Characterization of kinematic synergies of the hand in activities of daily living oriented to functional evaluation
Abstract:
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 characterize 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) Characterizing 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.
