# Applying Vision-Based Pose Estimation in a Telerehabilitation Application
## 1 Introduction  
With a considerable increase in the number of chronic, disabled or mobility-impaired patients, virtual rehabilitation stands out as a modern alternative to treat these patients through the use of virtual reality, augmented reality and motion capture technologies. In this type of rehabilitation, patients undergo a virtual environment in which they develop the exercises corresponding to their treatment. In addition, at the present time in which we live, the pandemic of the COVID-19 disease triggered by the SARS-CoV-2 virus has caused an unprecedented crisis in all areas, with the health sector being among the sectors that have suffered the most. Understandably, many healthcare providers are now more focused on attending to the urgent and life-threatening health needs of people. One of the main measures that have been taken worldwide in the face of the pandemic situation experienced has been the reduction of face-to-face activities at all levels, which has given rise to three main fields of action: implementation of an online consultation modality or remote, for which use is made of different platforms (technological or nontechnological) and formats; mobilization and support of health personnel; and attention to the health and well-being of patients. In this context, the use of technologies that allow telecare, including rehabilitation treatments, is offering a safe alternative, and in many cases, the only possible one. On the other hand, given the lack of motivation of patients to accomplish treatment at home, a new methodology based on gamification has begun to be used. Incorporating an element of entertainment through gamification of these activities can stimulate the patient to perform the activities while playing the game. These types of games that include physical activity are called \"exergames\" [1, 2, 3]. This new methodology makes use of exergames, which allows the patient's motivation in the realization of telerehabilitation exercises to be increased. Exergames aim to stimulate the mobility of the body through the use of interactive environments with immersive experiences that simulate different sensations of presence and require physical effort toplay [4]. Research indicates that they can produce improvements in fitness [5], posture [6], cognitive function [7], balance [8] and other nonphysical effects [9]. The fact that exergames are presented as games and gamify tasks provides the extra potential to increase motivation; therefore, the continuity of exercise or rehabilitation programs by patients. Consequently, diverse exergames have been successfully applied to medical conditions such as stroke [10], autism [11] or motor function impairments [12; 13], among many others. There are different examples in the literature about the use of exergames in telerehabilitation [14]. Some of them have adopted tools and technologies of video consoles to manage the monitoring of patient movements. In this sense, we can find works such as [15; 16; 17], where they make use of the Microsoft Kinect sensors [18] of the Xbox console. This sensor allows the movements of the patient to be monitored in a 3D space, allowing the patient to interact with the application directly with their body, without using additional controls. In [19; 20; 21], they use the Wii remote or the Wii Balance Board of the Nintendo Wii console, although in these cases, the use of patient control devices is necessary. In [22; 23; 24], virtual reality systems are used with promising results in rehabilitation, although they are different technologies from those proposed. They are of interest to the work because they make use of gamification and vision systems. In these referenced works, it has been necessary to use sensors such as LeapMotion, VR glasses (for example, Oculus Quest) and other complex sensors to visualize and track movements. In recent years, these methodologies have been complemented with other technologies such as virtual reality.