Abstract

Knee osteoarthritis (OA) is common, painful, progressive and disabling, and has significant personal and societal burden, particularly in an ageing population. Whilst knee replacement is successful for very late stage disease, it is inappropriate for earlier stages, leaving few effective treatments available for patients in the “treatment gap” between symptom free and late-stage arthritis. High Tibial Osteotomy (HTO) is a proven surgical treatment providing good long-term outcome, reducing pain and improving function. HTO involves changing the alignment of the tibia to correct improper joint loading. Outcomes of HTO surgery are linked directly to the accuracy of the surgical re-alignment with under-correction resulting in worse outcomes. Inaccuracies occur primarily due to limitations of the current planning and surgical technique. A new method (TOKA) has been devised involving personalisation and digital planning. This method uses a custom personalised surgical guide and plate, tailored to the patient.

The aim of the PASHiOn trial is to establish whether digitally planned personalised HTO surgery (TOKA) increases the accuracy of bone correction in comparison to conventional HTO surgery. Embedded within the trial is a nonrandomised pre-RCT technology check and safety assessment of 5 patients (Phase 1), followed by a randomised controlled trial of 88 patients (Phase 2).

During Phase 1 of the clinical investigation, 5 patients fulfilling the inclusion criteria will be recruited and assessed in an identical way to the 88 patients recruited in the main trial, but without randomisation. Recruitment of the remaining patients (Phase 2) will take place after the six-week assessment on the fifth patient is complete and the oversight committee supports progression to Phase 2. Patients in Phase 1 and 2 will be followed up in the same manner for a period of up to 15 months from registration (Phase 1) and randomisation (Phase 2) (12 months from surgery).

Competing Interest Statement

Gill, MacLeod and Toms are named inventors on a related patent

Clinical Trial

NCT04666571

Funding Statement

This study was funded by Versus Arthritis, grant number 22262.

Author Declarations

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

London - Stanmore Research Ethics Committee of the NHS Heath Research Authority gave ethical approval for this work. (IRAS project ID:280261, REC reference:20/LO/1082)

I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.

Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

Yes

I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

Yes

Data Availability

This is the study protocol for the PASHiOn trial and as such data availability is not relevant.

Appendix: glossary of abbreviationsSAPStatistical Analysis PlanDSMCData and Safety Monitoring CommitteeTSCTrial Steering CommitteeCIChief InvestigatorHTOHigh Tibial OsteotomyTOKATailored Osteotomy Knee AlignmentICEIntercurrent EventKOOSKnee injury and Osteoarthritis Outcome ScorePROMPatient Reported Outcome MeasureROMRange of MotionUCLAActivity Score University of Carolina, Los Angeles Activity ScoreVVAVideo Vector AnalysisHKAHip Knee AnkleITTIntention-to-TreatPPPer Protocol