Unbiased Quantification of Persistent Postural and Motor Deficits Following Spinal Cord Injury in Mice

Area of Science:

• Neuroscience
• Biomedical Engineering
• Rehabilitation Science

Background:

• Spinal cord injury (SCI) leads to complex motor and postural impairments.
• Conventional assessment methods like the Basso mouse scale (BMS) lack quantitative precision for subtle deficits.

Purpose of the Study:

• To develop and validate an unbiased, quantitative method for evaluating motor function and posture after SCI.
• To identify subtle, enduring functional deficits missed by traditional behavioral tests.

Main Methods:

• Utilized high-speed video tracking with machine learning for whole-body pose estimation (Blackbox system).
• Performed quantitative weight-bearing analyses and behavioral motif analysis (Keypoint MoSeq).
• Developed a web-based application for kinematic data visualization and analysis.

Main Results:

• Identified persistent SCI-induced postural deficits (e.g., altered paw spacing, femur width) beyond 42 days post-injury.
• Quantified sustained locomotor deficits including reduced travel distance and disrupted speed ratios.
• Observed changes in motor 'syllables' correlating with movement dynamics, while sensory deficits resolved by 21 days post-injury.

Conclusions:

• The Blackbox system provides accurate, quantitative assessment of SCI-induced motor and postural deficits.
• This advanced methodology reveals subtle functional impairments and aids in evaluating SCI therapeutic strategies.
• Quantitative kinematic analysis offers a more sensitive approach to understanding SCI recovery trajectories.