Femoral bow predicts postoperative malalignment in revision total knee arthroplasty

J Arthroplasty. 2014 Aug;29(8):1605-9. doi: 10.1016/j.arth.2014.03.002. Epub 2014 Mar 12.

Abstract

Diaphyseal bowing may compromise axial alignment in revision total knee arthroplasty (TKA). 277 patients undergoing revision TKA were evaluated for coronal bowing and hip-knee-ankle (HKA) axis. The mean femoral bow was 1.52° ± 0.18° varus (-10.1° to +8.4°). The mean tibial bow was 1.25° ± 0.13° valgus (-5.9° to +10°). HKA axis averaged 3.08° ± 0.35° varus preoperatively compared to 0.86° ± 0.25° varus postoperatively. Inter-rater and intra-rater reliability was high. Femoral bow greater than 4° significantly correlated with postoperative HKA axis malalignment (r = 0.402, P = 0.008). 39.7% of patients deviated 3° or greater from a neutral mechanical axis with a significant difference in femoral bow (0.94° ± 0.31°, P = 0.003). Diaphyseal bowing clearly has an important effect on postoperative limb alignment in revision TKA.

Keywords: axial alignment in revision total knee arthroplasty; coronal bowing; femoral bow; malalignment; revision total knee arthroplasty.

MeSH terms

  • Ankle Joint / diagnostic imaging
  • Arthroplasty, Replacement, Knee / adverse effects*
  • Bone Malalignment / diagnostic imaging
  • Bone Malalignment / etiology*
  • Bone Malalignment / surgery*
  • Coxa Valga / diagnostic imaging
  • Coxa Valga / etiology
  • Coxa Valga / surgery
  • Diaphyses / diagnostic imaging
  • Femur / diagnostic imaging*
  • Femur / surgery
  • Hip Joint / diagnostic imaging
  • Humans
  • Knee Joint / diagnostic imaging
  • Knee Joint / surgery
  • Postoperative Period
  • Predictive Value of Tests
  • Radiography
  • Reoperation / methods
  • Reproducibility of Results
  • Tibia / diagnostic imaging*
  • Tibia / surgery