A new navigation system for radius osteotomy surgery based on holographic computing: An in vitro study

The use of surgical navigation using holograms provided by mixed reality glasses is already a reality in other fields of orthopaedics as the shoulder or knee. Due to this, this study aimed to develop and evaluate a mixed reality-based system for navigation in derotational radius osteotomies, focusing on its accuracy and reproducibility. To this end, a holographic computing software based on C++ language and code integrable in MRTK 2 (Microsoft, Redmond, USA) was generated to be implemented in Microsoft Hololens 2. Using the 3D Builder software, positioners and trackers, recognisable by mixed reality glasses, were designed and patented, allowing us to know the changes in spatial relationship between two trackers. A total of 41 radius biomodels were used. A hand surgery consultant and an orthopaedics resident each performed ten rotational osteotomies using freehand technique and ten with the navigation system. Afterwards, a CT scan was performed, measuring the variation achieved. The error was defined as the difference between the planned and obtained orientation in both techniques and analyzed statistically. Under these conditions, the median error of the navigated system was 1º [0-2.25°], compared to 11º [7-19.5°] with the freehand technique (p<0.05). Error did not significantly increase with greater osteotomy magnitudes. The navigated system demonstrated higher accuracy and reproducibility. No significant inter-surgeon differences were observed in either technique. In conclusion, surgical navigation based on holographic computerization improves the accuracy of radius rotational osteotomies. Due to its reproducibility and simplicity, it represents a potential technique for future surgical navigation.