Grip strength parameters and functional activities in young adults with unilateral cerebral palsy compared with healthy subjects
Objective: To determine reliability of maximal grip strength, muscle coordination and muscle endurance. To compare these parameters in young adults with unilateral cerebral palsy and healthy subjects. To evaluate the correlation of these variables with functional activities. Subjects: Twenty-six healthy subjects and 26 young adults with unilateral cerebral palsy recruited from a cohort study in young adults with cerebral palsy. Methods: Maximal grip strength, muscle coordination and muscle endurance were measured in both hands of all subjects. In the healthy subjects test-retest reliability was established. In the young adults with cerebral palsy, the Melbourne assessment and Abilhand Questionnaire were used to determine functional activities. Results: For the dominant and non-dominant hand the intraclass correlation coefficients for the maximal grip strength were 0.93 and 0.91, for the muscle coordination 0.81 and 0.86, and for the muscle endurance 0.59 for both sides. Maximal grip strength of the involved hand of patients was reduced compared with the uninvolved hand and compared with healthy subjects. There was no difference in muscle coordination and muscle endurance between the involved and uninvolved hands. These parameters, however, were significantly reduced in both hands compared with healthy subjects. Correlations between grip strength parameters and activity limitations were relatively weak and non-linear. Conclusion: Performance of activity is not directly related to grip strength parameters. The uninvolved hand of young adults with unilateral cerebral palsy also has impaired function.