- Primary lateral sclerosis (PLS) is a rare disease. It leads to weakness in the muscle of
the arms, legs, and face. People with PLS develop muscle stiffness called spasticity.
Researchers want to find a better way to measure this. They want to see if ultrasound, which
uses sound waves to look at parts of the body, can measure spasticity and stiffness in
- To see if ultrasound can detect and measure muscle spasticity in people with PLS.
- People ages 18 75 who have a diagnosis of PLS and are enrolled in protocol 01-N-0145.
- Healthy volunteers ages 18 75.
- Participants with PLS will have 1 study visit. Healthy participants will have upto 5
visits. Each visit will be about 2 hours.
- Participants will have tests of muscle strength. They will be examined. They will push
their arms and legs against researchers in different positions.
- Participants will have tests of muscle stiffness. Their arms and legs will be moved
while they relax.
- Participants will have a muscle ultrasound test. They will lie on a table. Gel will be
placed on the skin over the muscles of the arms and legs. A probe, like a microphone,
will be moved over the skin. Researchers will look at several muscles.
- Participants should try to stay still during the ultrasound. It may be done several
times and may be done by different examiners.
Persons with corticospinal, or upper motor neuron dysfunction have increased muscle stiffness
from spasticity. Spasticity is established by clinical examination, but there are few
reliable objective measures of spasticity. New ultrasound techniques to measure the elastic
properties of tissue represent a potential measure of spasticity. The ultrasound measures of
tissue elasticity are painless and quick to perform, but their ability to detect changes
resulting from spasticity is uncertain. The goal of this pilot study is to see how much
ultrasound measures of muscle elasticity differ between patients with spasticity and healthy
controls. Secondary objectives are to correlate muscle elasticity measures with a clinical
rating scale of spasticity and to assess intra and inter-rater reliability. This is a
protocol for primary lateral sclerosis (PLS) patients who are enrolled in another NIH study
in which they have been diagnosed with spasticity.
23 adult PLS patients with arm or leg spasticity currently enrolled in an NIH protocol
30 healthy adult controls with normal neurological exams.
The first phase, an investigator training phase, is aimed to become familiar with the Siemens
Acuson S2000 after the upgrade. The two investigators will train with 5 healthy volunteers.
In the second phase inter-observer variability of the ultrasound and Ashworth scale will be
assessed by having healthy volunteers and patients evaluated by the different investigators.
Since spasticity does fluctuate throughout the day, subjects will be consecutively assessed
for inter-observer variability and within a few hours or around the same time the following
day (depending on patient availability) for intra-observer variability. Each investigator
will do the Ashworth scale independent of the other. Each investigator will do the ultrasound
independent of the other. In the third phase, we will assess patients and volunteers to reach
the sample size that a power analysis suggested that we would need to measure differences
between patients with spasticity and controls.
The primary outcome will be measuring muscle stiffness from the biceps brachii using
ultrasound elastography, which will be compared between patient groups and control groups. A
secondary outcome will be the correlation of muscle stiffness at rest with the modified
Ashworth score for elbow flexion. Measures of muscle strength and ultrasound measures of
density and thickness will be examined in an exploratory fashion. Elastography of the
tibialis anterior will be examined in an exploratory fashion.
- INCLUSION CRITERIA:<TAB>
- Adults between ages of 18-75; matched to the patient cohort
- No history of neurological disorder
- No use of medications that produce muscle relaxation within 1 week of study, such as
baclofen, cyclobenzaprine, or tizanidine.
- Able to give informed consent
- Adults between ages of 18-75
- A clinical diagnosis of primary lateral sclerosis determined in NIH protocol
- No contractures of arms and legs
- Able to give informed consent
- Mechanical limitation of elbow flexion
- Achilles tendon surgical procedures
- History of cervical radiculopathy
- History of botulinum injections