Traditional Versus Alternative Alignment in TKR

As many as 20% of patients are unhappy with the results of total knee replacement (TKR). Various changes to surgical technique have tried to address this but have not led to a significant improvement in the numbers of patients satisfied with their operation. Recently, attention has focussed on alignment of the leg. When viewed from the front, a number of people do not start with a straight, mechanically aligned leg. Traditionally, when implanting a knee replacement, the surgeon tries to put the shin bone half of the knee replacement perpendicular to the floor to equalise stresses on the in and outside of the joint. However, this may result in the alignment of the leg changing considerably, straining the soft tissues around the knee and contributing to dissatisfaction with TKR. There has been a move by some surgeons to change practice, and to implant the TKR in a way that replicates the alignment of the patient's own original knee- alternative alignment. Studies looking at alternative alignment have not shown any loss of satisfaction with results of TKR and indeed are showing some signs that in the short term, function of the knee may be better with the new technique. The research team are planning to run a study comparing the knee replacement used in Exeter- the Triathlon- when put in place using traditional alignment versus using the alternative alignment methods. The outcomes will be assessed in various ways including patient satisfaction questionnaires, measuring muscle strength, flexibility around the knee, and by assessments of alignment of the new knee on X-rays and Computerised Tomography scans. The research team will look at short term results for satisfaction and function of the knee, and in the long term look at wear and survivorship to see if patient satisfaction with TKR can be improved.

NCT Number	NCT03196011
Lead Sponsor	Royal Devon and Exeter NHS Foundation Trust Collaborators: Stryker Nordic
Conditions	Osteo Arthritis Knee
Enrollment	126 participants
Start Date	2018-10-23
Primary Completion	2025-10-31 (estimated)
Study Completion	2025-12-31 (estimated)
Updated on ClinicalTrials.gov	2025-01-30