A Feasibility Study of the Effect of Intra-Articular Corticosteroid Injection on Isokinetic Muscle Strength in Children With Juvenile Idiopathic Arthritis

Abstract

This study assessed the magnitude of changes in isokinetic muscle strength in children with juvenile idiopathic arthritis (JIA) before and after treatment with intra-articular corticosteroid injection and assessed the feasibility of a larger study of the same effect. Isokinetic dynamometry was used to measure peak knee extension and flexion torque in 12 children before and after treatment for unilateral knee arthritis. Extensor and flexor strength was reduced on the affected side before treatment (-0.56Nm/kg, p = .004 and -0.24Nm/kg, p = .02 respectively). Increases in extensor strength were observed at two weeks (p = .01) and twelve weeks postinjection (p = .03). Improvements at 6 weeks approached but did not reach statistical significance (p = .17). Improvements in flexor strength were not observed until 12 weeks postinjection (p = .03). Despite significant improvements in extensor strength, low peak knee extensor torque continued to be observed at 12 weeks (p = .01). Knee extensor and flexor strength is reduced in children with JIA with active arthritis and improves following intra-articular corticosteroid injection. Significant improvements in knee extensor and flexor strength were seen postinjection; however deficits in extensor strength were still evident at three months. Isokinetic dynamometry was safe and well tolerated in our sample of children with JIA with active arthritis.Juvenile idiopathic arthritis (JIA) is a relatively common and potentially debilitating disease affecting 1 in 1,000 children aged below 16 years (34). Early diagnosis and active therapeutic intervention are essential in minimizing the short McKay, Ostring, Chaitow, and Singh-Grewal are with the

Effect of Intraarticular Corticosteroid Foot Injections on Walking Function in Children With Juvenile Idiopathic Arthritis

“…In our study, children with JIA walked with reduced walking speed and decreased range of motion, predominantly in the sagittal plane. We did not measure muscle strength, but one could hypothesize that strength was diminished, as supported by the finding of reduced ankle power . In healthy children, reduced walking speed is associated with an increased ankle power to hip power ratio, indicating greater relative impact on the ankle .…”

“…Lelieveld et al concluded that only 23% of children with JIA met public health recommendations to perform >1 hour daily moderate to vigorous physical activity, compared to 66% in a healthy reference group . Inflammation surrounding affected joints leads to muscular weakness, which may persist when the disease is inactive . Children with a history of ankle involvement demonstrate reduced ability to generate ankle power during push‐off in walking , which may impact participation in more demanding physical activities such as running and jumping.…”

Dynamic knee joint function in children with juvenile idiopathic arthritis (JIA)

“…In this study a lower dynamic joint function especially extension torque in arthritic knee joints compared to healthy was found. McKay demonstrated reduced knee extensor strength using isokinetic dynamometer in children with JIA and active arthritis [ 38 ]. Hedengren found lower joint torque values in a subgroup of children with arthritis [ 19 ].…”

Application of Intra-articular Corticosteroid Injection in Juvenile Idiopathic Arthritis

“…Lanni et al found that treatment with IACIs in a considerable number of patients injected in single or multiple joints can induce sustained relief of synovitis and has good safety ( 39 ). McKay thought that the improvement of the strength of the extensor and flexor muscles was considered to be of clinical significance after active treatment of inflamed knee joints with IACIs ( 40 ). In 2010, Scott re-evaluated IACIs for children with JIA and confirmed that IACIs are a safe, rapid, and effective treatment method ( 9 ).…”

“…Therefore, after injecting corticosteroids into the joint cavity, an exercise program may be needed, and confirmation of persisting deficits in knee extensor strength indicates that specific intensive exercise or physical therapy should be carried out after IACIs to resolve the strength deficiency. This is not only to improve strength but also to improve function and solve biomechanical abnormalities in gait ( 40 ). In 2019, Elaine et al compared the group that was not splinted with the group that was splinted after IACI of the knee and concluded that the risk of recurrent arthritis was not statistically significant ( 48 ).…”