Gait Adaptations in Youth With Juvenile Idiopathic Arthritis

Abstract

ObjectiveJuvenile idiopathic arthritis (JIA) affects body structure and function and physical activity outcomes. The present study was undertaken to examine differences in gait kinematics during fixed‐speed treadmill walking for youth with JIA and typically developing (TD) youth.MethodsSagittal plane gait kinematics were obtained using a 12‐camera system (Motion Analysis) for youth with JIA (n = 30) and their age and sex‐matched TD peers (n = 30). Outcomes included disease activity, pain, well‐being, and peak sagittal hip, knee, and ankle joint angles. Kinematics were analyzed for the indexed leg (IL) (i.e., the affected leg of participants with JIA) compared to the dominant leg of TD participants and for the contralateral leg (CL) (i.e., the less/not affected leg of participants with JIA) compared to the nondominant leg of TD participants. Kinematics differences were investigated using multivariate Hotelling's T2 statistic (paired samples; α = 0.05) and simultaneous 95% confidence intervals (95% CIs). Potential confounders (age, sex, body mass index) were assessed using linear mixed‐effects models with random effect for pairs.ResultsYouth with JIA had low disease activity, pain, and disability scores. Deviations in bilateral joint angles were observed (IL P = 0.015, CL P = 0.009). Youth with JIA walked with greater initial hip flexion (mean difference IL 2.8° [95% CI –0.6, 6.2]; CL 3.0° [–0.9, 6.9]) and lower knee extension (mean difference IL –2.2° [95% CI –4.4, 0.1]; CL –3.3° [–7.4, 0.8]), and lower hip extension during terminal stance (mean difference IL 3.4° [95% CI –0.3, 7.0]; CL 4.0° [1.0, 7.0]).ConclusionDespite low disease activity, youth with JIA avoided the close‐packed knee position, commonly associated with joint inflammation and pain. These findings highlight secondary consequences of JIA and inform targets for physical therapy management for youth with JIA.

Vertical Drop Jump Performance in Youth With Juvenile Idiopathic Arthritis

“…Data processing. Kinematics data were processed using EVaRT (Motion Analysis) and hip, knee, and ankle joint angles were computed using Visual3D (C-Motion) (14). Joint angle time series were normalized to the first support phase of the VDJ (101 data points) by extracting foot contact events for the right and left feet.…”

Consequences of Juvenile Idiopathic Arthritis on Single Leg Squat Performance in Youth

“…Joint angles were analyzed with respect to the indexed leg (the affected leg of participants with JIA or dominant leg of control participants) and the contralateral leg (the unaffected or less affected leg of participants with JIA or the nondominant legs of control participants). In line with previous approaches (19), the indexed leg was identified by the study rheumatologist, and in cases of a bilateral knee involvement, the indexed leg was identified by the participant as the leg that they felt was generally affected worse. The dominant leg of control participants was identified by determining with which leg they preferred to kick a ball.…”

“…This study employed a matched pair cohort study design, matching youth with JIA with their healthy peers (control group) based on the closest match in age (within 1.5 years) and sex. Recruitment details for this cohort have been pre viously reported by Kuntze et al (19). Participants with JIA were recruited sequentially as they presented to their acting physician and physical therapist at the Pediatric Rheumatology clinic at the Alberta Children's Hospital and the Richmond Road Diagnos tic and Treatment Centre Rheumatology Clinic in Calgary.…”

“…Details of disease activity, functional capacity, and cohort characteristics have been previously reported by Kuntze et al (19). Briefly, disease activity was recorded by the same study physician (SB) using the clinical Juvenile Arthritis Disease Activity Score in 10 joints (cJADAS‐10) guidelines.…”

“…Further, individuals with JIA appear to be more sensitive to mechanical and thermal stimuli, even in the absence of pain or active disease (14). Differ ences in joint biomechanics in individuals with JIA during walking and jumping (15)(16)(17)(18)(19)(20) have been reported, providing evidence on body structure and function alterations, which are likely asso ciated with underlying deficits in muscle strength and altered neuromuscular control. Differences in jump landing mechanics of youth with JIA (20) are particularly interesting because they indicate a stiff landing strategy, which has been suggested as a risk factor for lower extremity injury in female youth athletes (21,22).…”