A novel method for the quantification of key components of manual dexterity after stroke

Abstract

BackgroundA high degree of manual dexterity is a central feature of the human upper limb. A rich interplay of sensory and motor components in the hand and fingers allows for independent control of fingers in terms of timing, kinematics and force. Stroke often leads to impaired hand function and decreased manual dexterity, limiting activities of daily living and impacting quality of life. Clinically, there is a lack of quantitative multi-dimensional measures of manual dexterity. We therefore developed the Finger Force Manipulandum (FFM), which allows quantification of key components of manual dexterity. The purpose of this study was (i) to test the feasibility of using the FFM to measure key components of manual dexterity in hemiparetic stroke patients, (ii) to compare differences in dexterity components between stroke patients and controls, and (iii) to describe individual profiles of dexterity components in stroke patients.Methods10 stroke patients with mild-to-moderate hemiparesis and 10 healthy subjects were recruited. Clinical measures of hand function included the Action Research Arm Test and the Moberg Pick-Up Test. Four FFM tasks were used: (1) Finger Force Tracking to measure force control, (2) Sequential Finger Tapping to measure the ability to perform motor sequences, (3) Single Finger Tapping to measure timing effects, and (4) Multi-Finger Tapping to measure the ability to selectively move fingers in specified combinations (independence of finger movements).ResultsMost stroke patients could perform the tracking task, as well as the single and multi-finger tapping tasks. However, only four patients performed the sequence task. Patients showed less accurate force control, reduced tapping rate, and reduced independence of finger movements compared to controls. Unwanted (erroneous) finger taps and overflow to non-tapping fingers were increased in patients. Dexterity components were not systematically related among each other, resulting in individually different profiles of deficient dexterity. Some of the FFM measures correlated with clinical scores.ConclusionsQuantifying some of the key components of manual dexterity with the FFM is feasible in moderately affected hemiparetic patients. The FFM can detect group differences and individual profiles of deficient dexterity. The FFM is a promising tool for the measurement of key components of manual dexterity after stroke and could allow improved targeting of motor rehabilitation.

Perceived ability to perform daily hand activities after stroke and associated factors: a cross-sectional study

“…Manual dexterity includes the ability to execute coordinated hand and finger movements when grasping, manipulating and releasing objects. Reduced dexterity can result in impaired grip formation and independent finger movements, and in reduced timing and force regulation of the hand [38, 39]. As manual dexterity is important for upper extremity functioning it should be thoroughly assessed and intensively practiced during stroke rehabilitation to enhance the use of the hands in daily activities.…”

Improvement in arm and hand function after a stroke with task-oriented training

“…Independence in activity of daily living is closely related to proficiency in dexterity skills, which refers to the ability to grasp and manipulate objects, by accurate and coordinated hand and finger movements 3. Although strongly correlated, hand and finger control is often more impaired and harder to rehabilitate than proximal upper extremity control after a stroke 4 5.…”

Test−Retest Reliability and Convergent Validity of Three Manual Dexterity Measures in Persons With Chronic Stroke

“…Manual dexterity is the ability to perform coordinated hand and finger movements when grasping, manipulating, and releasing objects [1]. Tasks of manual dexterity require integrations of various sensorimotor functions such as grip formation, independent finger movements, timing, and force production [1]. Manual dexterity can be divided into gross and fine manual dexterity.…”