Intraoperative Quantification of MDS-UPDRS Tremor Measurements Using 3D Accelerometry: A Pilot Study

Area of Science:

• Neurology
• Biomedical Engineering
• Movement Disorders

Background:

• The Movement Disorder Society—Unified PD Rating Scale (MDS-UPDRS) is standard for Parkinson's disease (PD) tremor assessment.
• MDS-UPDRS suffers from subjectivity and rater dependency.
• Objective motor measurements via accelerometry offer a potential solution.

Purpose of the Study:

• To translate MDS-UPDRS tremor tests into an objective scoring method using 3D accelerometry.
• To develop and validate an algorithm for measuring and classifying PD tremor based on MDS-UPDRS criteria.

Main Methods:

• 28 PD patients and 26 healthy controls underwent MDS-UPDRS tremor rating and 3D accelerometry of index fingers.
• Measurements were taken in an off-medication state.
• Quantitative metrics like tremor amplitude and power spectral density were calculated.

Main Results:

• A substantial concordance (>69.6%) was found between accelerometric and MDS-UPDRS tremor scores.
• Trends aligned with previous studies on tremor amplitude and MDS-UPDRS scores.
• Accelerometric kinetic tremor measures showed poor association (R2 < 0.3) with MDS-UPDRS, attributed to noise in healthy controls.

Conclusions:

• MDS-UPDRS tremor tests can be objectively translated using accelerometry.
• Discrepancies exist between objective kinetic tremor measures and subjective MDS-UPDRS ratings.
• This technology promises reduced rater dependency and objective intraoperative tremor monitoring.