title: A prospective comparison of computer-navigated and fluoroscopic-guided in situ fixation of slipped capital femoral epiphysis.
abstract: BACKGROUND
  Slipped capital femoral epiphysis (SCFE) is usually treated with percutaneous in situ screw fixation to prevent further progression of deformity. The purpose of this investigation is to compare computer navigation (CN) techniques with traditional fluoroscopic (fluoro) techniques for in situ fixation of SCFE.
  
  
  METHODS
  This study was an IRB-approved prospective study of 39 hip pinnings in 33 children. CN techniques were used in 22 cases and fluoro in 17. The CN and fluoro groups were statistically similar in terms of grade and acuity of the slip. Children were assigned to the groups based on the intraoperative imaging technique used by the attending on call, with 3 surgeons in each group taking equal amounts of call. The "approach-withdraw" technique was used in all cases. Postoperative limited-cut, reduced-dose computed tomography (CT) scans were obtained to evaluate screw placement. This included blinded analysis for screw penetration of the joint, screw tip-to-apex distance, the distance the screw passed to the center of the physis, and attainment of center-center position. The number of pin passes, intraoperative radiation exposure, and operating room (OR) time were also analyzed. Statistics used included ANOVA, the χ and median tests.
  
  
  RESULTS
  Compared with the fluoro group, CN resulted in more accurate screw placement. There was 1 case of joint penetration in the fluoro group not appreciated intraoperatively but detected on postoperative CT. CN also resulted in statistically significant (P < 0.05) reduced screw tip-to-apex distance and distance to the center of the physis. There was no statistically significant difference between the 2 groups in attainment of the center-center position, number of pin passes, or intraoperative radiation exposure. OR time averaged 19 minutes longer in the CN group. There was no case of avascular necrosis or chondrolysis in either of the groups.
  
  
  CONCLUSIONS
  Compared with traditional fluoro techniques, CN in situ fixation of SCFE results in more accurate screw placement, comparable number of pin passes and intraoperative radiation exposure, and increased OR time. The cost-benefit ratio of this technology requires careful consideration at each individual institution.
  
  
  METHODS
  II.
authors: Center for Orthopedics and Sports Medicine, Akron Children's Hospital, Akron, OH 44308, USA.
authors: Kenneth T
authors: KT
authors: Bono
authors: Michael D
authors: MD
authors: Rubin
authors: Kerwyn C
authors: KC
authors: Jones
authors: Patrick M
authors: PM
authors: Riley
authors: Todd F
authors: TF
authors: Ritzman
authors: William C
authors: WC
authors: Schrader
authors: Paul
authors: P
authors: Fleissner
authors: Richard P
authors: RP
authors: Steiner
authors: Melanie A
authors: MA
authors: Morscher
authors: Mark J
authors: MJ
authors: Adamczyk
mesh_terms: D000704:Analysis of Variance; D001863:Bone Screws; D002648:Child; D005260:Female; D005471:Fluoroscopy / Q000379:methods; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D061646:Operative Time; D019637:Orthopedic Procedures / Q000379:methods*; D011446:Prospective Studies; D011829:Radiation Dosage; D060048:Slipped Capital Femoral Epiphyses / Q000601:surgery*; D025321:Surgery, Computer-Assisted / Q000379:methods*