-print":{"date-parts":[[2026]]}},"URL":"https:\/\/doi.org\/10.2106\/jbjs.25.01219","relation":{},"ISSN":["0021-9355","1535-1386"],"issn-type":[{"value":"0021-9355","type":"print"},{"value":"1535-1386","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,4,22]]}}}