title: [The clinical value of cartilaginous surface and corresponding osseous contour of patellofemoral joint].
abstract: OBJECTIVE
  to investigate if the cartilaginous surface and corresponding osseous contour of the patellofemoral joint match in the axial plane for providing theoretical basis with evaluating alignment of patellofemoral joint and designing the part of patellofemoral joint in knee prosthesis.
  
  
  METHODS
  from January 2009 to March 2010, 9 human cadaver knees were prepared, which chandra of patellofemoral joint didn't degenerate. Each specimen was sectioned in the axial plane at 20° to 30° knee flax. The cross-sections revealed characteristics in the bony anatomy and corresponding articular surface geometry of the patellofemoral joint in the axial plane. Evaluating parameters included osseous patella congruence angle (OPCA), chondral patella congruence angle (CPCA), patella chondral convex point parameter (PCCPP), patella subchondral osseous convex point parameter (PSOCPP), the parameters of the deepest (chondral or osseous) point of the intercondylar sulcus. After that, the osseous and cartilaginous contours and subchondral osseous contours of the patella in the axial plane were analyzed through MRI data of 11 patients who didn't degenerate in patellofemoral joint cartilage. Parameters as same as cadaver knees were compared.
  
  
  RESULTS
  data from specimens of OPCA was (-4.5 ± 1.1)°, CPCA was (0.5 ± 0.8)°, PCCPP was 1.13 ± 0.11, PSOCPP was 1.67 ± 0.14, PCDPIS was 1.35 ± 0.28, PODPIS was 1.38 ± 0.33. Date from MRI of OPCA was (-3.8 ± 1.4)°, CPCA was (0.7 ± 1.0)°, PCCPP was 1.05 ± 0.21, PSOCPP was 1.73 ± 0.18, PCDPIS was 1.41 ± 0.21, PODPIS was 1.37 ± 0.27. The patella exhibited significant differences in the bony vs. chondral anatomy (P < 0.05), but the intercondylar sulcus nearly match in the bony vs. chondral anatomy.
  
  
  CONCLUSIONS
  the cartilaginous surface and corresponding osseous contour of the patella don't match in the patellofemoral joint axial plane, but that of the trochlea nearly matches. This is very important for accurately evaluating alignment of patellofemoral joint because the normal osseous alignment of patellofemoral joint don't represent the normal alignment and helpful for designing the part of patellofemoral joint in knee prosthesis.
authors.affiliation: Department of Joint, the Third Hospital of Hebei Medical University, Shijiazhuang 050051, China.
authors.forename: Jian-Bing
authors.initials: JB
authors.lastname: Zhang
authors.forename: Bai-Cheng
authors.initials: BC
authors.lastname: Chen
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.forename: Zhi-Qiang
authors.initials: ZQ
authors.lastname: Wang
authors.forename: Chang-Bao
authors.initials: CB
authors.lastname: Yan
mesh_terms: D001696:Biomechanical Phenomena; D002358:Cartilage, Articular / Q000033:anatomy & histology*; D005269:Femur / Q000033:anatomy & histology; D006801:Humans; D010329:Patella / Q000033:anatomy & histology; D057071:Patellofemoral Joint / Q000033:anatomy & histology*