title: Range of motion after computed tomography-based simulation of intertrochanteric corrective osteotomy in cases of slipped capital femoral epiphysis: comparison of uniplanar flexion osteotomy and multiplanar flexion, valgisation, and rotational osteotomies.
abstract: BACKGROUND
  Various osteotomy techniques have been developed to correct the deformity caused by slipped capital femoral epiphysis (SCFE) and compared by their clinical outcomes. The aim of the presented study was to compare an intertrochanteric uniplanar flexion osteotomy with a multiplanar osteotomy by their ability to improve postoperative range of motion as measured by simulation of computed tomographic data in patients with SCFE.
  
  
  METHODS
  We examined 19 patients with moderate or severe SCFE as classified based on slippage angle. A computer program for the simulation of movement and osteotomy developed in our laboratory was used for study execution. According to a 3-dimensional reconstruction of the computed tomographic data, the physiological range was determined by flexion, abduction, and internal rotation. The multiplanar osteotomy was compared with the uniplanar flexion osteotomy. Both intertrochanteric osteotomy techniques were simulated, and the improvements of the movement range were assessed and compared.
  
  
  RESULTS
  The mean slipping and thus correction angles measured were 25 degrees (range, 8-46 degrees) inferior and 54 degrees (range, 32-78 degrees) posterior. After the simulation of multiplanar osteotomy, the virtually measured ranges of motion as determined by bone-to-bone contact were 61 degrees for flexion, 57 degrees for abduction, and 66 degrees for internal rotation. The simulation of the uniplanar flexion osteotomy achieved a flexion of 63 degrees, an abduction of 36 degrees, and an internal rotation of 54 degrees.
  
  
  CONCLUSIONS
  Apart from abduction, the improvement in the range of motion by a uniplanar flexion osteotomy is comparable with that of the multiplanar osteotomy. However, the improvement in flexion for the simulation of both techniques is not satisfactory with regard to the requirements of normal everyday life, in contrast to abduction and internal rotation.
  
  
  METHODS
  Level III, Retrospective comparative study.
authors.affiliation: Department of Orthopaedic Surgery, Inselspital, University Bern, Bern, Switzerland. mamisch@bwh.harvard.edu
authors.forename: Tallal Charles
authors.initials: TC
authors.lastname: Mamisch
authors.forename: Young-Jo
authors.initials: YJ
authors.lastname: Kim
authors.forename: Jens
authors.initials: J
authors.lastname: Richolt
authors.forename: Christoph
authors.initials: C
authors.lastname: Zilkens
authors.forename: Ron
authors.initials: R
authors.lastname: Kikinis
authors.forename: Michael
authors.initials: M
authors.lastname: Millis
authors.forename: Jens
authors.initials: J
authors.lastname: Kordelle
mesh_terms: D000293:Adolescent; D002648:Child; D003198:Computer Simulation; D004839:Epiphyses, Slipped / Q000000981:diagnostic imaging / Q000601:surgery*; D005260:Female; D005269:Femur / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D010027:Osteotomy / Q000379:methods*; D016059:Range of Motion, Articular; D020127:Recovery of Function; D012189:Retrospective Studies; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed / Q000379:methods*