Peripheral nerve injuries, pain, and neuroplasticity

Abstract

Introduction: Peripheral nerve injuries (PNIs) cause both structural and functional brain changes that may be associated with significant sensorimotor abnormalities and pain.

Purpose of the study: The aim of this narrative review is to provide hand therapists an overview of PNI-induced neuroplasticity and to explain how the brain changes following PNI, repair, and during rehabilitation.

Methods: Toward this goal, we review key aspects of neuroplasticity and neuroimaging and discuss sensory testing techniques used to study neuroplasticity in PNI patients.

Results: We describe the specific brain changes that occur during the repair and recovery process of both traumatic (eg, transection) and nontraumatic (eg, compression) nerve injuries. We also explain how these changes contribute to common symptoms including hypoesthesia, hyperalgesia, cold sensitivity, and chronic neurogenic pain. In addition, we describe how maladaptive neuroplasticity as well as psychological and personality characteristics impacts treatment outcome.

Discussion and conclusion: Greater understanding of the brain's contribution to symptoms in recovering PNI patients could help guide rehabilitation strategies and inform the development of novel techniques to counteract these maladaptive brain changes and ultimately improve outcomes.

Keywords: Neuropathic pain; Neuroplasticity; Peripheral nerve injury; Rehabilitation.