Early and consistent pattern of proximal weakness in GNE myopathy

Area of Science:

• Neurology
• Genetics
• Myology

Background:

• GNE myopathy is typically characterized as a distal myopathy.
• Proximal muscle involvement in GNE myopathy has not been systematically investigated.

Purpose of the Study:

• To systematically analyze the phenotype of genetically confirmed GNE myopathy patients.
• To evaluate the extent and pattern of proximal and distal muscle involvement.

Main Methods:

• Phenotypic analysis of genetically confirmed GNE myopathy patients.
• Muscle strength assessment using Medical Research Council (MRC) grading.
• Calculation of Average Muscle Scores (AMS) for 14 muscle groups.

Main Results:

• Severe weakness observed in hip adductors, hip flexors, knee flexors, and foot dorsiflexors.
• Milder weakness in hip extensors and abductors; knee extensors largely unaffected.
• Proximal muscle weakness was an early feature, present in all evaluated patients.

Conclusions:

• The GNE myopathy phenotype in this Indian cohort presents with mixed proximal and distal muscle involvement.
• Hip adductor and flexor weakness are key components of the GNE myopathy phenotype.