Prediction of the range of hand positions available to a patient with movement restrictions at the joints of the upper limb--a mathematical model

Area of Science:

• Biomechanics
• Rehabilitation Engineering
• Medical Modeling

Background:

• Patients with reduced range of motion in upper limb joints often face challenges in daily activities.
• Accurate prediction of available workspace is crucial for effective rehabilitation planning.
• Existing models may not fully capture the complexities of upper limb kinematics.

Purpose of the Study:

• To develop and validate a mathematical model for predicting upper limb workspace in individuals with joint motion limitations.
• To compare model predictions with experimental data and identify sources of discrepancy.
• To explore the potential of the model for assisting in the planning of upper limb rehabilitation.

Main Methods:

• Utilized the inverse kinematic method based on Benati et al. (1982).
• Incorporated simplified anatomical data for upper limb joint modeling.
• Compared model-generated workspace data with experimental data from Dempster (1955).

Main Results:

• The mathematical model successfully predicted significant differences in upper limb workspace between normal individuals and those with joint restrictions.
• Discrepancies between model predictions and experimental data were observed, attributed to scapular constraint and anatomical modeling simplifications.
• The model shows potential for future improvements with enhanced anatomical data.

Conclusions:

• The developed mathematical model demonstrates the capability to differentiate workspaces based on joint mobility limitations.
• The model, when refined with empirical data, can serve as a foundation for an expert system to guide upper limb rehabilitation.
• Further refinement of anatomical modeling is recommended to improve prediction accuracy.