Variation in amyotrophic lateral sclerosis presentation and outcomes based on phenotype and physical therapy movement system diagnosis: a case series

Background: Amyotrophic Lateral Sclerosis (ALS) is a progressive motor neuron disease and presentation varies. There is limited description of this variability and how physical therapy (PT) specific movement system diagnoses (MSD) may impact care.

Purpose: The purpose of this case series is to describe the variability of ALS presentation longitudinally across early, middle, and late stages of ALS based on phenotype and MSD.

Methods: Four individuals were selected from an ALS clinic chart review representing a unique combination of phenotypes and MSDs (Case 1: bulbar onset force production deficit (FPD), Case 2: bulbar onset fractionated movement deficit (FMD), Case 3: limb onset FPD, Case 4: limb onset FMD). Descriptions of care over 9 years included outcomes of disability (ALS Functional Rating scale-revised), activity (10 Meter Walk Test, Five Times Sit to Stand Test, Trunk Impairment Scale-version 2), and impairment (strength and spasticity).

Results: Persons with ALS were seen every 3 to 6 months (10 to 19 visits total). Determination of MSD was hardest to complete in early stage bulbar onset ALS. Patterns of decline through stages varied by MSD and phenotype, most notably in length of time in middle stage. Limb onset FMD had the slowest progression. Falls and fall related injuries were most frequent in limb onset ALS but falls occurred in all cases.

Conclusion: The combination of MSD and phenotype enhanced variability description offers new insights into clinical decision-making in ALS care.