title: Is It Possible To Evaluate the Ideal Cervical Alignment for Each Patient Needing Surgery? An Easy Rule To Determine the Appropriate Cervical Lordosis in Preoperative Planning.
abstract: BACKGROUND
  Cervical sagittal alignment parameters are essential to plan stages of surgery. The aims of this study were to evaluate the relationship between cervical sagittal alignment parameters and surgical outcomes after anterior cervical arthrodesis; to identify parameters linked to a better outcome; to determine the role of the T1 slope, C7 slope, cervical lordosis, and C2-C7 plumb line; and to describe an innovative method to calculate cervical lordosis. A cohort of 70 patients without cervical kyphosis was included in our retrospective study. We analyzed C7 slope, T1 slope, cervical lordosis, and the C2-C7 sagittal vertical axis (SVA). Clinical postoperative outcomes were evaluated with the Neck Disability Index (NDI) and Visual Analog Scale (VAS) score.
  
  
  RESULTS
  Significant correlation was found between the C2-C7 SVA, C7 slope, T1 slope and the CL/C7 slope. Statistically significant differences were found between group 1 (NDI = 0; VAS = 0) and group 3 (NDI > 17; VAS > 5) regarding C2-C7 SVA (P = 0.0026), C7 slope (P = 0.0014), T1 slope (P = 0.0095) and CL/C7slope (P = 0.0012). A value less than 25 mm found in the C2-C7 SVA correlate with positive outcomes. C7 slope correlated with NDI and VAS (P = 0.0014). CL/C7 slope ratio is significantly correlated to NDI and VAS scores (ratio: -0.52; P = 0.0012). Patients with CL/C7 slope greater than 0.7 had better clinical outcomes.
  
  
  CONCLUSIONS
  Sagittal parameters are directly correlated with clinical outcome. If C7 slope increases, higher cervical lordosis is necessary to obtain a good outcome. CL/C7 slope (0.7) multiplied by C7 slope can determine the ideal lordosis.
authors.affiliation: Department of Neuroscience (Neurosurgery Section), University of Turin, Turin, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Ajello
authors.affiliation: Department of Neuroscience (Neurosurgery Section), University of Turin, Turin, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Marengo
authors.affiliation: Department of Neuroscience (Neurosurgery Section), University of Turin, Turin, Italy. Electronic address: giulia.pilloni@libero.it.
authors.forename: Giulia
authors.initials: G
authors.lastname: Pilloni
authors.affiliation: Department of Neuroscience (Neurosurgery Section), University of Turin, Turin, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Penner
authors.affiliation: Department of Neuroscience (Neurosurgery Section), University of Turin, Turin, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Vercelli
authors.affiliation: Department of Neuroscience (Neurosurgery Section), University of Turin, Turin, Italy.
authors.forename: Federico
authors.initials: F
authors.lastname: Pecoraro
authors.affiliation: Department of Neuroscience (Neurosurgery Section), University of Turin, Turin, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Zenga
authors.affiliation: Department of Orthopaedic Surgery, The Rothman Institute at Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
authors.forename: Alexander R
authors.initials: AR
authors.lastname: Vaccaro
authors.affiliation: Department of Neuroscience (Neurosurgery Section), University of Turin, Turin, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Ducati
authors.affiliation: Department of Neuroscience (Neurosurgery Section), University of Turin, Turin, Italy.
authors.forename: Diego
authors.initials: D
authors.lastname: Garbossa
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D059925:Anatomic Landmarks / Q000000981:diagnostic imaging*; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging* / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011300:Preoperative Care / Q000379:methods*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013123:Spinal Fusion / Q000379:methods*; D025321:Surgery, Computer-Assisted / Q000379:methods*; D016896:Treatment Outcome
keywords: Cervical degenerative disease; Cervical lordosis; Cervical sagittal alignment