Pediatric Rheumatology Online Journal → June 2003 → Rehabilitation→ Abstract #71

PILOT STUDY: IMPROVEMENT OF JOINT USE IN QUIESCENT JUVENILE IDIOPATHIC ARTHRITIS (JIA) WITH SPECIALIZED NEUROMUSCULAR TRAINING (SNT) AFTER BIOMECHANICAL TESTING

H. I. Brunner, M. V. Paterno, P. G. Melson, K. R. Ford, G. D. Myer, D. J. Lovell, T. E. Hewett

¹Rheumatology & Sports Medicine Biodynamic Center, Cincinnati Children's Hospital, Cincinnati, OH, United States

Background: Patients with active JIA often receive physical therapy (PT) to conserve muscle strength and joint range of motion, while those with inactive disease and normal joint ranges do not.
Objectives: 1. To assess the effects of JIA on gait & motion patterns of apatient with quiescent disease; 2. To determine the benefits from SNT.
Method: Pilot subject: A 10-yr old girl with currently quiescent JIA; history of left knee monoarthritis; active in soccer & basketball; routine PT assessment:normal . Testing/Intervention: Initial kinematic (motion) and kinetic (force) testing was followed by SNT (2 sessions/wk x 4 wks). Effects of SNT were assessed by repeat biomechanical testing, whose results were compared to baseline testing and to age/sex-matched control data.
Results: The subject's gait deviated from normal (±1SD) with narrowed step width and increased knee flexion at heel strike. Landing analysis (box drop test) showed increased & imbalanced [right (R) vs left (L) leg> peak impact forces [normal: 1x body weight (BW). SNT led to normalization of heel strike & step width and to an important decrease of peak impact forces on box drop test [Pre-SNT: R/L at 3.9x BW / 2x BW vs Post-SNT: R/L at 2.7 xBW / 1.4x BW>. Imbalance of the peak impact forces decreased by 46%. The initially abnormal strength ratio between knee flexors/extensors measured on a dynamometer at high speed normalized & equalized [Pre-SNT: R: 10.9/26.7= 41%, L: 9.6/25= 38%; Post-SNT: R: 20.2/31.5= 64%, L: 204/31.5= 64%>.
Conclusion: Patients with clinically quiescent JIA and normal routine PT assessment may have abnormal biomechanics, placing them at higher risk for injuries and joint degeneration. Even short-term SNT may result in normalization or measurable improvement of the biomechanics of gait & athletic movements of these patients. Use of kinematic and kinetic testing to objectively assess patient joint use and muscle balance appears promising.