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Mechanically or Kinematically Aligned Total Knee Prosthesis

Not Applicable
Recruiting
Conditions
Osteoarthritis, Knee
Interventions
Device: kinematic knee prosthesis
Device: biomechanic knee prosthesis
Registration Number
NCT06158646
Lead Sponsor
Clinique du Sport, Bordeaux Mérignac
Brief Summary

The mechanical alignment technique (Mechanical Alignment - MA) of a total knee prosthesis (TKA) was developed with the aim of making the installation of a TKA simple and reproducible, and that the prosthetic biomechanics are acceptable, thus promoting good longevity of implants. This is a technique that does not aim to restore the constitutional anatomy of the knee; bone cuts are systematically made at fixed angles, in the 3 planes of space, in relation to the mechanical axes of the long bones (femur and tibia). This non-personalized implantation technique therefore systematically alters the anatomy, laxity and kinematics of the knee, causing up to 50% of residual symptoms after prosthetic implantation and 20% of dissatisfied patients.

In order to improve the clinical results of TKA, a new, more personalized and physiological technique was developed in 2007, called Kinematic Alignment (KA). This technique aims to restore the pre-arthritic anatomy, unique to each knee. Patients with severe constitutional deformity of the lower limb therefore retain this deformity after kinematic prosthetic replacement. The impact of the alignment technique on the biomechanics of the prosthetic knee remains poorly described. The main objective of this study is therefore to compare knee biomechanics between mechanical TKA and kinematic TKA.

Detailed Description

Not available

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
120
Inclusion Criteria
  • Patient followed as part of a consultation 1 year after TKA placement
  • Adult patient
  • Patient affiliated to a social security system
  • Patient informed of the study and formally included (signing of informed consent) before the first research review
Exclusion Criteria
  • Patient with a contralateral knee prosthesis
  • Patient with another condition (acquired pathology) of the lower limbs (e.g. severe osteoarthritis of the contralateral knee or hip/ankle) and/or of the nervous system (e.g. Parkinson's) which may significantly affect the quality of walking
  • Pregnant patient
  • Patient deprived of liberty by judicial or administrative decision,
  • Adult patient subject to a legal protection measure or unable to express consent

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
patients with kinematic aligned knee prosthesiskinematic knee prosthesis-
patients with biomechanic aligned knee prosthesisbiomechanic knee prosthesis-
Primary Outcome Measures
NameTimeMethod
Biomechanical parameters of knee : spatiotemporal parametersOne year after surgery

When walking on flat ground and when going up/down stairs:

walking speed

Biomechanical parameters of knee : Kinematic parameters in the 3 planes of spaceOne year after surgery

dynamic hip-knee-ankle angles during the knee flexion/extension test with and without support

Biomechanical parameters of knee : forceOne year after surgery

Unit : body weight

Biomechanical parameters of knee : lever armsOne year after surgery
Symmetry index between the operated limb and the healthy controlateral limbOne year after surgery

Comparison between the two limbs

Biomechanical parameters of knee : joint momentsOne year after surgery

Unit : Newton meter

Secondary Outcome Measures
NameTimeMethod
Clinical results : Patient-Reported Outcome Measures: Functional score (OXFORD scale)One year after surgery

OXFORD scale : numerical rating scale used to quantify the power or strength produced by the contraction of a muscle (0-5) ; 5 is maximal strenght

Clinical results : Patient-Reported Outcome Measures: painOne year after surgery

visual analog scale (VAS) pain (numerical scale 0-10), 0 is absence of pain and 10 the worst pain possible

Clinical results : Patient satisfactionOne year after surgery

Scale from "not at all satisfied" to "very satisfied"

Clinical results : complication rateOne year after surgery

Complication rate (percentage) : manipulation under anesthesia, re-operation, revision, previous pain syndrome

Clinical results : Patient-Reported Outcome Measures: joint perception scoreOne year after surgery

Forgotten joint score : joint-specific questionnaire that focuses on the patients' awareness of their prosthetic joint during daily activities ; 0-100 (0 is the worst result and 100 the better result possible)

Clinical results : range of mobility of the prosthetic kneeOne year after surgery

Range of motion from hyperextension to flexion (degrees)

Imaging results : EOS 3D, alignement of the lower limbOne year after surgery

measurement of the frontal alignment of the lower limb (hip-knee-ankle and hip-knee-calcaneus angles)

Imaging results : EOS 3D, orientation of the implantsOne year after surgery

- measurement of the orientation of the implants in the frontal (medial proximal tibial, lateral distal femoral and joint line convergence angles) and sagittal (tibial slope, flexion of the femoral component) planes

Imaging results : EOS 3D, distance between anterior femoral cortex and prosthetic trochleaOne year after surgery

measurement of the distance between the anterior femoral cortex and the prosthetic trochlea

Imaging results : radiography, evaluation of implant fixationOne year after surgery

evaluation of implant fixation (e.g. sealing, border, reactive line)

Imaging results : radiography, measurement of patellar heightOne year after surgery

measurement of patellar height (pre- and post-op Caton-Deschamps index comparison)

Imaging results : radiography, evaluation of the bone structureOne year after surgery

evaluation of bone structure (e.g. osteolysis)

Trial Locations

Locations (1)

Clinique du Sport Bordeaux Merignac

🇫🇷

Mérignac, France

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