Continuous passive motion ("CPM") therapy is used in post-operative rehabilitation to aid in the recovery process following several types of joint surgeries.  After extensive joint surgery, patient attempts at joint flexion can cause considerable pain, dissuading the patient from effective joint motion.  Failure to achieve proper rehabilitative flexion can lead to stiffening of the tissue surrounding the joint.  This condition can eventually cause the formation of scar tissue, resulting in a limited range of motion in the joint.

A continuous passive motion (CPM) machine uses passive motion to move the joint gradually and slowly, without engaging the patient's muscles.  CPM machines are most often applied post-operatively and can be used in both inpatient and outpatient therapy regimens.  The physcian will prescribe usage instructions, including the speed of the machine, the duration of usage, amount of motion, and the rate of motion increase.

Various studies have concluded that patients using a CPM machine following surgery generally require less pain medication than those who do not use the CPM machine after the same type of surgery*.

*Studies showing patients require less pain medication after surgery when using a CPM machine:

Beneficial Effects of Continuous Passive Motion After Total Condylar Knee Arthroplasty.  D. Johnson, MD.  Ann R Coll Surg Engl, November 1992, Vol. 74, No. 6.

The Value of Continuous Passive Motion in Total Knee Arthroplasty.  S. Wasilewski, MD et al. Orthopedics, March 1990, Vol. 13, No. 3.

Continuous Passive Motion After Total Knee Arthroplasty.  Vince MD, et al.  The Journal of Arthroplasty, December 1987, Vol. 2, No. 4.