I work for a company attempting to introduce a European model of rehabilitation known as Medical Exercise Therapy
The main goal is to re-establish "normal function" of the locomotor system. To reach this goal we use the most natural function of the locomotor system of the human body, the active movements. The active movements, exercises, are specific designed in ROM, speed and quality of motion to reach this goal. Dosage of the number and resistance of the exercises are based on a mathamatical model. The fundamentals of this model are adapted from the knowledge of work physiology. MET is an "objective method" to use in rehabilitation. Accurate dosage to increments of 100 grammes and even dosed deloading of an exercise make it possible to work at the possibilities of the patient
MET was originally developed over 30 years ago. I would be more than happy to send more info and put you in touch with therpapists using this approach.
Kind regards
Rob