Is It Possible to Obtain Reliable MPTA and LDFA Values Using Imageless Navigation in Total Knee Arthroplasty? Comparison Between Preoperative CT Scan Measurements and Intraoperative Bone Morphing Before and After Articular Cartilage Removal

NCT07574775 | Completed

• 1 other identifier: 2025-A00825-44 CAR-NAV-AL
• Study Type: interventional
• Target: 50
• Locations: 1 country
• Sites: 1

Brief Summary

Title: Evaluation of Image-less Navigation Accuracy in Total Knee Arthroplasty (CARNAVAL) Summary: The purpose of this study is to evaluate the accuracy of an imageless navigation system in measuring key anatomical angles (MPTA and LDFA) during Total Knee Arthroplasty (TKA). While preoperative CT scans are currently the gold standard for bone planning, imageless navigation uses a "bone morphing" technique during surgery to create a digital model of the knee. The study aims to determine if the measurements obtained via bone morphing, both before and after cartilage removal, are consistent with the measurements obtained from preoperative CT scans. The investigators seek to confirm if imageless navigation can provide reliable anatomical data, potentially reducing the need for preoperative radiation and costs associated with CT imaging.

Conditions

Arthroplasty; Bone Morphing; Knee Osteoarthritis

Keywords

Lateral Distal Femur Angle (LDFA); Medial Proximal Tibial Angle (MPTA); Imageless navigation; Total Knee arthroplasty

Outcome Measures

Primary Outcomes (1)

• Mean Difference in Medial Proximal Tibial Angle (MPTA) between CT scan and Imageless Navigation.

  The mean difference (measured in degrees) between the MPTA calculated from the preoperative 3D CT scan and the MPTA measured intraoperatively via bone morphing after cartilage removal.

  At the time of surgery (intra-operative).

Secondary Outcomes (2)

• Mean Difference in Lateral Distal Femoral Angle (LDFA) between CT scan and Imageless Navigation.

  At the time of surgery (intraoperative)

• Correlation of MPTA and LDFA measurements before and after cartilage removal.

  At the time of surgery (intra-operative).

Study Arms (1)

Navigation and CT-scan Comparison Group)

EXPERIMENTAL

All participants undergo Total Knee Arthroplasty (TKA) using an imageless navigation system. Anatomical measurements (MPTA and LDFA) are recorded via bone morphing at two stages: 1) on intact articular cartilage and 2) after cartilage removal.

Procedure: Non-image-based Computer-Assisted Navigation with Bone Morphing

Interventions

Non-image-based Computer-Assisted Navigation with Bone Morphing PROCEDURE

Intraoperative surface morphing of the joint surfaces is performed to obtain LDFA and MPTA values. The procedure compares measurements taken on the residual cartilage versus measurements taken directly on the osseous surface after cartilage debridement. These values are then validated against preoperative 3D CT scan data.

Navigation and CT-scan Comparison Group)

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients aged 18 years or older.
• Patients with primary or secondary knee osteoarthritis requiring a Total Knee Arthroplasty (TKA).
• Patients for whom the surgical planning requires a pre-operative 3D CT scan.
• Patients who have been informed about the study and have signed the written informed consent.
• Patients affiliated with or beneficiaries of a social security scheme.

You may not qualify if:

• Revision Total Knee Arthroplasty (re-operation).
• Major bone loss or significant bone deformity that prevents reliable anatomical landmarking.
• History of prior knee surgery that could interfere with the navigation system trackers (e.g., retained hardware in the femur or tibia).
• Pregnant or breastfeeding women.
• Persons deprived of liberty or under legal guardianship.
• Patients with a known allergy to any component used during the standard surgical procedure.

Sponsors & Collaborators

• Groupe Hospitalier Diaconesses Croix Saint-Simon: lead

Study Sites (1)

Groupe hospitalier Diaconesses Croix Saint Simon

Paris, 75020, France

Location

Related Publications (3)

• Blakeney WG, Khan RJ, Wall SJ. Computer-assisted techniques versus conventional guides for component alignment in total knee arthroplasty: a randomized controlled trial. J Bone Joint Surg Am. 2011 Aug 3;93(15):1377-84. doi: 10.2106/JBJS.I.01321.

  PMID: 21915542 BACKGROUND

• MacDessi SJ, Griffiths-Jones W, Harris IA, Bellemans J, Chen DB. Coronal Plane Alignment of the Knee (CPAK) classification. Bone Joint J. 2021 Feb;103-B(2):329-337. doi: 10.1302/0301-620X.103B2.BJJ-2020-1050.R1.

  PMID: 33517740 BACKGROUND

• Rossi SMP, Sangaletti R, Perticarini L, Terragnoli F, Benazzo F. High accuracy of a new robotically assisted technique for total knee arthroplasty: an in vivo study. Knee Surg Sports Traumatol Arthrosc. 2023 Mar;31(3):1153-1161. doi: 10.1007/s00167-021-06800-8. Epub 2022 Jan 4.

  PMID: 34981162 BACKGROUND

MeSH Terms

Conditions

Osteoarthritis, Knee

Condition Hierarchy (Ancestors)

Osteoarthritis; Arthritis; Joint Diseases; Musculoskeletal Diseases; Rheumatic Diseases

Study Officials

• Antoine MOUTON, Orthopedic surgeon

  Diaconesses Croix Saint Simon Hospital Group

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: HEALTH SERVICES RESEARCH
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: This is a prospective, single-group diagnostic accuracy study where each participant serves as their own control. For every patient, anatomical measurements (MPTA and LDFA) are obtained and compared using three different methods: Reference Standard: Preoperative 3D CT scan. Index Test A: Peroperative image-less navigation (bone morphing) performed on intact articular cartilage. Index Test B: Peroperative image-less navigation (bone morphing) performed after complete surgical removal of the cartilage. This intra-subject design allows for a direct comparison of the navigation system's fidelity against the gold-standard CT scan, while specifically isolating the impact of cartilage thickness on measurement accuracy.

Study Record Dates

• First Submitted: April 28, 2026
• First Posted: May 8, 2026
• Study Start: July 7, 2025
• Primary Completion: October 30, 2025
• Study Completion: October 30, 2025
• Last Updated: May 8, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will not share

Locations

FR (1)