2021 ISAKOS Biennial Congress ePoster
A Randomised Control Trial Assessing Clinical And Radiological Outcomes Of Patient Specific Instrumentation In Total Knee Arthroplasty: 5-Year Outcomes.
Matthew Hampton, MBChB, FRCS (Tr&Orth), Sheffield UNITED KINGDOM
Caroline Blakey, MBChB MD(res)FRCS(T&O), Sheffield UNITED KINGDOM
Simon C Buckley, FRCS (Tr & Ortho), Sheffield, South Yorkshire UNITED KINGDOM
Paul M. Sutton, MBChB, FRCS, FRCS(Tr & Orth), Sheffield, S Yorkshire UNITED KINGDOM
Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, South Yorkshire, UNITED KINGDOM
FDA Status Cleared
Summary
At mid-term follow-up there are no clinical benefits of PSI over traditional cutting block techniques for routine TKA. There was no significant difference in the radiological measurements of alignment between the groups.
ePosters will be available shortly before Congress
Abstract
Introduction
Patient specific instrumentation (PSI) in Total Knee Arthroplasty (TKA) was developed with the intention of providing more accurate component alignment and improving clinical outcomes. Despite the aims of this technology early studies have shown no improvement in radiological alignment or short-term clinical outcomes, however, there remains a paucity of longer-term clinical outcome studies of this technique.
We compared the clinical and radiologic outcomes of a blinded, randomised trial comparing total knee arthroplasty performed using PSI and a traditional cutting block technique after a minimum of 5-years follow-up.
Materials And Methods
A sample size of 22 in each group was determined as sufficient to detect a difference of 2° in coronal femoral alignment and a clinically significant outcome difference using a power of 80% and
Significance
level of 5%. This number was increased to allow for participant loss and between 2013 and 2016, eighty patients with symptomatic arthropathy of the knee were randomised to undergo Total Knee Arthroplasty using PSI or conventional cutting blocks.
Patients and assessors were blinded to the technique used and outcomes were measured by comparing pre-operative and post-operative EQ-5D, Oxford knee scores (OKS), international knee society scores and radiological measurement of coronal alignment.
Results
Baseline demographics and clinical outcome scores were matched between groups. At a minimum of 5 years following surgery there were 38 knees in the PSI group and 39 in the standard instrumentation group for analysis. This demonstrated there were statistically and clinically significant improvements from baseline in EQ-5D, OKS and IKSS in both groups but no difference between groups.
There was no significant difference in the radiological measurements of alignment between the groups: Coronal femoral angle (P=0.59), coronal tibial angle (P=0.37), tibiofemoral angle (P=0.99), sagittal femoral angle (P=0.34) and posterior tibia slope (P=0.12).
Conclusion
At mid-term follow-up there are no clinical benefits of PSI over traditional cutting block techniques for routine TKA.
Further studies are needed to compare long term survivorship between the two techniques and the use of PSI in complex arthroplasty surgery, for example after previous femoral fracture.