title: Guideline for C1 Lateral Mass and C2 Pedicle Screw Choices in Children Younger Than 6 Years.
abstract: METHODS
  Prospective study.
  
  
  OBJECTIVE
  To analyze the most feasible choice of C1 lateral mass (C1LM) and C2 pedicle (C2P) screw in upper cervical surgeries for children younger than 6 years.
  
  
  BACKGROUND
  The C1LM and C2P screw technique is a stable cervical vertebrae internal fixation method in upper cervical surgery. Some tomographic studies have indicated the feasibility of insertion of C1LM and C2P screws in children. Their results, however, varied widely, and no consensus was achieved regarding C1LM and C2P screw choices for different ages in the pediatric population, sex, and laterality.
  
  
  METHODS
  The computed tomography images of 250 patients (age 2-6 yr) were studied. The inner diameter and length for each C1LM and C2P were measured in axial view. Height was measured in sagittal view. Screw choice was considered feasible when a sample maintained an additional 0.5 mm bone cortex at the inner diameter, length, and height at the same time. Analyses with the Student t test were performed for age, sex, and laterality. The screw choice was evaluated with a feasibility percentage.
  
  
  RESULTS
  Statistical differences were found between different ages, sex, and laterality for C1LM length (P < 0.001) and C2P length (P < 0.001). Screws of different sizes were recommended for each age group, sex, and laterality, with a feasibility percentage.
  
  
  CONCLUSIONS
  The use of a 3.5-mm lateral mass and pedicle screw in 2- to 6-year-old children was feasible in the majority of cases. Age, sex, and laterality should all be considered when choosing screw sizes in pediatric upper cervical surgeries. This information can be particularly helpful for preoperative planning for C1-C2 internal fixation.
  
  
  METHODS
  3.
authors.affiliation: Orthopedics Department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Daoyang
authors.initials: D
authors.lastname: Fan
authors.affiliation: Orthopedics Department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Ruipeng
authors.initials: R
authors.lastname: Song
authors.affiliation: Orthopedics Department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Gynecology Department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Ruimin
authors.initials: R
authors.lastname: Bai
authors.affiliation: Orthopedics Department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Li
authors.affiliation: Orthopedics Department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Orthopedics Department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Han
authors.initials: H
authors.lastname: Wu
authors.affiliation: Orthopedics Department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Yuqiang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Orthopedics Department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Orthopedics Department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Wenfei
authors.initials: W
authors.lastname: Gao
authors.affiliation: Orthopedics Department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Dong
authors.affiliation: Orthopedics Department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Wensheng
authors.initials: W
authors.lastname: Liao
authors.affiliation: Orthopedics Department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Yilin
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Orthopedics Department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Orthopedics Department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Limin
authors.initials: L
authors.lastname: Wang
authors.affiliation: Orthopedics Department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Weidong
authors.initials: W
authors.lastname: Wang
mesh_terms: D002574:Cervical Vertebrae / Q000601:surgery*; D002648:Child; D002675:Child, Preschool; D005260:Female; D005593:Fracture Fixation, Internal / Q000379:methods; D006801:Humans; D008297:Male; D009333:Neck / Q000601:surgery*; D065289:Pedicle Screws; D011446:Prospective Studies; D012727:Sex Characteristics; D013123:Spinal Fusion / Q000379:methods