Neutral alignment resulting from tibial vara and opposite femoral valgus is the main morphologic pattern in healthy middle-aged patients: an exploration of a 3D-CT database

  • Micicoi Grégoire
  • Jacquet Christophe
  • Sharma Akash
  • Liarno Sally
  • Faizan Ahmad
  • Kley Kristian
  • Parratte Sébastien
  • Ollivier Matthieu

  • Knee
  • Native
  • Alignment
  • HKA
  • MPTA
  • LDFA
  • PPTA
  • JLCA
  • CT
  • HTO concepts
  • Phenotypes

ART

Purpose Given the goal of achieving optimal correction and alignment after knee arthroplasty or high tibial osteotomy, literature focusing on the inter-individual variability of the native knee, tibia and femur with regards to the coronal or sagit-tal alignment is lacking. The aim of this study was to analyse normal angular values in the healthy middle-aged population and determine differences of angular values according to inter-individual features. The first hypothesis was that common morphological patterns may be identified in the healthy middle-aged non-osteoarthritic population. The second hypothesis was that high inter-individual variability exists with regards to gender, ethnicity and alignment phenotype. Methods A CT scan-based modelling and analysis system was used to examine the lower limb of 758 normal healthy patients (390 men, 368 women; mean age 58.5 ± 16.4 years) with available data concerning angular values and retrieved from the SOMA database. The hip-knee-ankle angle (HKA), lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA), posterior distal femoral angle (PDFA), posterior proximal tibial angle (PPTA) and non weight-bearing joint line convergence angle (nwJLCA) were then measured for each patient. Results were analysed for the entire cohort and based on gender, ethnicity and phenotype.