A comparison of registration errors with imageless computer navigation during MIS total knee arthroplasty versus standard incision total knee arthroplasty: a cadaveric study

*The research took place at St. Michael’s Hospital, University of Toronto, Toronto, Ontario, Canada.

Abstract

Optimal component alignment in total knee arthroplasty has been associated with better functional outcome as well as improved implant longevity. The ability to align components optimally during minimally invasive (MIS) total knee replacement (TKR) has been a cause of concern. Computer navigation is a useful aid in achieving the desired alignment although it is limited by the error during the manual registration of landmarks. Our study aims to compare the registration process error between a standard and a MIS surgical approach. We hypothesized that performing the registration error via an MIS approach would increase the registration process error. Five fresh frozen lower limbs were routinely prepared and draped. The registration process was performed through an MIS approach. This was then extended to the standard approach and the registration was performed again. Two surgeons performed the registration process five times with each approach. Performing the registration process through the MIS approach was not associated with higher error compared to the standard approach in the alignment parameters of interest. This rejects our hypothesis. Image-free navigated MIS TKR does not appear to carry higher risk of component malalignment due to the registration process error. Navigation can be used during MIS TKR to improve alignment without reduced accuracy due to the approach.

Keywords:

• Alignment
• arthroplasty
• imageless navigation
• registration error
• total knee replacement

Declaration of interest

E.H.S. reports personal fees and other from Stryker, personal fees and other from Smith&Nephew, personal fees from Amgen, personal fees from Wright medical, other from Zimmer, other from Synthes, other from Sanofi, grants from CiHR, grants from PSI, grants from OTA, grants from AO, personal fees from Elsevier, outside the submitted work; P.A.G. reports personal fees and non-financial support from Smith&Nephew, outside the submitted work; E.T.D. reports grants and personal fees from Brainlab, outside the submitted work. The other authors report no conflicts of interest.

Notes

*The research took place at St. Michael’s Hospital, University of Toronto, Toronto, Ontario, Canada.