Jean Y Lazennec1, Ian C Clark2, Dominique Folinais3, Imen N Tahar4, Aidin E Pour5. 1. Department of Orthopaedic and Trauma Surgery, Pitié-Salpétrière Hospital Assistance Publique - Hopitaux de Paris, UPMC, Paris, France; Biomechanics Lab, Arts et Metiers Paris-Tech, Paris, France; Department of Anatomy, UPMC, Paris, France. 2. ACE Medical Devices and Engineering, DARF Implant Retrieval Center, Loma Linda University, Loma Linda, California. 3. RIM Maussins-Nollet, Paris, France. 4. Department of Orthopaedic and Trauma Surgery, Pitié-Salpétrière Hospital Assistance Publique - Hopitaux de Paris, UPMC, Paris, France. 5. Department of Orthopaedic Surgery, University of Michigan, Ann Arbor, Michigan.
Abstract
BACKGROUND: This study used EOS imaging of primary total hip arthroplasty (THA) patients, with and without predating spinal fusion, to investigate (1) the impact of spinal fusion on acetabular implant anteversion and inclination, and (2) whether more extensive spinal fusion (fusion starting above the thoracolumbar junction or extension of fusion to the sacrum) affects acetabular implant orientation differently than lumbar only spinal fusion. METHODS: Ninety-three patients had spinal fusion (case group), and 150 patients were without spinal fusion (controls). None of the patients experienced dislocation. The change in sacral slope (SS) and cup orientation from standing to sitting was measured. RESULTS: Mean SS change from the standing to sitting positions was -7.9°in the fusion group vs -18.4°in controls (P = .0001). Mean change in cup inclination from the standing to sitting positions was 4.9°in the fusion group vs 10.2°in controls (P = .0001). Mean change in cup anteversion from standing to sitting positions was 7.1°in the fusion group vs 12.1°in controls (P = .0001). For each additional level of spinal fusion, the change in SS from standing to sitting positions decreased by 1.6(95% confidence interval [CI], 2.2073-1.0741), the change in cup inclination decreased by 0.8(95% CI, 0.380-1.203), and the change in cup anteversion decreased by 0.9(95% CI, 0.518-1.352; P < .001 in all cases). CONCLUSION: Patients with spinal fusion demonstrated less adaptability of the lumbosacral junction. Longer spinal fusion or inclusion of the pelvis in the fusion critically impacts hip-spine biomechanics and significantly affects the ability to compensate in the standing-to-sitting transition.
BACKGROUND: This study used EOS imaging of primary total hip arthroplasty (THA) patients, with and without predating spinal fusion, to investigate (1) the impact of spinal fusion on acetabular implant anteversion and inclination, and (2) whether more extensive spinal fusion (fusion starting above the thoracolumbar junction or extension of fusion to the sacrum) affects acetabular implant orientation differently than lumbar only spinal fusion. METHODS: Ninety-three patients had spinal fusion (case group), and 150 patients were without spinal fusion (controls). None of the patients experienced dislocation. The change in sacral slope (SS) and cup orientation from standing to sitting was measured. RESULTS: Mean SS change from the standing to sitting positions was -7.9°in the fusion group vs -18.4°in controls (P = .0001). Mean change in cup inclination from the standing to sitting positions was 4.9°in the fusion group vs 10.2°in controls (P = .0001). Mean change in cup anteversion from standing to sitting positions was 7.1°in the fusion group vs 12.1°in controls (P = .0001). For each additional level of spinal fusion, the change in SS from standing to sitting positions decreased by 1.6(95% confidence interval [CI], 2.2073-1.0741), the change in cup inclination decreased by 0.8(95% CI, 0.380-1.203), and the change in cup anteversion decreased by 0.9(95% CI, 0.518-1.352; P < .001 in all cases). CONCLUSION:Patients with spinal fusion demonstrated less adaptability of the lumbosacral junction. Longer spinal fusion or inclusion of the pelvis in the fusion critically impacts hip-spine biomechanics and significantly affects the ability to compensate in the standing-to-sitting transition.
Authors: Philip J York; Alan W McGee; Chase S Dean; Justin E Hellwinkel; Christopher J Kleck; Michael R Dayton; Craig A Hogan Journal: Int Orthop Date: 2018-04-28 Impact factor: 3.075
Authors: Daniel Alsoof; Christopher L McDonald; Matthew Kovoor; Bassel G Diebo; Eren O Kuris; Valentin Antoci; Alan H Daniels Journal: Spine Deform Date: 2022-08-03
Authors: Aidin Eslam Pour; Ran Schwarzkopf; Kunj Paresh Kumar Patel; Manan P Anjaria; Jean Yves Lazennec; Lawrence D Dorr Journal: J Orthop Res Date: 2021-03-22 Impact factor: 3.102