Assessing kinematic variability during performance of Jebsen-Taylor Hand Function Test.

Area of Science:

• Biomechanics
• Human movement analysis
• Clinical kinesiology

Background:

• 3D motion capture offers potential for augmenting upper limb disability evaluations.
• Understanding typical kinematic motion during functional tasks is crucial for interpreting patient performance.
• The Jebsen-Taylor Hand Function Test (JHFT) is a standard clinical assessment for hand function.

Purpose of the Study:

• To assess kinematic variability during the JHFT.
• To establish normative kinematic patterns for JHFT tasks.
• To provide a basis for identifying atypical movement in clinical populations.

Main Methods:

• Twenty-two subjects without upper limb disability performed the JHFT.
• Upper body joint kinematics were captured using a Vicon motion capture system.
• Intrasubject and intersubject variability were quantified using Pearson's correlation coefficient and adjusted coefficient of multiple correlation (CMCadj).

Main Results:

• Writing and picking up small objects tasks showed high intrasubject variability (median Pearson's r < 0.7).
• Can-lifting tasks demonstrated high consistency across subjects for elbow, shoulder, and torso joints (CMCadj > 0.5).
• Writing tasks exhibited low intersubject consistency across all joint angles (CMCadj < 0.07).

Conclusions:

• Kinematic patterns for JHFT tasks were successfully analyzed.
• Defined kinematic patterns can help identify and adjust atypical motion in patients.
• Results inform task selection for kinematic evaluations and provide expected variability for clinical and regulatory assessment.