Continuous Passive Motion Machines

Continuous passive motion (CPM) is a type of treatment in which a machine moves a patient's joints, sometimes for hours at a time, without the patient's having to contract her or his muscles to create the motion. A CPM machine is programmed to flex and extend the joint a preselected number of times and through a particular range of motion. CPM is used to rehabilitate a patient's joints following injury to, or surgery on, articular tissues, including cartilage, tendons and ligaments.

Advantages of Continuous Passive Motion Machines

It is important to move a joint as soon as it has been operated on; if not, the patient risks contracture, which affects the joint's range of motion (ROM). However, postoperative pain often causes a patient to avoid moving the joint. CPM aids in recovery without straining the patient's muscles, reducing pain, minimizing scar-tissue growth, decreasing recovery time, increasing flexibility, and promoting joint-surface and soft-tissue healing.

Applications for Continuous Passive Motion Machines

CPMs are used when joints in the extremities need rehabilitating, which is usually necessary after a patient undergoes the following:

  • Total knee arthroplasty
  • Anterior cruciate ligament (ACL) surgery
  • Tibial osteotomy
  • Periosteal transplantation
  • Rotator cuff repair
  • Metacarpophalangeal (MCP) joint arthroplasty

CPMs are also used to treat adhesive capsulitis (frozen shoulder).

Additional Resources