Preliminary evidence for techniques used to optimally align (tune) fixed ankle-foot orthoses in children

Abstract

An angle of 10° to 12° incline between the anterior border of the tibia (shank) and the vertical (SAV) at mid-midstance has been recommended as a starting point from which the "moment arm" at the knee can be optimized (tuned) in children wearing fixed ankle-foot orthoses. The aim of this study was to document the SAV and "moment arm" at the knee throughout stance in normally developing children. Data were collected from 11 healthy children aged 5 to 16 years, and SAV and "moment arm" at the knee plotted throughout stance, both barefoot and shod. The mean (standard deviation) SAV at mid-midstance was 11.4° (3.4°) barefoot and 10.5° (3.6°) shod. The mean (standard deviation) "moment arm" at the knee (normalized to leg length) at mid-midstance was 2.5% (1.7%) barefoot and 1.3% (2.4%) shod. The study provides preliminary evidence for current tuning techniques. © 2011 American Academy of Orthotists & Prosthetists.