What is Continuous Passive Motion? The term, coined by Dr. Robert B. Salter, Professor of Orthopedic Surgery at the Hospital for Sick Children in Toronto, describes the treatment protocol of applying slow, rhythmic, and continuous movement to joints immediately following joint injury or surgery. Dr. Salter reasoned that since intermittent motion was better for joints than total immobilization, continuous motion should be even superior. Furthermore, given the fatigability of skeletal muscle, it was clear that this motion must be PASSIVE rather than ACTIVE.
Dr. Salter, along with the ever-growing number of supporters of continuous passive motion, has demonstrated clinically that CPM, rather than immobilization, is the preferred treatment for joint injuries. Immobilization has been shown to inhibit the circulation of synovial fluid, thus starving the joint cartilage of nutrients. Furthermore, it has been shown to promote the development of adhesions and scar tissue. CPM, however, has been shown to nurture and regenerate cartilage while maintaining joint nutrition, lubrication, and successful growth of new cartilage. Continuous passive motion also helps to maintain the patient's range of motion (ROM) in the affected joint, which in turn reduces rehabilitation time.
As Dr. Salter phrased it, "Joints were meant to move."
It is movement, particularly after trauma, which is vital to the maintenance of healthy joint function.