Minimally invasive treatment of calcaneal fractures based on 3D fluoroscopic robot-assisted percutaneous reduction and screw fixation combined with a novel circular distractor.

Abstract

To introduce a surgical technique and evaluate the clinical outcome of minimally invasive treatment of calcaneal fractures based on 3D fluoroscopic robot-assisted percutaneous reduction and screw fixation combined with a novel circular distractor. Design: Retrospective case series. Single Level-1 trauma center. Adult patients with calcaneal fractures (OTA/AO 82C, Sanders type II, III) who were treated with 3D fluoroscopic robot-assisted percutaneous reduction and screw fixation combined with a novel circular distractor from January 2022 to June 2024 were included. Demographic characteristics, operative information, radiological and functional outcomes, and complications. Forty-seven patients (43 men and 4 women, 52 fractures) with a mean age of 46.5±12.2 years (range: 24-73), a mean weight of 73.4±13.0 kg (range: 55-106), and a mean height of 170.1±6.4 cm (range: 150-180) were followed for an average duration of 20.4 months (range: 9-36 months). According to the Sanders classification, there were 39 type II and 13 type III fractures. Based on the Essex-Lopresti classification, 25 fractures were tongue-type and 27 were joint depression-type. The average time from injury to surgery was 8.7±4.2 days (range: 2-18), and the mean operative duration was 86.8±33.9 minutes (range: 45-180).Postoperative radiographic parameter assessment revealed significant restoration of the calcaneal anatomy, with a marked reduction in width (from 47.8±4.6 mm to 43.4±4.2 mm, P < 0.001) and significant improvements in height (from 39.3±4.8 mm to 46.2±4.0 mm, P < 0.001) and length (from 79.2±5.9 mm to 81.6±5.1 mm, P < 0.001). Furthermore, both Böhler's angle (from 7.4±13.5° to 25.4±9.2°, P < 0.001) and Gissane's angle (from 119.3±13.4° to 113.4±10.1°, P < 0.001) were significantly corrected. The vertical articular step significantly decreased from 4.3±0.8 mm before the operation to 0.9±0.5 mm (P < 0.001). There were no wound complications. At the final follow-up, the mean Maryland Foot Scale (MFS), American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, and visual analogue scale (VAS) score were 93.5±6.4, 91.3±7.6, and 1.0±1.0, respectively. No patients required secondary surgery, except for five patients for whom the internal fixation was removed. This study demonstrated favorable clinical outcomes for the minimally invasive treatment of calcaneal fractures using 3D fluoroscopic robot-assisted percutaneous reduction and screw fixation in combination with a novel circular distractor. This surgical protocol is suggested to be both safe and reliable on the basis of this findings. Therapeutic Level IV.