Digitised spirography as an evaluation tool for intention tremor in multiple sclerosis.

Area of Science:

• Neurology
• Biomedical Engineering
• Rehabilitation Science

Background:

• Intention tremor is a common and disabling symptom in multiple sclerosis (MS).
• Objective quantification of tremor severity and related disability is crucial for effective management.
• Current assessment methods may lack precision or objectivity.

Purpose of the Study:

• To investigate the validity and reliability of digitised circle and square spiral drawing (spirography) for quantifying intention tremor in MS patients.
• To compare spirography measurements with clinical assessments of tremor severity and arm functionality.
• To evaluate the test-retest reliability of the digitised spirography method.

Main Methods:

• Digitised circle and square spiral drawings were performed by MS patients with tremor, MS patients without tremor, and healthy controls.
• Tremor amplitude was measured using the standard deviation of drawing velocity in specific directions.
• Spirographic variables were correlated with clinical scales (Fahn's Tremor Rating Scale, TEMPA, nine-hole-peg test) and compared between groups.

Main Results:

• Digitised spirography variables successfully differentiated between MS patients with tremor and those without, as well as healthy controls.
• High correlation coefficients between spirography variables and clinical ratings demonstrated good validity.
• Consistent results across four repeated trials indicated good short-term test-retest reliability.

Conclusions:

• Digitised spirography is a valid and reliable method for quantifying intention tremor severity in multiple sclerosis.
• This technique provides objective data that correlates well with clinical assessments of tremor and arm disability.
• Digitised spirography represents a useful instrumentation for the objective assessment of MS intention tremor.