Anatomical Comparative Study of Cutaneous Nerve Injury Risk in Minimally Invasive Calcaneal Osteotomy: Four-Quadrant Sliding Osteotomy vs the Rising Sun Technique.

Background: Calcaneal osteotomy plays a central role in the correction of hindfoot axis deformities, with minimally invasive techniques becoming increasingly established in recent years. For minimally invasive calcaneal osteotomy (MICO), V-shaped osteotomy and the 4-quadrant sliding osteotomy (4Q) are widely used techniques. Toepfer et al recently introduced the so-called rising sun (RS) technique for MICO. In this surgical technique, perforating drillings are performed instead of a sliding osteotomy. The present cadaveric study aimed to compare the risk of cutaneous nerve injury between the RS technique and the established 4Q technique. Methods: A total of 24 human anatomical specimens were used. Eight specimens underwent osteotomy using the 4Q technique. In 16 specimens, the RS technique was performed. Allocation was randomized. Subsequently, the cutaneous nerves of the foot were dissected and stained. The osteotomy plane was then exposed, distances to the dissected nerves were measured using standardized methods. All nerve injuries were recorded. Results: In the osteotomies performed using the 4Q technique, nerve injury occurred in 6 of 45 evaluable nerves (13.3 %). In the osteotomies performed using the RS technique, a total of 3 nerve injuries were identified in the anatomical dissections of 90 evaluable nerves (3.3%). A statistically significant difference was not found ( Conclusion: The new RS technique appears to be a safe method for MICO; however, based on the available numbers, no statistically significant difference in nerve injury rates between the 2 techniques was detected. Complete avoidance of nerve injury does not seem achievable with percutaneous techniques. Further studies, especially in clinically evaluable patients, are desirable to better assess this technique and its potential for broader clinical application.