# Telehealth Using PoseNet-Based System for In-Home Rehabilitation
## 1 Introduction  
Telehealth refers to the delivery of health-related services including medical care, health education and health information services over a distance via the use of digital information and communication technologies such as computers, laptops and mobile devices [1]. Telehealth was created to overcome the physical barriers in offering healthcare services to patients and caregivers without in-person visits and to reduce the travelling challenges for patients in rural areas [2]. On top of this, rapid ageing of the global population has brought unprecedented and escalating challenges to the healthcare services. According to data provided by the World Health Organization (WHO), the proportion of the global population over the age of 60 will rise from 12% to a staggering 22%, almost doubling from 2015 to 2050 [3]. These elderly, especially those with chronic conditions, are not fit to travel long distance for healthcare services. Therefore, telehealth plays a crucial role in the seamless delivery of an efficient and cost-effective remote healthcare services for these people. In addition, the current COVID-19 pandemic has also induced the rapid adoption of telehealth and instigated adaptation and reform in the delivery of healthcare services [2]. Studies have shown that 90% of patients and parents felt safer using a telehealth virtual appointment compared to an in-person visit during the COVID-19 pandemic [4]. The functionality and scope of the telehealth system are rapidly increasing and well received by patients and clinicians. By leveraging the advantage of telehealth to facilitate remote healthcare services, in-home rehabilitation offers diverse healthcare services to individual households. This covers a range of activities, from assessing the patient's functional ability in his/her environment to specific supervised treatment or exercises [5]. In most countries nowadays, in-home rehabilitation services are strongly supported by the government. The number ofpatients applying for such services has grown significantly, adopting family assessment and occupational therapy to enhance the performance of daily activities [6]. It can be effectively used in physical therapy, such as postoperative knee rehabilitation [7; 8]. As a result, in-home rehabilitation offers a lot of benefits for patients via the use of a telehealth system. Traditionally, patients perform rehabilitation exercises in hospitals or rehabilitation centers. In Malaysia, rehabilitation services are offered by both governmental and non-governmental agencies [9]. Some challenges in these provisions include the lack of coordination among these agencies and severe service barriers for patients in rural areas with poor transportation, or for whom driving is unsuitable because of their medical condition. One way to address this issue is to hire a home therapist who visits the patient's house, but not all patients can afford the higher cost. An alternative solution is to offer in-home rehabilitation services via the use of a telehealth system. Previously, a marker-based system was used for in-home rehabilitation to detect patient's movements by placing markers on their bodies. However, the cost of these marker-based systems is high [10]. An example of a low-cost marker-based system such as Perceptron Neuron is priced at USD$1499 (approximately RM 6000) in Malaysia [11]. According to the Malaysian Department of Statistics, the average monthly household income of the bottom 40% of the population (the B40 group) is below RM 4849, while the average monthly household income of the middle 40% of the population (the M40 group) ranges from RM 4850 to RM 10,959 [12]. Hence, Perceptron Neuron is obviously beyond the reach of the B40 and M40 household income groups in Malaysia. On top of this, professional skill is required to place the markers correctly on the bodies [13]. If the markers are misplaced, it might lead to an inaccurate detection.