Summary

The ability to grasp and manipulate with the hands is essential to the development of activities of daily living (ADL) of humans and guarantee a full independent and functional life. A key part of this ability lies in the kinematic complexity of the hand, with 25 degrees of freedom. This complexity has raised numerous studies that try to analyze and reproduce their behavior with different orientations and simplifications. Recently there are several researchers who, for different purposes, have focused on the use of postural synergies to reduce the complexity of the problem, losing little information as possible.

Furthermore, assessment of the hand is fundamental in the analysis of disability and dependence of people, as shown by the different classifications used in this regard. However, the methods used on those assessments are still quite subjective (patient’s and / or clinician’s appreciations): apart from clinical tests, invasive in many cases, the only objective methods used are measuring force in a few types of grasps and the maximum ranges of mobility of some joints. This project arises from the hypothesis that in order to determine more objectively the real limitation of pathology and its evolution, the kinematic synergies used by pathological hands in performing ADL could be compared with those used by the healthy hand. This has not yet been done and can be a very valuable tool, together with patient history to objectively assess functionality.

Therefore, the main objective of the project is to characterise the kinematics of the human hand in grasping and manipulating objects under representative tasks of daily living, focused on the functional assessment of pathologies, which might be made explicit in:

1. Characterising the kinematics of the hand studying the synergies of the joints of the hand during the development of AVD. These synergies would be measured not only in terms of postural coordination patterns, but also of ranges and changing rates of those patterns.
2. Establishing a database of normality of these synergies for healthy subjects from the registration of a representative sample of tasks and objects in healthy subjects. Objects with designs adapted for grasping will also be used in order to check if the kinematic deficiencies detected in some patients can be solved with them.
3. Determining the most effective kinematic parameters from those used (patterns, ranges and rates) to assess the dysfunctionality of some pathology, in order to complement and / or improve current assessment techniques.