# Personalization of the 3D-Printed Upper Limb Exoskeleton Design--Mechanical and IT Aspects
## 5 Discussion
In weakened people, the use of exoskeletons is less energy-intensive and burdening to the cardiovascular systemthan traditional therapy, but the effectiveness depends on the type of exoskeleton, the type of activity and the effort involved [58]. Studies of exoskeleton-assisted movement are increasingly analyzed using fixed and random effects meta-analysis models. As a result, risks are reduced due to newer generations of exoskeletons and improved patient eligibility criteria [59]. Exoskeletons are a safe, practical, easy-to-learn, non-burdening to working memory and low-intensive method of rehabilitation [60]. Impaired function of the upper extremities results in patients experiencing limited dexterity, both in activities requiring one hand, especially with deficits in the dominant hand, and requiring the use of both hands, which reduces independence in daily life [21]. The proposed solution allows to objectively evaluate both the movement of the hand (healthy and with deficits of different types and levels), the exoskeleton itself and the hand (healthy, with deficits) in the exoskeleton. This makes it possible to compare the results of movement assessment so far carried out by specialists on the basis of their knowledge and experience, and sometimes differing in assessment, among other things, under the influence of different assessment conditions (e.g., in different lighting). The accuracy of assessments also increases, and it is achievable without the support of a specialized hand movement laboratory, even at the level of an ordinary clinic. Thus, a new automated model for assessing hand movements is being created, improving the efficiency of diagnosis, therapy and care (including, detection of swelling or its changes). Multiple testing of solutions is supported by the possibility of using new antibacterial polymers for 3D printing to prevent skin infections during rehabilitation but also exoskeleton testing [21]. To date, the purpose of such studies has mainly been to determine the functional and neuromuscular changes in the participant induced by the 3D-printed exoskeleton, and evaluation has primarily used clinimetric scores and scales (Fugl-Meyer Assessment and Box and Block Test) and tests the participant's forearm muscle strength and activation (EMG), possibly through patient satisfaction questionnaires [21]. In a study by [PERSON] et al. [61], 22 people were tested in three different exoskeleton conditions for each grip task, i.e., 90 repetitions in random order. The study shows that the effect of the exoskeleton varies depending on the gripping task and the gender of the participant, and significant individual differences were also observed [2]. An area of particular risk is children and those with sensory deficits. In a study by [PERSON] et al. [62], it was shown that in a group of children and adolescents, the Box and Block test, the Selective Upper Limb Control Scale and finger extensor muscle strength differentiated well participants who improved their scores after using the exoskeleton and those who did not [62]. All participants needed help wearing the exoskeleton module, andthe median donning times were 62-160 s (i.e., less than 3 min) with high user acceptance of the exoskeleton [62]. Problems were observed with the durability of the transmission system, electronics and exoskeleton attachment system [62]. In addition to testing, it is worth conducting an exploratory analysis of the effects of using the exoskeleton in order to monitor it from the point of view of safety and applicable regulations (e.g., Medical Devices Regulations--MDR, ISO13484 and ISO 27001) [61]. Before the wider introduction of exoskeletons, recommendations are needed on technical issues, how to wear and remove the exoskeletons and how to use them in therapy or as a device to assist the patient's daily functioning at home.