ALS-OPM

In ALS, heterogeneity of motor phenotypes is a fundamental hallmark of the disease. Motor phenotyping is an essential aspect of assessing the clinical heterogeneity of ALS. It is determined by the variability of three anatomical determinants: the region of onset, the propagation of motor symptoms from the region of onset to another vertically located body region, and the degree of upper motor neuron (UMN) and lower motor neuron (LMN) dysfunction (reference).

Developed through expert consensus from Germany, Austria and Switzerland, this classification aims to standardize the description of ALS motor phenotypes, enhance prognostic precision, and improve patient stratification in clinical trials. A revised version of ALS-OPM (ALS-OPM 3.3) is now available for download. The revised ALS-OPM 3.3 reflects further consensus work from the ALS Motor Phenotype Symposium held in Berlin in September 2025 and was published in ALS-FTD on 17 March 2026 (reference).

The ALS-OPM materials, including guidance, glossary, and an overview of motor neuron symptoms and signs, available here support standardized documentation of phenotypes in clinical care and research. An interactive version for direct digital data capture and print use is available for clinical and research settings.

The ALS Functional Rating Scale-Revised version (ALSFRS-R) is a disease-specific severity score that reflects motor impairment and functional deterioration in people with ALS. The ALSFRS-R-SE (self-explanatory) is an adapted version of the widely used ALS Functional Rating Scale-Revised (ALSFRS-R). It retains the original scale’s structure while incorporating clear annotations and explanatory notes to make the tool more self-explanatory for clinicians, patients, and caregivers alike. Developed through a rigorous consensus process in Germany, the ALSFRS-R-SE improves the consistency and validity of functional assessments by addressing linguistic ambiguities and standardizing item interpretation (reference). This enhances its use in both clinical care and research, supporting accurate monitoring of disease progression and outcome measurement.

A new ALSFRS-R-SE version 2.1 is now available for download. In the new version, the self-explanatory sections have been further optimized. An interactive version for direct digital data capture and print use is available for clinical and research settings.