C-Nail® locking nail versus conventional plate for thalamic calcaneal fractures

Background: Surgery for displaced intra-articular calcaneal fractures (DIACFs) is often followed by skin complications that adversely impacts the functional outcomes. Minimally invasive techniques have been developed to decrease the risk of skin complications. The objective of this study was to compare C-Nail® locking-nail fixation to conventional plate fixation for DIACFs.

Hypothesis: C-Nail® fixation restores calcaneal anatomy similarly to conventional plate fixation and decreases the frequency of skin complications compared to conventional plate fixation, while providing satisfactory functional outcomes.

Material and methods: In this case-control study of DIACFs, fixation was with a non-locking plate in 30 patients treated between January 2016 and June 2017 and with the C-Nail® in 25 patients treated between April 2017 and April 2018. Computed tomography was performed before surgery then bilaterally after surgery for measurements of the following calcaneal parameters: height, length, width, joint-surface step-off and inter-fragmentary distance. The values of these parameters were compared between the two groups. Postoperative skin complications were recorded. The functional outcome was assessed by determining the AOFAS score 1 year after the injury.

Results: The two groups showed no significant differences for age, sex or fracture type. Wound healing was delayed in 3 patients in the plate group. The mean postoperative values of the calcaneal parameters were not significantly different between the two groups. The mean AOFAS score was 85.3±10.4 (range, 50-100) in the plate group and 87.0±12.0 (range, 64-100) in the C-Nail® group (p>0.05).

Discussion: Minimally invasive C-Nail® fixation provides similar restoration of calcaneal anatomy as does conventional plate fixation.

Level of evidence: III, retrospective case-control study.