title: [Three-dimensional visualization of intercondylar notch based on MRI two-dimensional images].
abstract: OBJECTIVE
  To study the feasibility of virtual intercondylar notchplasty by applying MRI two-dimensional (2D) images to reconstruct three-dimensional (3D) images and measure the size of intercondylar notch.
  
  
  METHODS
  Thirty healthy volunteers who had no knee joint disease and surgery history were selected. There were 15 females and 15 males with an age range of 20-30 years, weight range of 45-74 kg, and height range of 150-185 cm. They were divided into male group and female group, and the knees of each group were divided into 2 subgroups (the left group and right group). MRI scan of the left and right knees was performed, and the 2D images of MRI were imported into Mimics 10.01 medical image control system for 3D reconstruction. The related anatomical data as follows were measured from the 3D digital model and analyzed by statistical software: notch width (NW), condylar width (CW), and notch width index (NWI). Then the 3D knee images of patients with anterior cruciate ligament (ACL) injury were collected between January and March 2010, and 4 patients with narrow intercondylar notch (NWI < or = 0.2) were selected for reconstructing the 3D model of the knee and simulating the intercondylar notch plasty. Then, the volume of osteotomy in 3D model was calculated and applied in the ACL reconstruction surgery, and whether the graft had impingement with intercondylar notch or not was evaluated.
  
  
  RESULTS
  There were significant differences in NW and CW between male group and female group (P < 0.05), but no significant difference was found in the NWI (P > 0.05). And there was no significant difference in NW, CW, and NWI between the left and right knees both in male group and female group (P > 0.05). After ACL reconstruction and intercondylar notchplasty, the shape of intercondylar notch became normal (NWI > 0.22), no impingement occurred between the graft and intercondylar notch under arthroscopy within 3-month follow-up.
  
  
  CONCLUSIONS
  The shape of intercondylar notch of 3D model based on MRI 2D images is similar to the real intercondylar notch. NWI is one of important indexes which can reflect the narrow level of intercondylar notch. The virtual intercondylar notchplasty may provide preoperative plan and guidence for ACL reconstruction operation to avoid the impingement between graft and intercondylar notch after surgery.
authors.affiliation: Department of Sports Medicine, First Affiliated Hospital of Kunming Medical University, Kunming Yunnan 650032, PR China. yanlinli1969@yahoo.com.cn
authors.forename: Yanlin
authors.initials: Y
authors.lastname: Li
authors.forename: Peng
authors.initials: P
authors.lastname: Xu
authors.forename: Rui
authors.initials: R
authors.lastname: Han
authors.forename: Jianwei
authors.initials: J
authors.lastname: Wang
authors.forename: Chuan
authors.initials: C
authors.lastname: He
authors.forename: Guoliang
authors.initials: G
authors.lastname: Wang
authors.forename: Lu
authors.initials: L
authors.lastname: Tong
authors.forename: Meng
authors.initials: M
authors.lastname: Hu
mesh_terms: D000328:Adult; D016118:Anterior Cruciate Ligament / Q000000981:diagnostic imaging; D000070598:Anterior Cruciate Ligament Injuries; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D005269:Femur / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000601:surgery; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D007718:Knee Injuries / Q000000981:diagnostic imaging / Q000601:surgery*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D011859:Radiography; D012737:Sex Factors; D014584:User-Computer Interface; D055815:Young Adult