title: Is Obesity in Adolescent Idiopathic Scoliosis Associated With Larger Curves and Worse Surgical Outcomes?
abstract: METHODS
  A multicenter retrospective study of preoperative characteristics and surgical outcomes in adolescent idiopathic scoliosis (AIS).
  
  
  OBJECTIVE
  To determine the effect of obesity on (i) curve magnitude at first presentation to an orthopedic surgeon, and (ii) surgical outcomes.
  
  
  BACKGROUND
  Clinical findings for scoliosis may be less apparent in overweight adolescents. The effect of obesity on curve magnitude at presentation to an orthopedic surgeon has not been studied. It is unclear whether obesity is associated with worse surgical outcomes in AIS.
  
  
  METHODS
  Demographic, radiographic, perioperative, and complications data were collected on AIS patients who had undergone posterior spinal fusion (PSF). Descriptive and inferential analyses were conducted to compare healthy-weight (HW) [body mass index percentile for age (BMI%) ≤ 84], overweight (OW; BMI% ≥ 85), and obese (OB; BMI% ≥ 95) adolescents.
  
  
  RESULTS
  We analyzed 588 patients (454 HW, 134 OW, and 71 OB). In comparison with the HW adolescents, major curve magnitude at presentation to orthopedics was larger in the OW adolescents (49.3° vs. 43.9°) (P < 0.0001) and OB adolescents (50.4° vs. 43.9°) (P = 0.001). The OW and OB groups had increased preoperative major curve magnitude [(59.1° vs. 55.4°) (P = 0.001); (59.9° vs. 55.4°) (P = 0.001)], preoperative minor curve magnitude [(42.2° vs. 37.2°) (P < 0.0001); (43.0° vs. 37.2°) (P = 0.001)], preoperative thoracic kyphosis [(30.8° vs. 25.7°) (P < 0.0001); (33.7° vs. 25.7°) (P < 0.0001)], and surgical time [(307 vs. 276 mins) (P = 0.009); (320 vs. 276 mins) (P = 0.005)] than the HW group.Subgroup analysis of the patients with a minimum 2-year follow-up (n = 245) showed a trend towards a higher complication rate in the OB group (47.8% vs. 28.3%) (P = 0.054). The OB group had significantly more superficial infections than the HW group (13.0% vs. 1.6%) (P = 0.001).
  
  
  CONCLUSIONS
  OW patients with AIS have a larger curve magnitude at presentation to an orthopedic surgeon. OW patients who undergo PSF for AIS have increased surgical times. OB patients may be at higher risk of postoperative complications.
  
  
  METHODS
  3.
authors.affiliation: Department of Orthopedic Surgery, C.S. Mott Children's Hospital, University of Michigan, Ann Arbor, MI.
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Orthopedic Surgery, C.S. Mott Children's Hospital, University of Michigan, Ann Arbor, MI.
authors.forename: Laura
authors.initials: L
authors.lastname: Binkowski
authors.affiliation: Boston Children's Hospital, Boston, MA.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Grzywna
authors.affiliation: Department of Orthopedic Surgery, C.S. Mott Children's Hospital, University of Michigan, Ann Arbor, MI.
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Robbins
authors.affiliation: Department of Orthopedic Surgery, C.S. Mott Children's Hospital, University of Michigan, Ann Arbor, MI.
authors.forename: Michelle S
authors.initials: MS
authors.lastname: Caird
authors.affiliation: Department of Orthopedic Surgery, C.S. Mott Children's Hospital, University of Michigan, Ann Arbor, MI.
authors.forename: Frances A
authors.initials: FA
authors.lastname: Farley
authors.affiliation: Boston Children's Hospital, Boston, MA.
authors.forename: Michael
authors.initials: M
authors.lastname: Glotzbecker
mesh_terms: D000293:Adolescent; D001863:Bone Screws; D005260:Female; D006801:Humans; D007738:Kyphosis / Q000601:surgery; D008297:Male; D009765:Obesity / Q000150:complications*; D011183:Postoperative Complications / Q000209:etiology; D012189:Retrospective Studies; D012600:Scoliosis / Q000209:etiology* / Q000601:surgery*; D013123:Spinal Fusion / Q000379:methods; D013904:Thoracic Vertebrae / Q000601:surgery*; D016896:Treatment Outcome