title: Height Restoration after Balloon Kyphoplasty in Rheumatoid Patients with Osteoporotic Vertebral Compression Fracture.
abstract: METHODS
  Retrospective study.
  
  
  OBJECTIVE
  This study was conducted to compare vertebral body height restoration rate in rheumatoid arthritis (RA) patients who had undergone percutaneous balloon kyphoplasty (KP) with that of control group who had matched age, sex, body mass index, and bone mineral density.
  
  
  BACKGROUND
  There is no report on result of KP in RA patients.
  
  
  METHODS
  Postoperative height restoration rate of RA group consisting of 15 patients (18 vertebral bodies) who had undergone KP due to osteoporotic vertebral compression fracture with a 30% or higher vertebral compression rate between May 2005 and January 2013 were compared to control group consisting of 38 patients (39 vertebral bodies) who had matched age, sex, body mass index, and bone mineral density.
  
  
  RESULTS
  No statically significant difference in age (p=0.846), sex (p=0.366), body mass index (p=0.826), bone mineral density (p=0.349), time to surgery (p=0.528), polymethylmethacrylate injection time (p=0.298), or amount (p=0.830) was found between the RA group and the control group. However, preoperative compression rate in the RA group was significantly (p=0.025) higher compared to that in the control group. In addition, postoperative height restoration rate showed significant correlation with the RA group (p=0.008). Although higher incidence of recollapse occurred in the RA group compared to that in the control group, the difference was not statistically significant (p=0.305).
  
  
  CONCLUSIONS
  Compared to the control group, RA patients showed higher compression rate and higher vertebral restoration rate after KP, indirectly indicating weaker bone quality in patients with RA. Higher incidence of recollapse occurred in the RA group compared to that in the control group, although it was not statistically significant.
authors.affiliation: Department of Orthopedic Surgery, Sung-Ae Hospital, Seoul, Korea.
authors.forename: Seung-Pyo
authors.initials: SP
authors.lastname: Suh
authors.affiliation: Department of Orthopedic Surgery, Hanyang University College of Medicine, Seoul, Korea.
authors.forename: Chul-Woong
authors.initials: CW
authors.lastname: Kim
authors.affiliation: Department of Orthopedic Surgery, Hanyang University College of Medicine, Seoul, Korea.
authors.forename: Young-Hoon
authors.initials: YH
authors.lastname: Jo
authors.affiliation: Department of Orthopedic Surgery, Hanyang University College of Medicine, Seoul, Korea.
authors.forename: Chang-Nam
authors.initials: CN
authors.lastname: Kang
keywords: Balloon kyphoplasty; Height restoration rate; Osteoporotic vertebral compression fracture; Rheumatoid arthritis; Thoracolumbar spine