The effect of planar constraint on the definition of the wrist axes of rotation.

摘要: Abstract Instantaneous helical axes (IHAs) and screw displacement (SDAs) are commonly used to investigate joint functional of rotation. In the wrist, these have often been obtained through in vitro motion analysis. These definitions then employed for vivo applications, such as design implants or development musculoskeletal models. However, unguided motions are, by definition, affected activity muscles. Previously published data has disagreed on relative position orientation two primary rotation i.e. radioulnar deviation (RUD) axis with respect flexion-extension (FE) axis. An study comparing FE RUD IHAs SDAs guided motions, replicate conditions, 23 healthy participants was conducted using optical capture. Guided were performed hand forearm flush against a flat surface. The differed (p = 0.019, p = 0.001) between (0.1 ± 4.3 mm, 93.5 ± 16.0°) (1.6 ± 4.0 mm, 107.8 ± 17.7°). This indicates that use different constraints, not physiological differences, is cause differences positions orientations literature. Thus, practice wrist especially involving FE, may be inappropriate care must taken account any constraint motion. It recommended investigators define specifically their refer literature featuring desired levels constraint.