Intra-Operative Experience using Magnetic Resonance Imaging (MRI) Based Patient Specific Cutting Guides during Total Knee Arthroplasty

Abstract

Background. The incidence of malalignment in total knee arthroplasty
(TKA) using conventional instrument has been
reported as high as 25%. A relatively new TKA system involves
the use of a preoperative magnetic resonance image
(MRI) to obtain accurate implant placement more consistently.
For broad acceptance of this new technique, it is
crucial to analyze the initial intra-operative experience. The
specific aim of this study was to evaluate the initial intra-operative
experience of a single surgeon using this new technique.

Methods. A total of 15 knees (12 patients: 6 female and 6
male) were reviewed from TKA procedures using the selected
manufacturer’s patient specific cutting guides between January
2011 and April 2013 at a single institution. Patient demographic
and specific parameters and intra-operative alterations
of component positioning were recorded and evaluated.
Results. The preoperative plan was able to predict correctly the
size of the implanted femoral component in 87% (n = 13) and
tibial component in 80% (n = 12) of the cases. However, 60% (n
= 9) of cases required additional intra-operative corrections on
femoral resection, and 73% (n = 11) required an additional 2 - 4
mm correction on the tibial proximal resection. Twenty percent
(n = 3) required additional tibial varus/valgus correction, but
there were no tibial slope corrections for any of the 15 cases.

Conclusions. The initial intra-operative experience of a single
surgeon using current patient specific cutting guides for a selected
manufacturer to align femoral and tibial components during
TKA has raised some concerns. We agreed with previous studies
that caution should be taken when using patient specific cutting
guides without supportive data. The findings of this study provided
additional evidence to contest the accuracy of patient specific
cutting guides with respect to the initial experience of an orthopaedic
surgeon who is trained in total joint replacement. The
results provided more evidence to assist orthopaedic surgeons
in the decision of whether to use these patient specific systems
versus conventional TKA methods. KS J Med 2016;9(2):22-26.