Assessment of clinical outcomes after reduction of depressed calcaneal fractures using the push-out molding technique.

Introduction: As minimal invasive techniques for depressed calcaneal fracture treatment have become more common, great progress has been achieved with various surgical methods. While these techniques are still currently utilized, new methods have been developed. This study aimed to report the radiologic and clinical outcomes of depressed calcaneal fracture treatment with the "push-out molding" technique and to propose its clinical utility. Materials and methods: From March 2009 to October 2020, a retrospective study was conducted with 52 patients, who received the "push-out molding" technique to treat depressed intra-articular calcaneal fractures (Sanders type II, III, IV). Exclusion criteria were as follows: patients with bilateral calcaneal fractures, open fractures, and a follow-up period <12 months. Radiologic parameters were assessed at following periods: preoperative, postoperative, 3-month follow-up, and last follow-up. Limitation of range of motion (ROM), subjective satisfaction, and complications were assessed at the last follow-up period. Repeated measures ANOVA was used to analyze values at preoperative, postoperative, 3-month, and last follow-up periods. Results: Significant differences in the talo-calcaneal angle (p < 0.001), Böhler's angle (p=<0.001), Gissane's angle (p = 0.023), distance from the lower cortical border of calcaneus to the anterior (p=<0.001) and posterior (p=<0.001) points of posterior articular surface, calcaneal length (p = 0.019), and talo-calcaneal height (p=<0.001). Postoperatively, the posterior articular surface was well maintained, while 21.2% retained a ROM limitation by 20° or higher. Subjective satisfaction was as follows: excellent (42.3%), good (48.1%), fair (9.6%), and poor (0%). Conclusion: The "push-out molding" is a simple technique with the advantage of not requiring much force to treat depressed calcaneal fractures. It can be used as a beneficial surgical technique with minimal damage to the soft tissue, owing to the reduction from the depressed interior part and less severe ROM limitation.