In-vivo evaluation of the kinematic behavior of an artificial medial meniscus implant: A pilot study using open-MRI

Clin Biomech (Bristol, Avon). 2014 Sep;29(8):898-905. doi: 10.1016/j.clinbiomech.2014.07.001. Epub 2014 Jul 17.

Abstract

Background: In this pilot study we wanted to evaluate the kinematics of a knee implanted with an artificial polycarbonate-urethane meniscus device, designed for medial meniscus replacement. The static kinematic behavior of the implant was compared to the natural medial meniscus of the non-operated knee. A second goal was to evaluate the motion pattern, the radial displacement and the deformation of the meniscal implant.

Methods: Three patients with a polycarbonate-urethane implant were included in this prospective study. An open-MRI was used to track the location of the implant during static weight-bearing conditions, within a range of motion of 0° to 120° knee flexion. Knee kinematics were evaluated by measuring the tibiofemoral contact points and femoral roll-back. Meniscus measurements (both natural and artificial) included anterior-posterior meniscal movement, radial displacement, and meniscal height.

Findings: No difference (P>0.05) was demonstrated in femoral roll-back and tibiofemoral contact points during knee flexion between the implanted and the non-operated knees. Meniscal measurements showed no significant difference in radial displacement and meniscal height (P>0.05) at all flexion angles, in both the implanted and non-operated knees. A significant difference (P ≤ 0.05) in anterior-posterior movement during flexion was observed between the two groups.

Interpretation: In this pilot study, the artificial polycarbonate-urethane implant, indicated for medial meniscus replacement, had no influence on femoral roll-back and tibiofemoral contact points, thus suggesting that the joint maintains its static kinematic properties after implantation. Radial displacement and meniscal height were not different, but anterior-posterior movement was slightly different between the implant and the normal meniscus.

Keywords: Displacement; Kinematics; Meniscus; Open MRI; Polycarbonate-urethane implant.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Biomechanical Phenomena
  • Female
  • Femur
  • Humans
  • Knee Injuries / surgery*
  • Knee Joint / surgery
  • Knee Prosthesis*
  • Magnetic Resonance Imaging
  • Male
  • Menisci, Tibial / surgery*
  • Middle Aged
  • Pilot Projects
  • Polycarboxylate Cement / chemistry
  • Prospective Studies
  • Prostheses and Implants
  • Range of Motion, Articular
  • Urethane / chemistry
  • Weight-Bearing

Substances

  • Polycarboxylate Cement
  • polycarbonate
  • Urethane