Commentary on “Handgrip Strength: A Population-Based Study of Norms and Age Trajectories for 3- to 17-Year-Olds”
Adequate grip strength is important for having the ability to perform activities of daily living such as dressing, feeding, and grooming. Having a comprehensive tool that identifies normative values for grip strength based on age and hand dominance can be helpful for clinicians when establishing a physical baseline and identifying decreased function. Tracking strength and functional improvements over time assist therapists in determining the frequency and duration of therapy needed, as well as setting short-/long-term goals. Children younger than 9 years have little strength difference between hands and therefore, if a difference is identified during assessment, treatment should be focused on strengthening the weaker hand. Intervention needs to be individualized to each patient, keeping in mind that grip strength differences between boys and girls become more apparent around 10 years of age. Having values that span ages as young as 3 to 17 years of age can be helpful when evaluating dysfunction and identifying the need for adaptive tools/equipment.
Parent response: My child has Charcot-Marie-Tooth disease and benefits from specialized therapy that addresses his hand weakness. This article made me realize that I should be focusing on my child's weaker hand at a younger age so that as he grows and develops, his strength can become comparable to the norms. Having grip strength norms gives me a baseline to compare my child to and show his strength and weaknesses and what he needs to work on.
“What should I be mindful about when applying this information?”
Although there are other studies with normative data, this study was conducted using a random and large sample size of individuals as young as 3 years of age. The majority of the sample was from Caucasian adolescents in the United States, and the results may not necessarily apply to all ethnicities and populations. Three-year-olds are not always consistent with following directions, which could decrease the reliability of testing and results. Even so, therapists should consider using this tool because of its age span and separation of dominant and nondominant hands. It may be appropriate to share normative values with patients and parents so that they can compare their strength to children developing typically and adolescents. These shared results can help both child and parent become more invested in therapy as well as with their home exercise program. Every diagnosis is different and must be used with caution when determining course of therapy treatment. It was noted that after 13 years of age, boys began to have greater grip strength compared with girls. Although it is hypothesized that this is due to puberty, further studies need to be completed to determine this causality.
Parent response: As my child gets older, he requires therapies that are specialized to his needs and having norms like this will help the therapist provide proper treatment for him. The results are on adolescents developing typically and it would be good to have values for different diagnoses.