Mechanically or Kinematically Aligned Total Knee Prosthesis (BIOMAKA)

Mechanically or Kinematically Aligned Total Knee Prosthesis: Prospective and Comparative Study of Clinical, Stereoradiographic, and Biomechanical Results

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.

Study Overview

• Status: Recruiting
• Conditions: Osteoarthritis, Knee
• Intervention / Treatment: Device: kinematic knee prosthesis; Device: biomechanic knee prosthesis

• Study Type: Interventional
• Enrollment (Estimated): 120
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Charles Rivière, MD; Phone Number: +33 5 56 46 10 40; Email: charles.riviere@bari-arthroplasty.com

Study Locations

• France
  • Mérignac, France, 33700
    • Recruiting
    • Clinique du Sport Bordeaux Merignac
    • Contact: Charles Rivière, MD; Phone Number: +33 5 56 46 10 40; Email: charles.riviere@bari-arthroplasty.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

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 Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: patients with kinematic aligned knee prosthesis	Device: kinematic knee prosthesis; Patients with a kinematically aligned total knee prosthesis and having a post-operative follow-up consultation within at least 1 year after their surgery are consecutively pre-selected according to the eligibility criteria.
Active Comparator: patients with biomechanic aligned knee prosthesis	Device: biomechanic knee prosthesis; A group of patients with a mechanically aligned TKA and scheduled for a follow-up consultation 1 year after surgery will be identified to be matched on the aforementioned criteria (sex, age, BMI).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Biomechanical parameters of knee : spatiotemporal parameters	When walking on flat ground and when going up/down stairs: walking speed	One year after surgery
Biomechanical parameters of knee : Kinematic parameters in the 3 planes of space	dynamic hip-knee-ankle angles during the knee flexion/extension test with and without support	One year after surgery
Biomechanical parameters of knee : joint moments	Unit : Newton meter	One year after surgery
Biomechanical parameters of knee : force	Unit : body weight	One year after surgery
Biomechanical parameters of knee : lever arms		One year after surgery
Symmetry index between the operated limb and the healthy controlateral limb	Comparison between the two limbs	One year after surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Clinical results : Patient-Reported Outcome Measures: Functional score (OXFORD scale)	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	One year after surgery
Clinical results : Patient-Reported Outcome Measures: joint perception score	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)	One year after surgery
Clinical results : Patient-Reported Outcome Measures: pain	visual analog scale (VAS) pain (numerical scale 0-10), 0 is absence of pain and 10 the worst pain possible	One year after surgery
Clinical results : Patient satisfaction	Scale from "not at all satisfied" to "very satisfied"	One year after surgery
Clinical results : range of mobility of the prosthetic knee	Range of motion from hyperextension to flexion (degrees)	One year after surgery
Clinical results : complication rate	Complication rate (percentage) : manipulation under anesthesia, re-operation, revision, previous pain syndrome	One year after surgery
Imaging results : EOS 3D, alignement of the lower limb	measurement of the frontal alignment of the lower limb (hip-knee-ankle and hip-knee-calcaneus angles)	One year after surgery
Imaging results : EOS 3D, orientation of the implants	- 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	One year after surgery
Imaging results : EOS 3D, distance between anterior femoral cortex and prosthetic trochlea	measurement of the distance between the anterior femoral cortex and the prosthetic trochlea	One year after surgery
Imaging results : radiography, evaluation of implant fixation	evaluation of implant fixation (e.g. sealing, border, reactive line)	One year after surgery
Imaging results : radiography, measurement of patellar height	measurement of patellar height (pre- and post-op Caton-Deschamps index comparison)	One year after surgery
Imaging results : radiography, evaluation of the bone structure	evaluation of bone structure (e.g. osteolysis)	One year after surgery

Collaborators and Investigators

• Sponsor: Clinique du Sport, Bordeaux Mérignac

Study record dates

Study Major Dates

• Study Start (Actual): October 5, 2023
• Primary Completion (Estimated): August 31, 2027
• Study Completion (Estimated): September 30, 2027

Study Registration Dates

• First Submitted: November 14, 2023
• First Submitted That Met QC Criteria: December 4, 2023
• First Posted (Actual): December 6, 2023

Study Record Updates

• Last Update Posted (Actual): April 6, 2026
• Last Update Submitted That Met QC Criteria: March 31, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: mechanical alignment; kinematic alignment; total knee prosthesis; biomechanic study
• Additional Relevant MeSH Terms: Musculoskeletal Diseases; Arthritis; Joint Diseases; Rheumatic Diseases; Osteoarthritis; Osteoarthritis, Knee
• Other Study ID Numbers: 2023-A01312-43

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No