Abstract

Introduction

Limb amputations drastically affect an individual’s quality of life, making advanced prosthetic technologies essential to prevent life-long disability. While robotics have progressed significantly, achieving seamless, intuitive control and natural sensory feedback with artificial limbs remains a major challenge. Both intuitive motor control and sensory feedback are vital for functional prostheses. Techniques such as Targeted Muscle Reinnervation (TMR) [1] and Targeted Sensory Reinnervation (TSR) [2] have shown the benefits of reinnervating muscles and skin to replicate natural limb functions. Newer approaches, including Regenerative Peripheral Nerve Interfaces (RPNIs), Vascularized Denervated Muscle Targets (VDMTs), and Cutaneous Mechanoneural Interfaces (CMIs), hold potential but face hurdles in clinical adoption due to their dependence on implanted electrodes [3]. A variety of implantable systems have been researched but are not yet clinically available [4]. Osseointegration for skeletal attachment has proven to be an effective means of anchoring a prosthetic limb to the body [5], and more recently, this technology has been employed to solve the bidirectional communication challenge between implanted electrodes and prosthesis [6].

Mots Clés

Prosthetic limbs, osseointegration, neural interfaces, surgical reconstruction, sensory feedback, postamputation pain, phantom limb pain.

Corps du résumé / Matériels et méthodes

Using direct skeletal attachment via osseointegration, neuromuscular interfaces, and machine learning, we achieved the first clinical implementation of an artificial arm integrated directly into the patient’s bone, nerves, and muscles [7]. In addition to direct skeletal attachment, this technology provides the unique opportunity to chronically record and stimulate the neuromuscular system in freely behaving humans, thus permitting investigate complex limb motions and somatosensory perception. The first patient implanted with this neuromusculoskeletal interface has used it without interruption for over 10 years in everyday life. Patients implanted with this system are also provided with intuitive sensory feedback via direct nerve stimulation [6]. Direct skeletal attachment via osseointegration, along with control and sensory feedback via implanted neuromuscular electrodes, can now be provided in a self-contained prosthesis for use in daily life without supervision outside controlled environments. Originally developed for above-elbow amputations, this technology has also been implemented in below-elbow amputations [8], and more recently, used with refined surgical reconstruction presenting the first concurrent implementation of TMR and RPNIs [9].

Résultats

In addition to the functional challenges that limb loss represents, these patients often develop chronic neuropathic pain that further hinders their quality of life. Research and clinical innovations on the treatment of post-amputation pain have increased in the past decade. A growing interest on post-amputation pain, particularly in phantom limb pain (PLP), has resulted in new treatments, basic research findings, and theories that have increased our understanding of this condition [10].

Discussion

In this lecture, I will provide an overview of the field and discuss his recent hypothesis for the neurogenesis of PLP, along with a novel theoretical framework for further understanding the condition and improving its treatment [11]. I will also discuss how motor decoding technology in combination with virtual reality has been used to treat PLP [12]. He will also describe how such technologies have been used for the functional and pain rehabilitation of sever sensorimotor impairments.

Conclusion

The Russian full-scale invasion of Ukraine has left over 100,000 people with amputations and a high incidence of PLP. I will also present the challenges of rehabilitation in the time of war after one year experience of full-time humanitarian work.

Bibliographie / Références

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