Abstract: The present invention relates to a virtual reality feedback system to measure trunk orientation of a low back pain patient, and then displaying the measurement information on a display device for the benefit of the patient.

Abstract: A method and apparatus for joint controlled training of different motoric units for development of functional muscle strength and proprioceptiviety, wherein the direction of action of the resistance is adjusted in relation to the muscle groups or motoric units to be trained. In the method and apparatus all joint positions are arrested for the joints associated with the groups of muscles or the motoric units to be trained. The apparatus incorporates orthoses (1, 4, 5) for arresting positions of all joints which are affected by the muscle groups or motoric units to-be-trained, as well as a non-resilient strap (8). The strap (8) facilitates adjustment of the angle under which a load (12) is applied.

Abstract: An apparatus to monitor and record, for an industrial environment, two natural frequencies with respect to a "seated spinal system", namely, approximately 10 Hz and approximately 4 Hz, the natural resonant frequencies of the spine. Raw acceleration signals are amplified, conditioned and filtered to allow only 20 Hz or less to pass. The signals are then divided into two respective channels, namely, below 20 Hz and below 8 Hz, following parallel paths through an amplitude detector and through a zero crossover detector, rectifier and digital filter. In each path the amplitude detector controls a storage flip-flop, which enables an associated decade counter when amplitude criteria are met. The digital filter supplies an output, via an AND gate, to the counter if both amplitude and frequency criteria are met. Thus, a count is stored in the counter if both amplitude and frequency criteria are met. Each channel has an LED display which can be turned on, after exposure, to display the number of events recorded.