Does the restoration of the hindfoot alignment correlate with good clinical and functional outcomes in displaced intra-articular calcaneal fractures treated with Calcanail®?

Introduction: Calcaneal fractures are quite common and can lead to serious functional consequences. Minimally invasive percutaneous techniques have reduced the incidence of wound and sepsis complications associated with open reduction and internal fixation. The use of intraosseous internal fixation, such as percutaneous intramedullary nailing, has decreased these complications and yielded good functional outcomes. The aim of this study was to assess the correlation between functional outcomes and the restoration of hindfoot alignment according to the long axial view in calcaneal joint fractures treated with percutaneous intramedullary nailing.

Hypothesis: Internal fixation using percutaneous intramedullary nailing restores hindfoot alignment associated with good functional outcomes.

Materials and methods: This was a retrospective single-center, multi-surgeon study involving 20 cases of displaced intra-articular calcaneal fractures treated with a percutaneous nail device (Calcanail®) between 2018 and 2022, with a minimum follow-up of one year. Among these, 11 were classified as Sanders-II and nine as Sanders-III fractures. The primary endpoint was clinical evaluation using the AOFAS scale (/100) and the investigation of a correlation with the radiographic hindfoot alignment according to the long axial view. NRS pain scores, EFAS functional scores (/24), SF-12 scores, and all complications were recorded. Clinical and radiographic follow-up data were analyzed in comparison to the healthy contralateral side at the final follow-up.

Results: The mean follow-up time was 40.1 months ± 14.0 (13-62). A correlation was found between hindfoot alignment and the AOFAS score (r_s = -0.494, p = 0.026). The NRS at the last follow-up was 1.3 ± 1.9 (0.0-6.0). The mean AOFAS score was 81.8 ± 9.6 (57.0-92.0), and the EFAS score was 17.3 ± 3.7 (4.0-21.0).

Discussion: In our study, the use of internal fixation with percutaneous intramedullary nailing achieved acceptable functional and clinical outcomes, along with the restoration of hindfoot alignment, which correlated with the AOFAS functional score.

Level of evidence: IV; retrospective study.