The Aim of the Study is to Characterize Patients Exhibiting Muscular Atrophy and Weakness Who Require a Muscle Biopsy for Diagnosis (IBM vs Atypical MND), Through an Innovative Technique Which Enables the Evaluation of the Neuromuscular Junction Involvement in Each Condition

Comparative Analysis of TDP-43 Pathology in Skeletal Muscle Biopsies With Electrostimulation for Enhanced Neuromuscular Junction Sampling in Patients Affected by Inclusion Body Myopathy (IBM) and Motor Neuron Disease (MND)

The aim of the study is to characterize 30 patients exhibiting muscular atrophy and weakness who require a muscle biopsy for diagnosis (suspected inclusion body myopathy vs atypical motor neuron disease), through an innovative technique (a muscle biopsy with Electrostimulation for Enhanced Neuromuscular Junction sampling), to evaluate the involvement of the neuromuscular junction in each disease and to better characterize shared and divergent patterns of TDP-43 pathology within the peripheral nervous system in both disorders.

Inclusion Criteria:

• Patients exhibiting progressive muscle weakness and atrophy with a classic clinical IBM pattern or with an atypical clinical IBM pattern or with an atypical MND pattern
• Able to understand and sign the informed consent
• Treated according to standard of care clinical practice

Exclusion Criteria:

• Contraindications to needle EMG or skeletal muscle biopsy
• Psychiatric diseases that may interfere with adherence to the follow-up protocol