Background Juvenile idiopathic arthritis (JIA) is a chronic inflammatory disease resulting in joints arthritis and deformities in the hands and fingers. This leads to decrease of joint mobility and strength of the hands which can lead to physical and functional hand disability (1) and subsequent reduction in daily living activities (2). Despite the presence of indices to assess the hand function, grip strength assessment remains the strong predictor of both hand and upper limb function (3). Hand grip strength (HGS) can be measured quantitatively using a hand dynamometer (4). Although the role of HGS in evaluating hand function in JIA has been studied (5), the use of HGS as a predictor of disease activity and disability in JIA has not been explored.
Objectives The aim of the study was to evaluate the HGS in JIA patients using electronic hand dynamometer and to assess its relationship with JIA disease activity, disability and quality of life.
Methods Twenty-three patients with JIA (14 girls and 9 boys) diagnosed according to International League of Associations for Rheumatology (ILAR) classification criteria and 59 healthy children were enrolled in the study. The disease activity was assessed using Juvenile Disease Activity Score (JDAS-27). Juvenile Arthritis Functionality Scale (JAFS) and Pediatric QOL Inventory (PedsQL) were used to assess physical function and quality of life respectively. HGS was tested 3 times in each hand of every patient and control using electronic hand dynamometer and the mean value was considered.
Results Patients with JIA showed low HGS in one or both hands compared with healthy children (p=0.001). Grip strength showed a significant inverse correlation with JDAS-27 (p=0.003, r value = -0.591) and with JAFS (total and after exclusion of hand component) (p=0.001 and 0.002, r value = -0.650 and -0.608 respectively). Significant correlations were observed between HGS and PedsQL (p=0.036).
Conclusions Patients with JIA have reduced HGS when compared to healthy children. HGS may be considered as a non invasive predictor of JIA disease activity and disability. Pediatric quality of life is adversely affected with decrease in HGS. HGS testing might be used a simple screening for disease activity in patients with JIA.
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Disclosure of Interest None declared