**2. Materials and Methods**

#### *2.1. Population*

Between 2010 and 2022, 432 patients with ankle arthrodesis (278 males and 154 females, mean age: 64 years [range: 27–93 years]) were retrospectively enrolled in this comparative monocentric study. Group A (*n* = 216) underwent TTCA; group B (*n* = 216) underwent TTA. Both groups were equally distributed in terms of demographics (Table 1). All patients were seen during foot surgery consultations at the study center (Figure 1). The diagnosis of end-stage posttraumatic osteoarthritis of the ankle was made on the basis of clinical examination, obligatory weight-bearing radiographs, and computer tomography.


**Table 1.** Patient characteristics.

BMI, body mass index; SEM, standard error of the mean; TTC, Tibiotalocalcaneal Arthrodesis; TT, Tibiotalar Arthrodesis.

**Figure 1.** Study flow chart.

All patients underwent TTCA or TTA at the study center by five surgeons with the same expertise in this type of surgery. The mean follow-up duration for clinical outcomes was 6.2 years (range: 12–154 months). All procedures were performed in accordance with the 1964 Helsinki Declaration and its later amendments. The ethics committee of the institutional review board approved this study (2022-2883-evBO).
