Movement analysis of scoliotic subjects using Fastrak.

An attempt has been made to simplify the measurement of composite movement involving abnormal rotation in scoliosis, which is considered to have an important role in the diagnosis and treatment of the condition. Analysis of three-dimensional movement provides pertinent information concerning the morphological description of scoliotic deformities. The description of this movement is of clinical interest for aiding diagnosis and/or prognosis of spinal deformity evolution. Previous studies have indicated that idiopathic scoliosis is a three-dimensional deformity accompanied by a generalised torsion phenomenon and attempts have been made to associate the geometric torsion index with the curvi-linear shape of idiopathic scoliosis. Although previous investigations have documented the three-dimensional reconstruction of scoliotic spine, most methods either expose the subject to a high level of radiation, as in stereo-radiographs, or demand a high degree of technical input and time, as in video based gait analysis systems. This study employs an electro magnetic field capturing system (FASTRAK) to estimate the spinal movements. This simple system is inexpensive and highly portable. Furthermore, it can give instant graphic and numerical values of the composite movement. The results of this study indicate the usefulness this system in the diagnosis of scoliosis and highlights the possibility of its uses in screening school children and other surveys.