System Maintenance Notice

Please note that maintenance work is scheduled between 4 AM and 5 AM - CET. During this time, you may experience reduced performance. Thanks for your patience.

Publications

Journal Article Ahead of print

PubMed: 42929521 DOI: 10.1227/neu.0000000000004264

Is There a Cervical Alignment Threshold Warranting Cervical Inclusion in the Construct?

Neurosurgery

Authors: Peter G Passias, Mohammad Daher, David Liu, Francesca Totis, Drew Millar, Sang Hun Lee, Pratibha Nayak, Themistocles Protopsaltis, David Kojo Hamilton, Han Jo Kim, Thomas Buell, John Moon, Justin Scheer, Anthony Mikula, Darryl Lau, Bassel Diebo, Alan H Daniels, Gregory Mundis, Robert Eastlack, Jeffrey P Mullin, Khaled Kebaish, Praveen Mummaneni, Munish Gupta, Jeffrey Gum, Breton Line, Richard Hostin, Dean Chou, Eric Klineberg, Ricardo B V Fontes, Richard Fessler, Lawrence Lenke, Jay D Turner, Juan S Uribe, Stephen Lewis, Renaud Lafage, Virginie Lafage, Frank Schwab, Shay Bess, Justin Smith, Christopher Shaffrey, Christopher Ames

Affiliations

  • Division of Spine Surgery, Department of Orthopaedic Surgery, Duke University School of Medicine, Durham, North Carolina, USA.
  • Division of Spine Surgery, Department of Neurological Surgery, Duke University School of Medicine, Durham, North Carolina, USA.
  • Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts, USA.
  • Department of Orthopaedic Surgery, Johns Hopkins Medical Center, Baltimore, Maryland, USA.
  • Department of Neurological Surgery, Johns Hopkins Medical Center, Baltimore, Maryland, USA.
  • HCA Research Institute, Center for Outcomes Research Medical City Dallas, Dallas, Texas, USA.
  • Department of Orthopedic Surgery, NYU Langone Orthopedic Hospital, New York, New York, USA.
  • Division of Orthopaedic Surgery, University of Toronto, Toronto, Canada.
  • Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.
  • Department of Orthopedic Surgery, Hospital for Special Surgery, New York, New York, USA.
  • Department of Neurological Surgery, NYU Langone Orthopedic Hospital, New York, New York, USA.
  • Department of Orthopedic Surgery, Mayo Clinic, Rochester, Minnesota, USA.
  • Department of Orthopaedic Surgery, Warren Alpert School of Medicine, Brown University, Providence, Rhode Island, USA.
  • Division of Orthopaedic Surgery, Scripps Clinic, La Jolla, California, USA.
  • Department of Neurological Surgery, University of Buffalo Medical School, Buffalo, New York, USA.
  • Department of Neurological Surgery, University of California, San Francisco, San Francisco, California, USA.
  • Department of Orthopaedic Surgery, Washington University, St. Louis, Missouri, USA.
  • Department of Orthopedic Surgery, Norton Leatherman Spine Center, Louisville, Kentucky, USA.
  • International Spine Study Group, Brighton, Colorado, USA.
  • Department of Orthopaedic Surgery, Southwest Scoliosis Center, Dallas, Texas, USA.
  • Department of Orthopaedic Surgery, Columbia University, New York, New York, USA.
  • The University of Texas Health Science Center at Houston, Houston, Texas, USA.
  • Department of Neurological Surgery, Rush University Medical Center, Chicago, Illinois, USA.
  • Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.
  • Department of Orthopaedics, Lenox Hill Hospital, Northwell Health, New York, New York, USA.
  • Department of Neurosurgery, University of Virginia School of Medicine, Charlottesville, Virginia, USA.

Abstract

BACKGROUND AND OBJECTIVES

Postoperative thoracolumbar (TL) realignment in patients with adult spinal deformity (ASD) may induce cervical spine (CS) decompensation. This study identifies predictors of CS decompensation after TL surgery and defines a baseline CS-alignment threshold based on C2-pelvic angle (C2-PA) for CS inclusion in the TL construct.

METHODS

Patients with ASD undergoing TL fusion to the sacrum with an upper instrumented vertebrae at T2 or below and available baseline radiographs and patient-reported outcome measures (PROMs) were included. CS decompensation was defined as CS surgery or >2 SD above the mean in C2-PA, cervical sagittal vertical axis (cSVA), or T1-slope cervical lordosis (TS-CL) at the studied postoperative time point.

RESULTS

One thousand one hundred ninety patients were included; 166 (13.9%) had CS decompensation after TL surgery, including 24 (2.0%) requiring CS extension. CS decompensation was identified in 81 patients (6.8%) at 6 weeks (4 (0.3%) extensions), 13 (1.2%) at 6 months (2 (0.2%)), 43 (3.9%) at 1 year (7 (0.6%)), and 29 (2.8%) at 2 years (11 (0.9%)). Patients with CS decompensation at 6 months showed worse global and CS alignment at 6 weeks (lumbar lordosis: 53.6 vs 46.3; cSVA: 30.5 vs 38.5; P < .05). CS decompensation at 1 year was associated with worse PROMs (physical component score: 39.0 vs 35.4; Scoliosis research society score: 3.6 vs 3.3; P < .05). CS decompensation at 2 years was associated with worse CS alignment at 1 year (TS-CL: 20.8 vs 28.6; cSVA: 31.1 vs 37.8) and worse PROMs at 2 years. Higher baseline C2-PA was associated with shorter time to CS decompensation. Cox modeling identified baseline C2-PA (hazard ratio [HR] 1.05, 95% CI, 1.03-1.06), TS-CL (HR 1.05, 95% CI, 1.03-1.06), surgical invasiveness (HR 0.99, 95% CI, 0.98-0.99), and upper thoracic instrumentation (HR 2.9, 95% CI, 1.8-4.7) as predictors of CS decompensation, with a C2-PA threshold of 26.2°.

CONCLUSION

Two years after TL ASD surgery, 13.9% had CS decompensation, with 14% requiring CS extension. Baseline CS alignment independently predicted CS decompensation. Patients with preoperative C2-PA >26.2° may benefit from CS inclusion in the TL construct after external validation of this threshold by future research.

MeSH

Neurosurgery, Lordosis, Research, Spine