## 4 Discussion  
Proprioception, the body's ability to sense its position in space, plays a critical role in maintaining balance and preventing falls. This is particularly important in the context of Total Ankle Replacement (TAR), as changes to the joint structure could potentially impact proprioceptive function. While the specific impact of TAR on proprioception has not been extensively studied, it is reasonable to hypothesize that the procedure could have both positive and negative effects. On one hand, the correction of joint deformities and the relief of pain could potentially improve proprioceptive function by allowing for more normal movement patterns. On the other hand, the alteration of the joint structure could potentially impair proprioception. The study by [PERSON] and [PERSON] [29] highlights the importance of proprioception in the elderly population and the potential impact of age-related declines in somatosensory function. While this study does not specifically address TAR, it underscores the importance of considering proprioceptive function in the management of orthopedic conditions in the elderly population. Since mechanoreceptors in musculotendinous and capsuloligamentous structures respond to the re-establishment of joint space and soft-tissue tensioning after Total Knee Arthroplasty (TKA) and Total Hip Arthroplasty (THA), a study [14] evaluated if in the ankle the damaging of the receptor were caused by the excision of the capsule, weakness of ankle plantar flexors, restricted range of motion, and altered weight bearing. No evidence was found supporting the presence of deficits in proprioception despite capsuleectomy during Total Ankle Arthroplasty (TAA). In addition to that, another study [30] showed that with an anterior surgical approach, no proprioceptive deficit was caused compared to the contralateral ankle in patients evaluated using a specially constructed servo-controlled device. The Delos Postural Proprioceptive System (DPPS) used in this study evidenced that the parameters, both pre- and post-operative in the Osteoarthritis (OA) ankle, are evidently inferior, in a statistically significant way, compared to the healthy contralateral limb, in terms of autonomy and SI. In the OA ankle, it has been evidenced that the proprioceptive stability is reduced, with increased postural waving in support and increased latency in the responses to external mechanical perturbations [30]. In addition, post-traumatic etiologies are frequent, where past acute or chronic and repeated trauma may have contributed to the damage to the mechanoreceptor structures of the joints [31]. The data recorded by DPPS, precise and already validated for the ankle [20], confirm the interesting effect that prosthetic replacement has shown on post-operative stabilometric/proprioceptive control in these patients. The reduction in post-operative mean values compared to pre-operative values (ankle affected by OA), although smaller than expected and not statistically significant, may indicate how the prosthetic replacement of joint surfaces affects the kinesthetic feedback mechanisms in some way. Moreover, in the ankle, the standard implantation of the components does not affect the ligamentous complex of the joint but \"only\" the resection of the osteochondral surfaces. This differs from the total replacement of the knee, which is more studied regarding proprioceptive control, although with opinions and conflicting evidence. Some authors have reported a post-operative reduction in proprioceptive control following the implantation of prosthetic models PS (posterior-stabilized), characterized by the sacrifice of the ligamentous components of the central pivot of the knee [32], while other authors found no differences in proprioceptive control between PS and CR (cruciate-retaining) [1,33].