Grip strength dynamometry: Reliability and validity for adults with upper limb burns

BackgroundUpper limb (UL) burns can result in significant loss of strength and physical function. The aim of this study was to establish the reliability and validity of grip strength dynamometry (GSD) for measuring burn-affected UL strength over time.MethodsA retrospective sample of adult participants (n = 89) with UL burns was obtained from Royal Perth Hospital. Data were compiled from assessments conducted at discharge, one, three, six and 12 months afer burn. Within-session reliability and validity was examined through multivariable analyses.ResultsGSD demonstrated within-session reliability for all investigated timepoints (ICC's ≥ 0.87, p < 0.0005.) Criterion validity was confirmed with GSD and QuickDASH being significantly associated in both right (b = 0.17, p = 0.002) and left (b = 0.14, p = 0.002) hands. Construct validity was demonstrated through significant association of GSD values with location of burn (p < 0.35); time after burn (p < 0.012); surgical intervention (p = 0.003) and burn size (p < 0.05).ConclusionThis study demonstrates that grip strength dynamometry is a reliable and valid outcome measure for measuring burn-affected UL strength from one month to one year after burn.