Introduction: Upper limb amputations account for 3% of the amputee population and cause impairment of both motor and sensory functions. In addition to restoring function, it is also important to restore somatosensory information. Recovery is performed by invasive-surgical insertion of interfaces directly into a specific nerve compartment for stimulation or non-invasive somatosensory feedback - vibrotactile, mechanotactile, electrotactile and temperature feedback applied on skin of the stump. Purpose: The purpose of this study is to review the scientific literature and analyse somatosensory feedback in upper limb prostheses, what it is, how it works, describing the characteristics of the systems and further defining the impact, advantages, disadvantages and advances of upper limb prostheses with somatosensory feedback. Methods: A review of the peer-reviewed and scientific literature in English and Slovenian language was performed in PubMed, Google Scholar, Science Direct and DiKUL. A single search was used – (upper limb OR upper extremity) AND (prosthetics OR prosthesis OR prostheses OR prostheses OR artificial) AND (somatosensory feedback OR sensory feedback). Results: Reviewing 16 articles, the measurements were mostly quantitative, when seven studies used qualitative research method. Generally, involving varying numbers of subjects from one to 32, who were healthy individuals without amputation or with amputation on different levels of upper limb. The duration of the studies varied from a few hours to a maximum of six months. Non-invasive (10) somatosensory feedback was included more often than invasive (6), and electrotactile (5) non-invasive somatosensory feedback was the most frequently studied. Discussion and conclusion: The hand is an important human tool for object manipulation and communication. With amputation, natural motor and sensory functions are replaced by specific ranges of motion and the choice of prosthesis components. This is why the restoration of somatosensory information is so important. It contributes to better motor control of the prosthesis, to a more natural movement of the upper limb. Additionally, it allows a sense of embodiment of the prosthesis, restores a more natural perception of sensations and can reduce the phantom pain. However, it does not necessarily have a positive effect on the aesthetics of the prosthesis and may add weight and complexity to the design of the upper limb prosthesis. Nevertheless, it increases overall confidence of prosthetic user, although there is still room for improvement.
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