title: The effect of body mass index on lumbar lordosis on the Mizuho OSI Jackson spinal table.
abstract: METHODS
  Prospective cohort study.
  
  
  OBJECTIVE
  Does the patients' body mass index (BMI) influence the degree of intraoperative lumbar lordosis in patients undergoing operative treatment on the Mizuho Orthopedic Systems Incorporated (OSI) Jackson spinal table?
  
  
  METHODS
  Twenty-four consecutive patients undergoing posterior spinal instrumentation and fusion on the Jackson table, excluding those with sagittal malalignment, underwent standing preoperative and prone intraoperative lateral x-rays. Intervertebral body angle measurements were obtained from L1-S1 using the modified method of Cobb. Changes in angle measurements were compared to BMI using linear regression and ANOVA.
  
  
  RESULTS
  We found a mean lordosis of 52.6° in standing preoperative x-rays compared to a prone position mean lordosis of 61.5° on the Jackson table. The mean change was 8.88° with a range of 0°-18°. A linear association between lordosis and BMI was demonstrated (P < .0022). As BMI increased, so did lordosis (correlation coefficient, 0.59).
  
  
  CONCLUSIONS
  The current study is the first in which a correlation of patient body mass and use of the Jackson table has been evaluated. These data suggest that BMI influences lumbar lordosis on the Jackson table and that care must be used when dealing with a population with large BMI on the Jackson table. [Table: see text] The definiton of the different classes of evidence is available on page 83.
authors.affiliation: Orthopaedic Department, Medical College of Georgia, Augusta, Georgia, USA.
authors.forename: Justin
authors.initials: J
authors.lastname: Bundy
authors.forename: Tommy
authors.initials: T
authors.lastname: Hernandez
authors.forename: Haitao
authors.initials: H
authors.lastname: Zhou
authors.forename: Norman
authors.initials: N
authors.lastname: Chutkan
references.citation: Spine (Phila Pa 1976). 1992 Jan;17(1):112-5
references.pmid: 1536011
references.citation: Spine (Phila Pa 1976). 1988 Oct;13(10):1161-7
references.pmid: 2974626
references.citation: Orthop Clin North Am. 1988 Apr;19(2):383-93
references.pmid: 3282206
references.citation: Spine (Phila Pa 1976). 1983 Sep;8(6):576-84
references.pmid: 6228016