Does Medicare Cover CPM Machines?

Continuous passive motion, or CPM, machines are covered by Medicare when prescribed by your doctor in limited situations following full knee replacement surgery. You will pay 20 percent of the cost to rent this equipment from an approved supplier for up to 21 days.

Medicare Coverage of Continuous Passive Motion Machines

Medicare covers continuous passive motion, or CPM, machines but only for a limited time in specific situations.

A knee CPM machine is covered by Medicare as durable medical equipment (DME) when it is prescribed by your doctor for use in your home following total knee replacement surgery.

Coverage is limited to a 21-day period following your surgery. The three-week coverage period begins the day you are discharged from the hospital.

Medicare considers use of CPM devices for longer periods of time or for other reasons investigational and not medically necessary. Therefore, the cost of these machines outside the limited scope described above isn’t covered by Medicare.

You can find a durable medical equipment supplier in your area by using Medicare’s online search tool.

You must rent your CPM machine from an equipment supplier that participates in Medicare.

If the supplier isn’t enrolled in Medicare, Medicare won’t pay the claims they submit, and there’s no limit on the amount a non-participating supplier can charge you.

CPM Machine Costs

CPM machines are covered by Medicare Part B. You will pay 20 percent of the approved cost to rent the machine, and Medicare will pick up the other 80 percent.

The Part B deductible applies.

You may pay less to rent your equipment if you have supplemental insurance, such as Medicaid or a Medigap policy.

If you’re enrolled in a Medicare Advantage plan, you can expect to pay the same 20 percent share for your device. Check with your plan provider to see if prior authorization is required.

Medicare covers only the cost to rent a knee CPM machine for up to 21 days after you return home from knee replacement surgery.

After that, you’re responsible for all costs.

DME suppliers may charge you for each additional day or week you keep the equipment after this three-week period.

According to different supplier websites, a two-week CPM rental can range between $300 and $400.

So, if it costs $375 to rent a knee CPM machine for 14 days, you’ll owe the supplier $75 with your Medicare insurance, assuming you’ve already met your Part B annual deductible.

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What Is a Continuous Passive Motion Machine?

A continuous passive motion machine is a piece of equipment meant to prevent stiffness, reduce swelling and improve your range of motion following orthopedic surgery.

CPM machines are most often used on knee joints, but there are versions made for other joints as well.

A CPM works by attaching to your knee or other limb where the surgery was performed.
The machine then constantly moves your knee or joint through a range of motion for a period of time.

A CPM machine is meant to supplement — not replace — at-home physical therapy following surgery.

You’ll receive instructions from your doctor or physical therapist for using the machine at home. Instructions will include the number of hours the device should be used each day and whether the settings should be increased over time.

You can control the machine’s speed, intensity and duration of passive motion. Settings can be adjusted through a handheld controller or tablet.

CPM machines include supportive padding, a power supply and a frame that adjusts to your body.

Your doctor will give you guidelines and goals to achieve with your CPM machine.

Last Modified: September 15, 2021

5 Cited Research Articles

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  2. CGS – Jurisdiction C. (2014, January 28). Payment Rules - Continuous Passive Motion Machines. Retrieved from
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  4. St. Luke’s Health System. (n.d.). Discharge Instructions: Using a Continuous Passive Motion (CPM) Machine. Retrieved from
  5. U.S. Centers for Medicare & Medicaid Services. (n.d.). National Coverage Determination (NCD) for Durable Medical Equipment Reference List (280.1). Retrieved from