A simple test used by the physical therapist to evaluate the condition of the test is the tabletop test. This test will show if you can flatten your palm and fingers on a flat surface. This test will also serve to follow the progression of the disease and of the treatment.  The physical therapist should also evaluate the movement of the fingers and hand, assess what functional tasks the patient can and cannot do.
If occupational factors are part of the problem then changes to consider include pacing, rest breaks, reducing repetition and force, posture, and the use of ergonomically designed tools and equipment to make work tasks easier. 
For Dupuytren’s contracture, the physical therapy treatment consists in a massage of the hand and fingers to relax the fascia and give it a bit more of mobility; a deep tissue massage over all the nodules that are present in the palm of the hand and fingers to undo the nodules, thus giving more mobility to the palmar fascia; and finally, physiological and accessory mobilization of the wrist, of the carpal bones, of the metacarpal bones and of the first, second and third metacarcarpal-phalangeal joints. The physical therapist can also advise the patient to wear a splint.
If the surgery is needed, physical therapy is still very important afterwards to a rapid and successful recovery of the hand mobility and function.
 Dupuytren’s Contracture. Physiotherapy in Leeds for Hand
 Dupuytren’s Contracture. RSIA: Repetitive Strain Injury Association