Subaraman Ramchandran1, Themistocles S Protopsaltis2, Daniel Sciubba3, Justin K Scheer4, Cyrus M Jalai1, Alan Daniels5, Peter G Passias1, Virginie Lafage6, Han Jo Kim6, Gregory Mundis4, Eric Klineberg7, Robert A Hart8, Justin S Smith9, Christopher Shaffrey9, Christopher P Ames10. 1. Department of Orthopedic Surgery, NYU Langone medical Center, NYU Hospital for Joint Diseases, 301 East 17th Street, New York, NY, USA. 2. Department of Orthopedic Surgery, NYU Langone medical Center, NYU Hospital for Joint Diseases, 301 East 17th Street, New York, NY, USA. themistocles.protopsaltis@nyumc.org. 3. Department of Neurosurgery, Johns Hopkins University Medical Center, Baltimore, MD, USA. 4. Department of Neurosurgery, University of California San Diego, San Diego, CA, USA. 5. Department of Orthopedic Surgery, Brown University Alpert Medical School, Providence, RI, USA. 6. Department of Orthopedic Surgery, Hospital for Special Surgery, New York, NY, USA. 7. Department of Orthopedic Surgery, University of California, Davis, Sacramento, CA, USA. 8. Department of Orthopedic Surgery, Oregon Health and Science Center, Portland, OR, USA. 9. Department of Neurosurgery, University of Virginia Medical Center, Charlottesville, VA, USA. 10. Department of Neurosurgery, University of California San Francisco, San Francisco, CA, USA.
Abstract
PURPOSE: Reciprocal mechanisms for standing alignment have been described in thoraco-lumbar deformity but have not been studied in patients with primary cervical deformity (CD). The purpose of this study is to report upper- and infra-cervical sagittal compensatory mechanisms in patients with CD and evaluate their changes post-operatively. METHODS: Global spinal alignment was studied in a prospective database of operative CD patients. Inclusion criteria were any of the following: cervical kyphosis (CK) > 10°, cervical scoliosis > 10°, cSVA (C2-C7 Sagittal vertical axis) > 4 cm or CBVA (Chin Brow Vertical Angle) > 25°. For this study, patients who had previous fusion outside C2 to T4 segments were excluded. Patients were sub-classified by increasing severity of cervical kyphosis [CL (cervical lordosis): < 0°, CK-low 0°-10°, CK-high > 10°] and cSVA (cSVA-low 0-4 cm, cSVA-mid 4-6 cm, cSVA-high > 6 cm) and were compared for pre- and 3-month post-operative regional and global sagittal alignment to determine compensatory recruitment. RESULTS: 75 CD patients (mean age 61.3 years, 56% women) were included. Patients with progressively larger CK had a progressive increase in C0-C2 (CL = 34°, CK-low = 37°, CK-high = 44°, p = 0.004), C2Slope and T1Slope-CL (p < 0.05). As the cSVA increased, there was progressive increase in C2Slope, T1Slope and TS-CL (p < 0.05) and patients compensated through increasing C0-C2 (cSVA-low = 33°, cSVA-mid = 40°, cSVA-high = 43°, p = 0.007) and pelvic tilt (cSVA-low = 14.9°, cSVA-mid = 24.1°, cSVA-high = 24.9°, p = 0.02). At 3 months post-op, with significant improvement in cervical alignment, there was relaxation of C0-C2 (39°-35°, p = 0.01) which positively correlated with magnitude of deformity correction. CONCLUSIONS: Patients with cervical malalignment compensate with upper cervical hyper-lordosis, presumably for the maintenance of horizontal gaze. As cSVA increases, patients also tend to exhibit increased pelvic retroversion. Following surgical treatment, there was relaxation of upper cervical compensation.
PURPOSE: Reciprocal mechanisms for standing alignment have been described in thoraco-lumbar deformity but have not been studied in patients with primary cervical deformity (CD). The purpose of this study is to report upper- and infra-cervical sagittal compensatory mechanisms in patients with CD and evaluate their changes post-operatively. METHODS: Global spinal alignment was studied in a prospective database of operative CDpatients. Inclusion criteria were any of the following: cervical kyphosis (CK) > 10°, cervical scoliosis > 10°, cSVA (C2-C7 Sagittal vertical axis) > 4 cm or CBVA (Chin Brow Vertical Angle) > 25°. For this study, patients who had previous fusion outside C2 to T4 segments were excluded. Patients were sub-classified by increasing severity of cervical kyphosis [CL (cervical lordosis): < 0°, CK-low 0°-10°, CK-high > 10°] and cSVA (cSVA-low 0-4 cm, cSVA-mid 4-6 cm, cSVA-high > 6 cm) and were compared for pre- and 3-month post-operative regional and global sagittal alignment to determine compensatory recruitment. RESULTS: 75 CDpatients (mean age 61.3 years, 56% women) were included. Patients with progressively larger CK had a progressive increase in C0-C2 (CL = 34°, CK-low = 37°, CK-high = 44°, p = 0.004), C2Slope and T1Slope-CL (p < 0.05). As the cSVA increased, there was progressive increase in C2Slope, T1Slope and TS-CL (p < 0.05) and patients compensated through increasing C0-C2 (cSVA-low = 33°, cSVA-mid = 40°, cSVA-high = 43°, p = 0.007) and pelvic tilt (cSVA-low = 14.9°, cSVA-mid = 24.1°, cSVA-high = 24.9°, p = 0.02). At 3 months post-op, with significant improvement in cervical alignment, there was relaxation of C0-C2 (39°-35°, p = 0.01) which positively correlated with magnitude of deformity correction. CONCLUSIONS:Patients with cervical malalignment compensate with upper cervical hyper-lordosis, presumably for the maintenance of horizontal gaze. As cSVA increases, patients also tend to exhibit increased pelvic retroversion. Following surgical treatment, there was relaxation of upper cervical compensation.
Authors: Virginie Lafage; Christopher Ames; Frank Schwab; Eric Klineberg; Behrooz Akbarnia; Justin Smith; Oheneba Boachie-Adjei; Douglas Burton; Robert Hart; Richard Hostin; Christopher Shaffrey; Kirkham Wood; Shay Bess Journal: Spine (Phila Pa 1976) Date: 2012-02-01 Impact factor: 3.468
Authors: Christopher P Ames; Benjamin Blondel; Justin K Scheer; Frank J Schwab; Jean-Charles Le Huec; Eric M Massicotte; Alpesh A Patel; Vincent C Traynelis; Han Jo Kim; Christopher I Shaffrey; Justin S Smith; Virginie Lafage Journal: Spine (Phila Pa 1976) Date: 2013-10-15 Impact factor: 3.468
Authors: Taemin Oh; Justin K Scheer; Robert Eastlack; Justin S Smith; Virginie Lafage; Themistocles S Protopsaltis; Eric Klineberg; Peter G Passias; Vedat Deviren; Richard Hostin; Munish Gupta; Shay Bess; Frank Schwab; Christopher I Shaffrey; Christopher P Ames Journal: J Neurosurg Spine Date: 2015-03-20
Authors: Justin K Scheer; Jessica A Tang; Justin S Smith; Frank L Acosta; Themistocles S Protopsaltis; Benjamin Blondel; Shay Bess; Christopher I Shaffrey; Vedat Deviren; Virginie Lafage; Frank Schwab; Christopher P Ames Journal: J Neurosurg Spine Date: 2013-06-14
Authors: H Koller; C Ames; H Mehdian; R Bartels; R Ferch; V Deriven; H Toyone; C Shaffrey; J Smith; W Hitzl; J Schröder; Yohan Robinson Journal: Eur Spine J Date: 2018-11-27 Impact factor: 3.134
Authors: Peter G Passias; Haddy Alas; Renaud Lafage; Bassel G Diebo; Irene Chern; Christopher P Ames; Paul Park; Khoi D Than; Alan H Daniels; D Kojo Hamilton; Douglas C Burton; Robert A Hart; Shay Bess; Breton G Line; Eric O Klineberg; Christopher I Shaffrey; Justin S Smith; Frank J Schwab; Virginie Lafage Journal: J Craniovertebr Junction Spine Date: 2019 Jul-Sep