Calcaneus Fracture Fixation: Assessing the Adequacy of the Sinus Tarsi Surgical Fixation Technique

Abstract

Category: Trauma; Hindfoot Introduction/Purpose: Intra-articular calcaneus fractures are devastating injuries, and life-changing for patients that develop post-traumatic arthritis, a common outcome. Debate exists as to whether non-operative symptomatic management, or operative treatment, best manages these injuries, partially due to the difficulty of achieving anatomic subtalar joint reduction. Traditionally, a large, lateral extensile incision has been used, plagued with soft tissue complications quoted at rates upwards of 22%. A less invasive incision, the limited sinus tarsi approach (ST-a), has become more common, proposed to lower complication rates without compromising radiographic nor clinical outcomes. The primary purpose of this study was to objectively assess the adequacy of joint reduction along with the associated soft tissue complications using the ST-a and compare it to the standards of the lateral extensile incision. Methods: All calcaneus fractures fixated through the ST-a at our institution were reviewed between March 2017 and Jan 2020. Inclusion criteria included the presence of preoperative and post-operative X-rays and CT scans. Primary outcomes were radiographic measures, including Bohler's angle on X-ray, and the maximum summative step deformity at the posterior facet of the subtalar joint in all three planes on CT scan. Secondary clinical outcomes included soft tissue complications (infection, delayed wound healing) and the need for reoperation. Results: Thirty patients were included with an average age of 48.9 +- 13.9 (n=24 males, n=6 females) and Sanders classification of 2.8. Pre-operatively, the mean Bohler's angle and summative posterior facet step deformity were 5.8 +- 16.6° and 17.2 +- 9.3mm, respectively. These radiographic outcomes were significantly improved postoperatively to 27.2 +- 7.7° and 5.3 +- 2.9mm. Soft tissue complication rates were half that of the comparative extensile approach. Conclusion: Using the ST-a, radiographic joint reduction was acceptable compared to literature standards. There was subsequently a lower incidence of soft tissue complications than previously quoted for the lateral extensile approach. Although technically more demanding, the ST-a is a valuable method for the treatment of intra-articular calcaneal fractures and should be considered when planning operative management of intra-articular calcaneus fractures.