{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T14:49:19Z","timestamp":1787755759114,"version":"build-2784847793"},"reference-count":22,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"7","content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2025,4,2]]},"abstract":"<jats:sec>\n                    <jats:title>Background:<\/jats:title>\n                    <jats:p>Changing from standing to sitting positions requires rotation of the femur from an almost vertical plane to the horizontal plane. Osteoarthritis of the hip limits hip extension, resulting in less ability to recruit spinopelvic tilt (SPT) while standing and requiring increased SPT while sitting to compensate for the loss of hip range of motion. To date, the effect of total hip arthroplasty (THA) on spinopelvic sitting and standing mechanics has not been reported, particularly in the setting of patients with coexistent sagittal plane spinal deformity.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods:<\/jats:title>\n                    <jats:p>A retrospective review was performed of patients \u226518 years of age undergoing unilateral THA for hip osteoarthritis with sitting and standing radiographs made before and after THA. Alignment was analyzed at baseline and follow-up after THA in both standing and sitting positions in a relaxed posture with the fingers resting on top of the clavicles. Patients were grouped according to the presence or absence of sagittal plane deformity preoperatively into 3 groups: no sagittal plane deformity (normal), thoracolumbar (TL) deformity (pelvic incidence-lumbar lordosis [PI-LL] mismatch &gt; 10\u00b0 and\/or T1-pelvic angle [TPA] &gt; 20\u00b0), or apparent deformity (PI-LL \u2264 10\u00b0 and TPA \u2264 20\u00b0, but sagittal vertical axis [SVA] &gt; 50 mm).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results:<\/jats:title>\n                    <jats:p>In this study, 192 patients were assessed: 64 had TL deformity, 39 had apparent deformity, and 89 had normal alignment. Overall, patients demonstrated a reduction in standing SVA (45 to 34.1 mm; p &lt; 0.001) and an increase in SPT (14.6\u00b0 to 15.7\u00b0; p = 0.03) after THA. There was a greater change in standing SVA (p &lt; 0.001) among patients with apparent deformity (\u221229.0 mm) compared with patients with normal alignment (0.9 mm) and patients with TL deformity (\u221216.3 mm). Those with apparent deformity also experienced the greatest difference (p = 0.03) in postural SPT change (moving from standing to sitting) (\u221210.1\u00b0) from before to after THA when compared with those with normal alignment (\u22123.6\u00b0) and TL deformity (\u22121.2\u00b0). The difference in postural SVA change from before to after THA was also greatest (p &lt; 0.001) in those with apparent deformity (32.1 mm) compared with those with normal alignment (6.5 mm) and TL deformity (17.3 mm).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions:<\/jats:title>\n                    <jats:p>Postural changes in spinopelvic alignment vary after THA depending on the presence of TL deformity or apparent deformity due to hip flexion contracture. Patients with apparent deformity had larger changes in standing and sitting alignment than patients with TL deformity or patients with normal alignment. The assessment of global sagittal alignment findings can be used to predict the likelihood of improvement in sagittal alignment after THA.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Level of Evidence:<\/jats:title>\n                    <jats:p>\n                      Therapeutic\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.24.00108","type":"journal-article","created":{"date-parts":[[2025,2,20]],"date-time":"2025-02-20T14:00:46Z","timestamp":1740060046000},"page":"e23","update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":5,"title":["Classification of Sagittal Spinopelvic Deformity Predicts Alignment Change After Total Hip Arthroplasty"],"prefix":"10.2106","volume":"107","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7218-8861","authenticated-orcid":false,"given":"Aaron J.","family":"Buckland","sequence":"first","affiliation":[{"name":"Melbourne Orthopaedic Group, Melbourne, Australia"},{"name":"Spine and Scoliosis Research Associates Australia, Melbourne, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0968-4950","authenticated-orcid":false,"given":"Fares","family":"Ani","sequence":"additional","affiliation":[{"name":"NYU Langone Health, New York, NY"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7514-4258","authenticated-orcid":false,"given":"Eaman","family":"Balouch","sequence":"additional","affiliation":[{"name":"NYU Langone Health, New York, NY"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5857-6094","authenticated-orcid":false,"given":"Jack","family":"Zhong","sequence":"additional","affiliation":[{"name":"NYU Langone Health, New York, NY"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0308-9648","authenticated-orcid":false,"given":"Jonathan","family":"Vigdorchik","sequence":"additional","affiliation":[{"name":"Hospital for Special Surgery, New York, NY"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0681-7014","authenticated-orcid":false,"given":"Ran","family":"Schwarzkopf","sequence":"additional","affiliation":[{"name":"NYU Langone Health, New York, NY"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4978-2600","authenticated-orcid":false,"given":"Themistocles","family":"Protopsaltis","sequence":"additional","affiliation":[{"name":"NYU Langone Health, New York, NY"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","published-online":{"date-parts":[[2025,2,20]]},"reference":[{"issue":"18","key":"bib1-20250714","doi-asserted-by":"crossref","DOI":"10.2106\/JBJS.17.00403","article-title":"Spine-pelvis-hip relationship in the functioning of a total hip replacement","volume":"100","author":"Ike","year":"2018","journal-title":"J Bone Joint Surg Am."},{"key":"bib2-20250714","doi-asserted-by":"crossref","DOI":"10.1016\/j.math.2015.09.014","article-title":"Investigating the contribution of the upper and lower lumbar spine, relative to hip motion, in everyday tasks","volume":"21","author":"Alqhtani","year":"2016","journal-title":"Man Ther."},{"issue":"2","key":"bib3-20250714","article-title":"Hip-spine relationship: a radio-anatomical study for optimization in acetabular cup positioning","volume":"26","author":"Lazennec","year":"2004","journal-title":"Surg Radiol Anat."},{"issue":"4","key":"bib4-20250714","doi-asserted-by":"crossref","DOI":"10.22603\/ssrr.2017-0074","article-title":"Radiographic assessment of spinopelvic sagittal alignment from sitting to standing position","volume":"2","author":"Suzuki","year":"2018","journal-title":"Spine Surg Relat Res."},{"issue":"Suppl 5","key":"bib5-20250714","article-title":"Hip spine relationships: application to total hip arthroplasty","volume":"17","author":"Lazennec","year":"2007","journal-title":"Hip Int."},{"issue":"6","key":"bib6-20250714","doi-asserted-by":"crossref","DOI":"10.1016\/j.jspd.2019.03.007","article-title":"Spinopelvic compensatory mechanisms for reduced hip motion (ROM) in the setting of hip osteoarthritis","volume":"7","author":"Buckland","year":"2019","journal-title":"Spine Deform."},{"issue":"1","key":"bib7-20250714","doi-asserted-by":"crossref","DOI":"10.1016\/j.arth.2019.08.020","article-title":"Prevalence of sagittal spinal deformity among patients undergoing total hip arthroplasty","volume":"35","author":"Buckland","year":"2020","journal-title":"J Arthroplasty."},{"issue":"6","key":"bib8-20250714","doi-asserted-by":"crossref","DOI":"10.1016\/j.arth.2016.12.039","article-title":"Total hip arthroplasty in the spinal deformity population: does degree of sagittal deformity affect rates of safe zone placement, instability, or revision?","volume":"32","author":"DelSole","year":"2017","journal-title":"J Arthroplasty."},{"issue":"7","key":"bib9-20250714","doi-asserted-by":"crossref","DOI":"10.1302\/0301-620X.101B7.BJJ-2018-1502.R1","article-title":"Evaluation of the spine is critical in the workup of recurrent instability after total hip arthroplasty","volume":"101-B","author":"Vigdorchik","year":"2019","journal-title":"Bone Joint J."},{"issue":"7","key":"bib10-20250714","article-title":"2021 Otto Aufranc Award: A simple hip-spine classification for total hip arthroplasty: validation and a large multicentre series","volume":"103-B","author":"Vigdorchik","year":"2021","journal-title":"Bone Joint J."},{"issue":"2","key":"bib11-20250714","doi-asserted-by":"crossref","DOI":"10.1016\/j.nec.2012.12.007","article-title":"Use of Surgimap Spine in sagittal plane analysis, osteotomy planning, and correction calculation","volume":"24","author":"Akbar","year":"2013","journal-title":"Neurosurg Clin N Am."},{"issue":"23","key":"bib12-20250714","doi-asserted-by":"crossref","DOI":"10.2106\/JBJS.O.00276","article-title":"Acetabular anteversion changes due to spinal deformity correction: bridging the gap between hip and spine surgeons","volume":"97","author":"Buckland","year":"2015","journal-title":"J Bone Joint Surg Am."},{"issue":"23","key":"bib13-20250714","doi-asserted-by":"crossref","DOI":"10.1097\/BRS.0000000000004068","article-title":"Optimal lumbar lordosis correction for adult spinal deformity with severe sagittal imbalance in patients over age 60: role of pelvic tilt and pelvic tilt ratio","volume":"46","author":"Lee","year":"2021","journal-title":"Spine (Phila Pa 1976)."},{"issue":"15","key":"bib14-20250714","doi-asserted-by":"crossref","DOI":"10.1097\/BRS.0000000000000382","article-title":"T1 pelvic angle (TPA) effectively evaluates sagittal deformity and assesses radiographical surgical outcomes longitudinally","volume":"39","author":"Ryan","year":"2014","journal-title":"Spine (Phila Pa 1976)."},{"issue":"9","key":"bib15-20250714","doi-asserted-by":"crossref","DOI":"10.1007\/s00586-018-5509-0","article-title":"Radiological severity of hip osteoarthritis in patients with adult spinal deformity: the effect on spinopelvic and lower extremity compensatory mechanisms","volume":"27","author":"Day","year":"2018","journal-title":"Eur Spine J."},{"issue":"3","key":"bib16-20250714","doi-asserted-by":"crossref","DOI":"10.1177\/112070000901900312","article-title":"Modification of pelvic orientation after total hip replacement in primary osteoarthritis","volume":"19","author":"Sariali","year":"2009","journal-title":"Hip Int."},{"issue":"6","key":"bib17-20250714","doi-asserted-by":"crossref","DOI":"10.1007\/s00586-014-3700-5","article-title":"Characteristics of sagittal spine-pelvis-leg alignment in patients with severe hip osteoarthritis","volume":"24","author":"Weng","year":"2015","journal-title":"Eur Spine J."},{"issue":"9","key":"bib18-20250714","doi-asserted-by":"crossref","DOI":"10.1097\/BRS.0000000000000844","article-title":"Recruitment of compensatory mechanisms in sagittal spinal malalignment is age and regional deformity dependent: a full-standing axis analysis of key radiographical parameters","volume":"40","author":"Diebo","year":"2015","journal-title":"Spine (Phila Pa 1976)."},{"issue":"2","key":"bib19-20250714","doi-asserted-by":"crossref","DOI":"10.1097\/CORR.0000000000000367","article-title":"2018 Frank Stinchfield Award: Spinopelvic hypermobility is associated with an inferior outcome after THA: examining the effect of spinal arthrodesis","volume":"477","author":"Grammatopoulos","year":"2019","journal-title":"Clin Orthop Relat Res."},{"issue":"12","key":"bib20-20250714","doi-asserted-by":"crossref","DOI":"10.1302\/0301-620X.103B12.BJJ-2020-2451.R2","article-title":"Preoperative spinopelvic hypermobility resolves following total hip arthroplasty","volume":"103-B","author":"Sculco","year":"2021","journal-title":"Bone Joint J."},{"issue":"1","key":"bib21-20250714","article-title":"Spinopelvic mobility and acetabular component position for total hip arthroplasty","volume":"99-B","author":"Stefl","year":"2017","journal-title":"Bone Joint J."},{"issue":"1","key":"bib22-20250714","doi-asserted-by":"crossref","DOI":"10.1016\/j.arth.2017.08.013","article-title":"The current knowledge on spinopelvic mobility","volume":"33","author":"Lum","year":"2018","journal-title":"J Arthroplasty."}],"container-title":["Journal of Bone and Joint Surgery"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.ovid.com\/10.2106\/JBJS.24.00108","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T13:51:24Z","timestamp":1787752284000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.ovid.com\/10.2106\/JBJS.24.00108"}},"subtitle":["A Standing and Sitting Radiographic Analysis"],"short-title":[],"issued":{"date-parts":[[2025,2,20]]},"references-count":22,"journal-issue":{"issue":"7","published-print":{"date-parts":[[2025]]}},"URL":"https:\/\/doi.org\/10.2106\/jbjs.24.00108","relation":{},"ISSN":["0021-9355","1535-1386"],"issn-type":[{"value":"0021-9355","type":"print"},{"value":"1535-1386","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,2,20]]}}}