PT  - JOURNAL ARTICLE
AU  - Liam Ives
AU  - Alizée Pace
AU  - Fabian Bor
AU  - Qingshen Jing
AU  - Tom Wade
AU  - Jehangir Cama
AU  - Vikas Khanduja
AU  - Sohini Kar-Narayan
TI  - Conformable and robust force sensors to enable precision joint replacement surgery
AID  - 10.1101/2021.08.19.456934
DP  - 2021 Jan 01
TA  - bioRxiv
PG  - 2021.08.19.456934
4099  - http://biorxiv.org/content/early/2021/08/19/2021.08.19.456934.short
4100  - http://biorxiv.org/content/early/2021/08/19/2021.08.19.456934.full
AB  - Balancing forces within weight-bearing joints such as the hip during joint replacement surgeries is essential for implant longevity. Minimising implant failure is vital to improve patient wellbeing and alleviate pressure on healthcare systems. With improvements in surgery, hip replacement patients are now often younger and more active than in previous generations, and their implants correspondingly need to survive higher stresses. However, force balancing currently depends entirely on surgical skill: no sensors can provide quantitative force feedback within the hip joint’s small, complex geometry. Here, we solve this unmet clinical need by presenting a thin and conformable microfluidic force sensor, which is compatible with the standard surgical process. We optimised the design using finite element modelling, then incorporated and calibrated our sensor in a model hip implant. Using a bespoke testing rig, we demonstrated high sensitivity at typical forces experienced during hip replacements. We anticipate that these sensors will aid implant positioning, increasing the lifetime of hip replacements, and represent a powerful new surgical tool for a range of orthopaedic procedures where force balancing is crucial.Competing Interest StatementL.I., Q.J., V.K., J.C., and S.K.-N. are named inventors on a patent application by Cambridge Enterprise that covers the technology described in this study. S.K-N, V.K. and J.C. are co-founders and directors of ArtioSense Ltd., incorporated to translate and commercialise aspects of this work. V.K. is Consultant for Arthrex and Smith and Nephew Limited.