The assessment of grip strength in preschool-aged children with and without unilateral cerebral palsy

To investigate reliability and validity of two grip strength devices in children with and without unilateral cerebral palsy (uCP) aged 2–6 years.
We assessed grip strength in 20 pre-school-aged children with predominantly spastic uCP (mean age 4y0 ± 1y2m) and 20 age-matched children without uCP (mean age 3y11m ± 1y3m) using the Martin Vigorimeter and MyoGrip to investigate test-retest reliability (intraclass correlation coefficients; ICC), known-group validity (comparative statistics) and convergent validity (correlation analyses) in a cross-sectional design.
In both groups, test-retest reliability was excellent for both devices and both hands (ICC 0.91–0.97). Grip strength of the non-preferred hand was lower in children with uCP for both devices (p < 0.001). Grip strength was decreased in the non-preferred compared to the preferred hand in children with uCP for both devices (p < 0.001). In children without uCP, grip strength was lower in the non-preferred compared to the preferred hand only for the MyoGrip (p = 0.02). The relation between both devices for both hands was good to very high (r = 0.62–0.92, p < 0.007).
Both devices can be implemented in clinical practice to assess grip strength in preschool-aged children with uCP. Only the MyoGrip detected differences between both hands in children without uCP and might be more sensitive.

The Vigorimeter and MyoGrip reliably and validly assess grip strength in preschoolers with and without unilateral cerebral palsy
Both tools allow accurate grip strength assessment supporting diagnosis and intervention planning
For unilateral cerebral palsy, the Myogrip seems more sensitive in detecting differences than the Vigorimeter

The Vigorimeter and MyoGrip reliably and validly assess grip strength in preschoolers with and without unilateral cerebral palsy
Both tools allow accurate grip strength assessment supporting diagnosis and intervention planning
For unilateral cerebral palsy, the Myogrip seems more sensitive in detecting differences than the Vigorimeter