Bionic plate design for calcaneal fracture treatment. A biomechanical analysis and first clinical results.

Purpose: Calcaneal fracture treatment is challenging. Implant failure is one problem encountered with plate osteosynthesis. Therefore a new "bionic" plate was developed, which imitates the trabecular orientation of the human calcaneus. The aim of this study was to biomechanically test this new plate in comparison to a "standard" calcaneal locking plate and present the first clinical results.

Methods: Six "bionic" and six "standard" calcaneal plates were biomechanically tested for stability and fatigue using synthetic calcanei. Between 4/2012 and 04/2013 the first ten consecutive patients meeting the inclusion criteria were treated with the novel implant and followed-up clinically and radiologically. The 12-month follow-up results are reported.

Results: The "bionic" plate design showed significantly higher fatigue life (68%), load to failure (100%) and reduced displacement under load (90%) if compared to a "standard" locking plate. No major complications were seen; most notably there was no implant failure and no loss of reduction. Mean AOFAS/hindfoot score was 79 (69-86).

Conclusions: The novel plate architecture offers higher stability and load tolerance while being more resistant to fatigue. The preliminary clinical results are promising. These findings will have to be proved by larger clinical trials.