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Published on: February 12, 2018
Quantitative Motion Measurements Based on Markerless 3D Full-Body Tracking in Children with SMA Highly Correlate with
Astrid Blaschek1, Nikolas Hesse2, Birgit Warken1
1Ludwig Maximilian University of Munich (LMU), Hauner Children's Hospital, Paediatric Neurology and Developmental Medicine, Munich, Germany.
Insights
A new motion tracking system, KineMAT, objectively measures motor function in children with Spinal Muscular Atrophy (SMA). This technology offers a reliable alternative to subjective clinical evaluations for assessing disease progression and treatment efficacy.
Area of Science:
- Biomedical Engineering
- Neurology
- Pediatrics
Background:
- Spinal Muscular Atrophy (SMA) is a leading cause of childhood neurodegenerative disease.
- Emerging therapies aim to mitigate rapid motor decline in SMA patients.
- Current assessments like the Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND) are subjective and require extensive training.
Purpose of the Study:
- To demonstrate the feasibility of a novel motion tracking method for capturing intricate movement patterns in children with SMA.
- To validate a new system for objective motor function assessment in pediatric SMA patients.
Main Methods:
- Developed KineMAT, a markerless motion tracking system using an RGB-depth sensor.
- Recorded 10 SMA patients (2-46 months; CHOP INTEND 10-50) for 2 minutes of spontaneous activity.
- Correlated 56 degrees of freedom of joint motion with CHOP INTEND scores using Pearson correlation.
Main Results:
- Four key motion parameters strongly correlated with CHOP INTEND scores (r > 0.92).
- Parameters included standard deviation of joint angles and positions, and absolute travel distance of extremities.
- High test-retest reliability (1.3-10.5%) was observed for the motion parameters.
Conclusions:
- Markerless whole-body motion capture with KineMAT objectively assesses motor performance in SMA.
- This technology provides reliable, quantitative data across varying SMA severity and age groups.
- KineMAT offers a promising tool for evaluating therapeutic interventions in Spinal Muscular Atrophy.
Background:
Spinal Muscular Atrophy (SMA) is the most common neurodegenerative disease in childhood. New therapeutic interventions have been developed to interrupt rapid motor deterioration. The current standard of clinical evaluation for severely weak infants is the Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND), originally developed for SMA type 1. This test however, remains subjective and requires extensive training to be performed reliably.
Objective:
Proof of principle of the motion tracking method for capturing complex movement patterns in ten children with SMA.
Methods:
We have developed a system for tracking full-body motion in infants (KineMAT) using a commercially available, low-cost RGB-depth sensor. Ten patients with SMA (2-46 months of age; CHOP INTEND score 10-50) were recorded for 2 minutes during unperturbed spontaneous whole-body activity. Five predefined motion parameters representing 56 degrees of freedom of upper, lower extremities and trunk joints were correlated with CHOP INTEND scores using Pearson product momentum correlation (r). Test-retest analysis in two patients used descriptive statistics.
Results:
4/5 preselected motion parameters highly correlated with CHOP INTEND: 1. Standard deviation of joint angles (r = 0.959, test-retest range 1.3-1.9%), 2. Standard deviation of joint position (r = 0.933, test-retest range 2.9%), 3. Absolute distance of hand/foot travelled (r = 0.937, test-retest range 6-10.5%), 4. Absolute distance of hand/foot travelled against gravity (r = 0.923; test-retest range 4.8-8.5%).
Conclusions:
Markerless whole-body motion capture using the KineMAT proved to objectively capture motor performance in infants and children with SMA across different severity and ages.
