Abstract- A non-invasive
method of measuring pelvic and lumbar spinal movement during walking has been
developed. Targets attached to the subject reflect light from stroboscopic lamps
mounted near to each of three television cameras which are interfaced to a computer.
The targets' locations are identified by the interface and stored as coordinate
pairs. From the two-dimensional data from two cameras, three-dimensional data
are derived and the relative movements of the lumbar spine and pelvis can be
calculated.
The ranges of spinal and pelvic movements in a group of twenty-two normal males
have been measured. The mean values of spinal motion were 5.1° in the sagittal
plane, 9.3° in the coronal plane and 8.3° axial rotation. The corresponding
pelvic movements were 4.0° in the saggital plane, 7.7° in the coronal
plane and 11.2° axial rotation.
The system is useful to document abnormalities and to record the effects of
treatment.