[Surgical Treatment of Calcaneus Fractures with C-Nail]

PURPOSE OF THE STUDY The calcaneus bone is the largest tarsal bone of a complex shape, the restoration of which after fracturing, often caused by a high-energy injury, is critical. The top priority in treating these fractures is to correctly asses the condition of the surrounding soft tissues that may be further excessively traumatized by inappropriate timing, surgical approach or technique. Even when adhering to all the rules and guidelines, complications in surgical wound healing have been described in up to 16-33% cases when the extended lateral approach was used. Therefore, the development of minimally invasive techniques, approaches and implants are a promise for improvement. One of them is the C-Nail developed by Medin. MATERIAL AND METHODS In the period from 1 January 2014 to 30 March 2017, a total of 25 patients with calcaneus bone fracture treated with C-Nail using the sinus tarsi approach were followed up at our department. Radiological assessment was made in the patients, the fractures were classified by Sanders and Essex-Lopresti classification systems, the Böhler and Gissane angles before and after reduction were measured. The occurrence of postoperative complications in soft tissue healing and complications caused by the C-Nail and the functional outcome according to the Ankle-Hindfoot Score (AOFAS) were tracked. RESULTS Only one complication in wound healing, namely in case of sinus tarsi approach, was reported in this group of patients. In 9 patients, prominence of osteosynthesis material was observed. Of whom in 4 patients a clinically significant prominence into posterior talocalcaneal articulation was present. Severely limited subtalar range of motion was seen in 5 patients, in other three patients ankylosis was observed, or arthrodesis performed. 8 patients experienced mild reduction of subtalar joint range of motion. 6 patients suffered from mild reduction of range of motion in talocrural joint. The functional outcome according to the Ankle-Hindfoot Score (AOFAS) was 89.4 on average. CONCLUSIONS Our so far limited experience with the osteosynthesis of calcaneal fractures using the C-Nail entitles us to claim that this type of osteosynthesis material allows for adequate stability and subsequent healing of a correctly reduced calcaneal fracture. It is an implant inserted by a minimally invasive surgery and the fracture reduction, when mastering the learning curve, can be efficiently performed from sinus tarsi approach. In our group of patients, the number of complications in soft tissue healing was low, which is why we believe that this type of osteosynthesis is another suitable option to treat the comminuted calcaneal fractures. The handling of the implant as such and other osteosynthesis material is safe provided all the rules covered in detail in the discussion are observed. Key words: calcaneal fracture, C-Nail, sinus tarsi approach.