Defining the role of sensation, strength, and prehension for upper limb function in cervical spinal cord injury.
BACKGROUND
Upper limb function plays a significant role in enhancing independence for individuals with tetraplegia. However, there is limited knowledge about the specific input of sensorimotor deficits on upper limb function. Thus the theoretical framework designed to develop the Graded Redefined Assessment of Strength Sensibility and Prehension (GRASSP) was used as a hypothetical model to analyze the impact of impairment on function.


OBJECTIVE
To define the association of impairment (sensation, strength, and prehension measured by the GRASSP) to upper limb function as defined by functional measures (Capabilities of Upper Extremity Questionnaire, Spinal Cord Independence Measure).


METHODS
A hypothetical model representing relationships by applying structural equation modeling was used to estimate the effect of the impairment domains in GRASSP on upper limb function. Data collected on 72 chronic individuals with tetraplegia was used to test the hypothetical model.


RESULTS
Structural equation modeling confirmed strong associations between sensation, strength, and prehension with upper limb function, and determined 72% of the variance in "sensorimotor upper limb function" was explained by the model. Statistics of fit showed the data did fit the hypothesized model. Sensation and strength influence upper limb function directly and indirectly with prehension as the mediator.


CONCLUSIONS
The GRASSP is a sensitive diagnostic tool in distinguishing the relative contribution of strength, sensation and prehension to function. Thus, the impact of interventions on specific domains of impairment and related contribution on clinical recovery of the upper limb can be detailed to optimize rehabilitation programs.
['Kalsi-Ryan|Sukhvinder|S|', 'Beaton|Dorcas|D|', 'Curt|Armin|A|', 'Duff|Susan|S|', 'Jiang|Depeng|D|', 'Popovic|Milos R|MR|', 'Rudhe|Claudia|C|', 'Fehlings|Michael G|MG|', 'Verrier|Mary C|MC|']
D002574:Cervical Vertebrae D003430:Cross-Sectional Studies D004185:Disability Evaluation D018737:Hand Strength D006801:Humans D008962:Models, Theoretical D053580:Muscle Strength D011782:Quadriplegia D012677:Sensation D013119:Spinal Cord Injuries D034941:Upper Extremity
upper limb function tetraplegia impairment hand