Bicruciate-retaining total knee arthroplasty reproduces in vivo kinematics of normal knees to a lower extent than unicompartmental knee arthroplasty

Knee Surg Sports Traumatol Arthrosc. 2020 Sep;28(9):3007-3015. doi: 10.1007/s00167-019-05754-2. Epub 2019 Oct 22.

Abstract

Purpose: This study aimed to clarify the natural knee kinematics provided by bicruciate-retaining total knee arthroplasty (BCR-TKA) compared with those of unicompartmental knee arthroplasty (UKA) and normal knees.

Methods: Volunteers and patients who had undergone UKA and BCR-TKA with anatomical articular surface performed squatting motion under fluoroscopy. To estimate the knee's spatial position and orientation, a two-dimensional/three-dimensional registration technique was used. The rotation angle and anteroposterior translation of the medial and lateral sides of the femur relative to the tibia in each flexion angle were directly evaluated using the same local coordinate system and their differences amongst the three groups were analysed using two-way analysis of variance and Bonferroni post hoc pairwise comparison.

Results: From 0° to 10° of flexion, the femoral external rotation angle of BCR-TKA knees was significantly greater than that of normal and UKA knees and the medial side of BCR-TKA knees was significantly more anteriorly located than that of normal and UKA knees. From 40° to 50° of flexion, the medial side of UKA knees was significantly more posteriorly located than that of normal and BCR-TKA knees. From 30° to 120° of flexion, the lateral side of BCR-TKA knees was significantly more anteriorly located than that of normal and UKA knees.

Conclusion: The in vivo kinematics of BCR-TKA knees reproduces those of normal knees to a lower extent than those of UKA knees. Thus, BCR-TKA with anatomical articular surface reproduces in vivo kinematics of normal knees to a lower extent than UKA.

Level of evidence: III.

Keywords: Bicruciate-retaining total knee arthroplasty; Kinematics; Squatting; Unicompartmental knee arthroplasty.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Aged
  • Arthroplasty, Replacement, Knee / methods*
  • Biomechanical Phenomena
  • Case-Control Studies
  • Female
  • Fluoroscopy
  • Humans
  • Image Processing, Computer-Assisted
  • Knee Joint / diagnostic imaging*
  • Knee Joint / physiology*
  • Male
  • Range of Motion, Articular / physiology*
  • Rotation