Knee Replacement & Continuous Passive Motion

4th Nov 2015

When it comes to rehabilitation equipment after your knee replacement, continuous passive motion machines can work wonders for people who have severe injuries. Available in the form of kits and devices aimed at particular areas of the body, there are many different types of continuous passive motion machines available. After you have surgery on a joint, your doctor may recommend that you use a continuous passive motion machine. This machine can help keep your joint flexible, as the CPM machine fully supports your joint. You can relax and let the machine do the work.

Luckily, knee replacement surgery has improved dramatically over the period of a few decades because of improved techniques, improved materials and improved understanding of knee physiology and function. More successful and durable knee replacement has had a big impact on clinical practice. According to patient plus, there are, broadly speaking, three types of knee replacement:

Unicompartmental Knee Replacement

  • This involves replacement of the medial or lateral tibiofemoral compartment only with components as below.
    • It has largely replaced osteotomy
    • It is usually used for osteoarthritis
    • It is NOT suitable for patients with rheumatoid arthritis

Unconstrained Bicompartmental Knee Replacement

  • This is the most common form of total knee replacement
  • The femoral component is metal and anatomically similar to the bone it replaces, with a groove for the patella
  • The tibial component is a flat metal platform with a plastic cushion and a stem extending into the tibia
  • The patella component is a dome-shaped piece of plastic anchored to a flat metal plate

Constrained Bicompartmental Knee Replacement

  • These are used much less often when considerable bone loss is involved, for example, with bone tumors
  • It is not possible to preserve the physiological joint action because the joint works like a fixed hinge.


If you are facing or have recently had knee replacement surgery, order your continuous passive motion machine from Medcom Group today.