Early sensory relearning after median nerve repair using mirror training and sense substitution

Abstract

Background.

The design and protocol of sensory re-education programmes has not changed over the last decades – a fact that may appear surprising when considering the enormous advances in neuroscience, cognitive science and brain imaging techniques that have increased our understanding of brain plasticity. A multitude of intrinsic and extrinsic factors influence the functional outcome after a nerve repair. Timing of when the sensory relearning is begun is one of them.

Methods.

Here we present a case following median nerve repair, where sensory re-education was introduced in the second week following surgery, i.e. long before any signs of nerve regeneration in the hand and fingers (Phase 1 sensory relearning). The aim was to activate and maintain the cortical hand representation areas for median nerve innervated parts of the hand. Mirror training and a new method with auditory input that substitute temporary missing sensory input were used. For evaluation, the Model Instrument for Outcome after Nerve Repair was utilized.

Results.

There was an improvement in overall score especially in the sensory domain of the Model Instrument for Outcome after Nerve Repair over the 25 months and this exceeded the upper limit of the 95% reference interval for an adult population.

Conclusions.

The excellent outcome in this case adds to other studies indicating that very early introduction of sensory relearning can greatly enhance the outcome following nerve repair.