Pediatric Rheumatology Online Journal → June 2003 → Rehabilitation→ Abstract #72

3D-GAIT ANALYSIS - A METHOD TO MEASURE THE EFFECT OF JOINT INJECTIONS IN CHILDREN WITH JUVENILE IDIOPATHIC ARTHRITIS

E. Brostrom,¹ Y. Haglund-Akerlind,² S. Hagelberg.³

¹Department of Women and Child Health, Karolinska Institute, Stockholm, Sweden; ²Department of Orthopaedics; ³Department of Rheumatology, Astrid Lindgren Children's Hospital, Stockholm, Sweden

Intraarticular corticosteroid injections (ICI) remain an important therapy for children with juvenile idiopathic arthritis (JIA), in order to decrease joint swelling, alleviate pain and enabling the the child to preserve mobility and strength. The outcome regarding gait after ICI has not previously been described in detail. The aim of this study was to compare 3-dimensional computerized gait analyses of 14 children with JIA, before and after ICI.
Method: Fourteen children with polyarticular JIA, aged 7-16 yrs, participated. All children were treated with ICI in lower extremities. 3D-gait analysis was performed using a six-camera motion analysis system (Vicon). Each subject walked with a self-chosen speed over two force plates (Kistler). Pain-measurement (visual analogue scale=VAS) and gait analysis were performed 1-4 days pre- and 8-17 days post-ICI. Joint moments were estimated for the ankle, knee and hip joints at the sagittal plane. Moment is the rotary force that causes the joint to move and is defined as the product of the force and its lever arm.  The Wilcoxon test was used for statistical analysis.
Result: VAS pain rating differed significantly (p=0.01) between pre- (27mm) and post- sessions (12mm). The children showed faster mean walking velocity (m/s) and single support (s). Furthermore, the hip extension moment at heel-strike and hip flexion moment at toe-off increased significantly (p=0.02 & p=0.006). The knee extension/flexion moment did not differ significantly pre- and post-treatment with ICI, whereas plantarflexor moment showed a stronger push-off, seen as an increased peak moment at terminal stance.
Conclusion: The main finding of the study was that children with JIA had a faster mean walking velocity and increased hip and ankle moment at heel-strike and toe-off after ICI. This 3D-gait analysis method allows a fast and easy method to measure effects of ICI in children with JIA, and may offer the clinician detailed information for prudent treatment decisions.