Features Suggestive of Coexisting Amyotrophic Lateral Sclerosis in Patients With Spinal Stenosis and Influence of Spinal Decompression.

Background:  Spinal stenosis and amyotrophic lateral sclerosis (ALS) can co-occur and both manifest as signs of dysfunction of lower and/or upper motor neurons. Few studies have identified factors that alert the diagnosis of ALS in patients with spinal stenosis, and the influence of spinal decompression surgery on ALS progression remains unclear.

Objective: The objective of this study is to describe factors that are suggestive of an ALS diagnosis in patients with spinal stenosis and influence of spinal decompression surgery on the progression of ALS  Materials and methods: A retrospective review of the institutional ALS database and electronic medical records was performed to identify patients with coexisting diagnoses of ALS and moderate to severe cervical and/or lumbosacral spine stenosis. Identified patients were divided into two subgroups: those with spinal decompression surgery and those without. Comparisons of clinical features and progression of ALS were made between subgroups.

Results:  A total of 77 patients with ALS and coexisting moderate to severe cervical or lumbosacral spine stenosis were included. Among them, 50 patients underwent spinal decompression surgery and 27 did not. In comparison to patients with spinal decompression, patients without spinal decompression surgery were seen more frequently by neurologists (74% versus 26%), had less prominent radicular pain (19% versus 50%), demonstrated more frequent bulbar signs (30% versus 8%), experienced more likely weight loss (41% versus 4%), and disclosed more noticeable axonal loss changes on electromyography. Spinal decompression surgery did not modify the progression of ALS based on ALSFRS-R score change and analysis of survival duration.

Conclusion: Our study identified a number of useful features that are suggestive of an ALS diagnosis when evaluating patients with spinal stenosis and may support the performance of spinal decompression surgery in a subset of selected ALS patients with symptomatic spinal stenosis.