Background & Aims

The management of entrapment neuropathies, like carpal tunnel syndrome (CTS), entails a challenge in the clinical setting. Current clinical guidelines recommend the use of a conservative approach, such as physiotherapy, before more invasive interventions are considered. Neurodynamic interventions are commonly used by physiotherapists to treat people with peripheral nerve involvement. While the efficacy of this intervention has been confirmed in a subgroup of people with CTS, the mechanisms of action of neurodynamic exercises are yet to be fully understood.

The MONET (mechanisms of neurodynamic treatment) study aims to investigate the mechanisms of action of a 6-week home-based progressive neurodynamic intervention on nerve structure and function.

Methods

This mechanistic, randomised, single-blind, controlled trial includes people with mild or moderate CTS and healthy participants. Participants undergo clinical, electrophysiological, and advance magnetic resonance neurography (MRN) assessment. Patients with CTS are randomly assigned to 1) a 6-week progressive home-based neurodynamic exercise intervention (n=26), 2) a steroid injection (=26), or 3) advice (n=26) group. All participants attend a 3T MRN session to visualise the median nerve at the wrist. The protocol includes the acquisition of multishell (b=0, b=300 and 800 s/mm2) diffusion-weighted imaging (DWI) scans, true fast imaging with steady-state free precession (TRUFI) with/without magnetisation transfer (MT) preparation, and T2-mapping. Fractional anisotropy of the median nerve, as our primary outcome measure, is obtained along with mean diffusivity and radial diffusivity from DWI, T2 from T2-mapping sequences, and magnetisation transfer ratio from TRUFI.

Results

While the MONET study is ongoing, we will present our baseline findings comparing nerve function and structure in people with CTS compared to healthy controls.

Conclusions

The utility of advanced MRN sequences to help understand changes in neural microstructure will be discussed. Ultimately, the findings of the MONET study are a first step towards precision therapy by helping to identify which patients are more likely to benefit from neurodynamic interventions.

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Presenting Author

Eva Sierra-Silvestre

Poster Authors

Eva Sierra Silvestre

PhD

Oxford University

Lead Author

Mohamed Tachrount

PhD

Lead Author

Andreas Themistocleous

University Of Oxford

Lead Author

Max Steward

MSc

Lead Author

Georgios Baskozos

PhD

Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom

Lead Author

Annina Schmid

PhD

Lead Author

Topics

  • Treatment/Management: Interventional Therapies – Other