Maximilian T Löffler1,2, Nico Sollmann1,3,4, Egon Burian1, Amirhossein Bayat1, Kaywan Aftahy5, Thomas Baum1, Bernhard Meyer5, Yu-Mi Ryang5,6, Jan S Kirschke1,3. 1. Department of Diagnostic and Interventional Neuroradiology, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany. 2. Department of Diagnostic and Interventional Radiology, University Medical Center Freiburg, Freiburg im Breisgau, Germany. 3. TUM-Neuroimaging Center, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany. 4. Department of Diagnostic and Interventional Radiology, University Hospital Ulm, Ulm, Germany. 5. Department of Neurosurgery, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany. 6. Department of Neurosurgery, Helios Klinikum Berlin-Buch, Berlin, Germany.
Abstract
Objective: Decreased bone mineral density (BMD) impairs screw purchase in trabecular bone and can cause screw loosening following spinal instrumentation. Existing computed tomography (CT) scans could be used for opportunistic osteoporosis screening for decreased BMD. Purpose of this case-control study was to investigate the association of opportunistically assessed BMD with the outcome after spinal surgery with semi-rigid instrumentation for lumbar degenerative instability. Methods: We reviewed consecutive patients that had primary surgery with semi-rigid instrumentation in our hospital. Patients that showed screw loosening in follow-up imaging qualified as cases. Patients that did not show screw loosening or-if no follow-up imaging was available (n = 8)-reported benefit from surgery ≥ 6 months after primary surgery qualified as controls. Matching criteria were sex, age, and surgical construct. Opportunistic BMD screening was performed at L1 to L4 in perioperative CT scans by automatic spine segmentation and using asynchronous calibration. Processing steps of this deep learning-driven approach can be reproduced using the freely available online-tool Anduin (https://anduin.bonescreen.de). Area under the curve (AUC) was calculated for BMD as a predictor of screw loosening. Results: Forty-six elderly patients (69.9 ± 9.1 years)-23 cases and 23 controls-were included. The majority of surgeries involved three spinal motion segments (n = 34). Twenty patients had low bone mass and 13 had osteoporotic BMD. Cases had significantly lower mean BMD (86.5 ± 29.5 mg/cm³) compared to controls (118.2 ± 32.9 mg/cm³, p = 0.001), i.e. patients with screw loosening showed reduced BMD. Screw loosening was best predicted by a BMD < 81.8 mg/cm³ (sensitivity = 91.3%, specificity = 56.5%, AUC = 0.769, p = 0.002). Conclusion: Prevalence of osteoporosis or low bone mass (BMD ≤ 120 mg/cm³) was relatively high in this group of elderly patients undergoing spinal surgery. Screw loosening was associated with BMD close to the threshold for osteoporosis (< 80 mg/cm³). Opportunistic BMD screening is feasible using the presented approach and can guide the surgeon to take measures to prevent screw loosening and to increase favorable outcomes.
Objective: Decreased bone mineral density (BMD) impairs screw purchase in trabecular bone and can cause screw loosening following spinal instrumentation. Existing computed tomography (CT) scans could be used for opportunistic osteoporosis screening for decreased BMD. Purpose of this case-control study was to investigate the association of opportunistically assessed BMD with the outcome after spinal surgery with semi-rigid instrumentation for lumbar degenerative instability. Methods: We reviewed consecutive patients that had primary surgery with semi-rigid instrumentation in our hospital. Patients that showed screw loosening in follow-up imaging qualified as cases. Patients that did not show screw loosening or-if no follow-up imaging was available (n = 8)-reported benefit from surgery ≥ 6 months after primary surgery qualified as controls. Matching criteria were sex, age, and surgical construct. Opportunistic BMD screening was performed at L1 to L4 in perioperative CT scans by automatic spine segmentation and using asynchronous calibration. Processing steps of this deep learning-driven approach can be reproduced using the freely available online-tool Anduin (https://anduin.bonescreen.de). Area under the curve (AUC) was calculated for BMD as a predictor of screw loosening. Results: Forty-six elderly patients (69.9 ± 9.1 years)-23 cases and 23 controls-were included. The majority of surgeries involved three spinal motion segments (n = 34). Twenty patients had low bone mass and 13 had osteoporotic BMD. Cases had significantly lower mean BMD (86.5 ± 29.5 mg/cm³) compared to controls (118.2 ± 32.9 mg/cm³, p = 0.001), i.e. patients with screw loosening showed reduced BMD. Screw loosening was best predicted by a BMD < 81.8 mg/cm³ (sensitivity = 91.3%, specificity = 56.5%, AUC = 0.769, p = 0.002). Conclusion: Prevalence of osteoporosis or low bone mass (BMD ≤ 120 mg/cm³) was relatively high in this group of elderly patients undergoing spinal surgery. Screw loosening was associated with BMD close to the threshold for osteoporosis (< 80 mg/cm³). Opportunistic BMD screening is feasible using the presented approach and can guide the surgeon to take measures to prevent screw loosening and to increase favorable outcomes.
Authors: Stefan M Knöller; Georg Meyer; Christina Eckhardt; Christoph A Lill; Erich Schneider; Berend Linke Journal: Spine (Phila Pa 1976) Date: 2005-05-01 Impact factor: 3.468
Authors: Klaus Engelke; André Mastmeyer; Valérie Bousson; Thomas Fuerst; Jean-Denis Laredo; Willi A Kalender Journal: Bone Date: 2008-11-25 Impact factor: 4.398
Authors: Roland Duculan; Alex M Fong; John A Carrino; Frank P Cammisa; Andrew A Sama; Alexander P Hughes; Darren R Lebl; James C Farmer; Russel C Huang; Harvinder S Sandhu; Carol A Mancuso; Federico P Girardi Journal: HSS J Date: 2022-06-07
Authors: Michael Dieckmeyer; Maximilian Thomas Löffler; Malek El Husseini; Anjany Sekuboyina; Bjoern Menze; Nico Sollmann; Maria Wostrack; Claus Zimmer; Thomas Baum; Jan Stefan Kirschke Journal: Front Endocrinol (Lausanne) Date: 2022-05-20 Impact factor: 6.055
Authors: Tobias Greve; Nithin Manohar Rayudu; Michael Dieckmeyer; Christof Boehm; Stefan Ruschke; Egon Burian; Christopher Kloth; Jan S Kirschke; Dimitrios C Karampinos; Thomas Baum; Karupppasamy Subburaj; Nico Sollmann Journal: Front Endocrinol (Lausanne) Date: 2022-07-11 Impact factor: 6.055
Authors: Sebastian Rühling; Andreas Scharr; Nico Sollmann; Maria Wostrack; Maximilian T Löffler; Bjoern Menze; Anjany Sekuboyina; Malek El Husseini; Rickmer Braren; Claus Zimmer; Jan S Kirschke Journal: Eur Radiol Date: 2022-04-06 Impact factor: 7.034
Authors: Nico Sollmann; Nithin Manohar Rayudu; Long Yu Yeung; Anjany Sekuboyina; Egon Burian; Michael Dieckmeyer; Maximilian T Löffler; Benedikt J Schwaiger; Alexandra S Gersing; Jan S Kirschke; Thomas Baum; Karupppasamy Subburaj Journal: Diagnostics (Basel) Date: 2021-03-06
Authors: Nico Sollmann; Edoardo A Becherucci; Christof Boehm; Malek El Husseini; Stefan Ruschke; Egon Burian; Jan S Kirschke; Thomas M Link; Karupppasamy Subburaj; Dimitrios C Karampinos; Roland Krug; Thomas Baum; Michael Dieckmeyer Journal: Front Endocrinol (Lausanne) Date: 2022-01-04 Impact factor: 5.555