Personalised HTO Versus Generic HTO Virtual Clinical Trial

• ClinicalTrials.gov Identifier: NCT03419598
• Recruitment Status: Completed
• First Posted: February 5, 2018
• Results First Posted: December 7, 2020
• Last Update Posted: December 7, 2020
• Sponsor: University of Bath
• Collaborator: Royal Devon and Exeter NHS Foundation Trust
• Information provided by (Responsible Party): Richie Gill, University of Bath

Tracking Information

• First Submitted Date: January 26, 2018
• First Posted Date: February 5, 2018
• Results First Submitted Date: October 5, 2019
• Results First Posted Date: December 7, 2020
• Last Update Posted Date: December 7, 2020
• Actual Study Start Date: January 3, 2017
• Actual Primary Completion Date: June 28, 2019 (Final data collection date for primary outcome measure)

Current Primary Outcome Measures (submitted: November 11, 2020)

Mechanical Stress in Plate During Gait [ Time Frame: 6 weeks simulated post-operation ]

Mechanical stress (Von Mises) calculated for functional loading using finite element analysis

Original Primary Outcome Measures (submitted: January 26, 2018)

Mechanical stress in plate [ Time Frame: 6 weeks simulated post-operation ]

Mechanical strain calculated for functional loading using finite element analysis

Current Secondary Outcome Measures (submitted: November 11, 2020)

Mechanical Strain in Bone Around Screws During Gait [ Time Frame: 6 weeks simulated post-operation ]

Mechanical strain calculated for functional loading using finite element analysis, note strain is dimensionless and hence has no units

Original Secondary Outcome Measures (submitted: January 26, 2018)

Mechanical strain in bone around screws [ Time Frame: 6 weeks simulated post-operation ]

Mechanical strain calculated for functional loading using finite element analysis

• Current Other Pre-specified Outcome Measures: Not Provided
• Original Other Pre-specified Outcome Measures: Not Provided

Descriptive Information

• Brief Title: Personalised HTO Versus Generic HTO Virtual Clinical Trial
• Official Title: Personalised Subject Specific HTO Versus Generic HTO Virtual Clinical Trial

Brief Summary

High Tibial Osteotomy (HTO) is an alternative to knee replacement in suitable patients with early knee osteoarthritis (OA), it is particularly suited to patients with single compart disease who otherwise would be suitable for unicompartmental knee replacement (UKR). OA of the knee is very common and increasing driven by the ageing of the population. The current limitations of HTO are related to the difficulty of achieving the desired correction due to a challenging surgical technique and soft tissue irritation due to the use of generic stabilisation plates. This study will examine the safety equivalence of a new patient specific HTO process which has patient specific 3D printed plates, i.e. personalised HTO plates, with the existing most commonly used HTO procedure using the Tomofix generic HTO plate. Importantly this study will be undertaken as a Virtual Trial, existing anonymised 3D imaging data will be used to create the virtual patient cohort. This cohort will receive both procedures, which for this type of procedure is only possible in a virtual scenario.

The main question to be addressed is: "Is the personalised HTO procedure as safe as the most commonly used existing generic HTO procedure?". In this context safety concerns the mechanical loads placed upon the tibia and the support plate.

The interventions will all be made on computer models, the 3D imaging data will be used to create the intact (un-operated) models of the subject tibias. Each model will then be virtually operated upon, with both the personalised and generic HTO procedures. The models will then be loaded with physiological loads experienced during function and the mechanical states compared.

Detailed Description

Ethical approval was obtained to use CT scans of 30 patients with moderate to severe knee arthritis (REC reference: 17/HRA/0033, Royal Devon & Exeter National Health Service [NHS], UK).

The CT data will be used to generate the 3D geometry of each patient's proximal tibia. The osteotomy correction angle required for each patient such that the altered mechanical axis will pass through a point 62.5% of the distance from medial to lateral tibial plateau. Virtual HTO surgery will be performed on each patient to alter the mechanical axis of the knee by creating an opening wedge osteotomy.

After the virtual surgeries are performed, each virtual patient will be duplicated. One copy will have the osteotomy stabilised using a Generic plate and the other using a Personalised plate, thus forming the two arms of the trial.

For each participant in each arm finite element (FE) models will be created, and loads applied simulating walking, sit to stand and squatting. Four healings stages will be considered, stage 1 being immediately post-operation (this will not be modelled), stage 2 representing 2 weeks post-operation, stage 3 representing 6 weeks and stage 4 representing 12 weeks. The mechanical loads in the plates, and around the screw locations in the bone, will be established by solving these finite element models.

• Study Type: Observational
• Study Design: Observational Model: Case-Control; Time Perspective: Prospective
• Target Follow-Up Duration: Not Provided
• Biospecimen: Not Provided
• Sampling Method: Non-Probability Sample
• Study Population: Population was recruited from waiting list of patients with knee OA
• Condition: Osteoarthritis, Knee

Intervention

• Procedure: Opening wedge high tibial osteotomy
  Realignment of knee by creating an opening wedge osteotomy in the upper part of the tibia. Since this is a virtual trial, the virtual patients were duplicated and enrolled into both arms
  Other Name: HTO
• Device: Personalised subject specific custom HTO plate
  Subject specific custom plate for stabilizing an open wedge HTO
  Other Name: Personalised plate
• Device: Generic HTO plate
  Generic plate for stabilizing an open wedge HTO
  Other Name: Generic plate

Study Groups/Cohorts

All study participants

All virtual participants who received a virtual opening wedge high tibial osteotomy. The baseline information was the individual CT-based geometry of tibia.

Interventions:

• Procedure: Opening wedge high tibial osteotomy
• Device: Personalised subject specific custom HTO plate
• Device: Generic HTO plate

• Publications *: Not Provided

Recruitment Information

• Recruitment Status: Completed
• Actual Enrollment (submitted: November 11, 2020): 30
• Original Estimated Enrollment (submitted: January 26, 2018): 20
• Actual Study Completion Date: June 28, 2019
• Actual Primary Completion Date: June 28, 2019 (Final data collection date for primary outcome measure)

Eligibility Criteria

Inclusion Criteria:

• Appropriate existing CT data of lower limb.
• Male or Female, aged 18 years or above.
• Diagnosed with moderate to severe OA of the knee.

Exclusion Criteria:

• Abnormal anatomy of tibia or presence of pathology other than OA, e.g. bone tumour.
• Previous knee or osteotomy surgery.
• Presence of metal-work

Sex/Gender

• Sexes Eligible for Study: All

• Ages: 18 Years to 65 Years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Contacts: Contact information is only displayed when the study is recruiting subjects
• Listed Location Countries: United Kingdom

Administrative Information

• NCT Number: NCT03419598
• Other Study ID Numbers: RG433_TVT003
• Has Data Monitoring Committee: No

U.S. FDA-regulated Product

• Studies a U.S. FDA-regulated Drug Product: No
• Studies a U.S. FDA-regulated Device Product: No

IPD Sharing Statement

• Plan to Share IPD: No
• Plan Description: Virtual cohort may be re-used for further studies, all virtual patients are anonymized

• Current Responsible Party: Richie Gill, University of Bath
• Original Responsible Party: Same as current
• Current Study Sponsor: University of Bath
• Original Study Sponsor: Same as current
• Collaborators: Royal Devon and Exeter NHS Foundation Trust

Investigators

• Principal Investigator: Richie Gill, DPhil; University of Bath
• Principal Investigator: Andrew Toms, MD; Royal Devon & Exeter NHS Trust

• PRS Account: University of Bath
• Verification Date: November 2020