Payment Rules - Continuous Passive Motion Machines - Revised

DME MAC Joint Publication
Posted July 8, 2022

Medicare covers continuous passive motion devices (CPM) under the Durable Medical Equipment Benefit. Reasonable and Necessary (R&N) requirements are set out in CMS National Coverage Determination 280.1. The NCD states:
Continuous passive motion devices are devices Covered (sic) for patients who have received a total knee replacement. To qualify for coverage, use of the device must commence within 2 days following surgery. In addition, coverage is limited to that portion of the 3-week period following surgery during which the device is used in the patient's home. There is insufficient evidence to justify coverage of these devices for longer periods of time or for other applications.

Note that CMS has clarified to the DME MACs that in addition to a total knee replacement, a CPM device is also covered following the revision of a major component of a previous total knee replacement (i.e., tibial components or femoral component).

Additional billing instructions are provided in CMS Claim Processing Manual (Internet-only Publication 100-04) Chapter 20, Section 30.2.1 which states:
Contractors make payment for each day that the device is used in the patient's home. No payment can be made for the device when the device is not used in the patient's home or once the 21 day period has elapsed. Since it is possible for a patient to receive CPM services in their home on the date that they are discharged from the hospital, this date counts as the first day of the three week limited coverage period.

Coding Guidelines

Continuous Passive Motion devices are classified under two HCPCS codes:


Recent questions regarding the exact nature of these devices reveal confusion regarding the nature and functionality of these devices. These coding guidelines clarify the types of products described by the CPM codes.

The first test of any durable medical equipment is that it be durable and capable of repeated use over the expected five-year useful life expectancy. Elastic, fabric, single use, or light plastic devices are not durable and do not meet the test for DME.

Secondly, the equipment must be capable of continuous passive motion of the affected limb. These characteristics mean that the device must have inherent within itself the ability to move the affected limb:

  • in an appropriate plane of motion
  • in a continuous fashion
  • at the same rate of speed
  • for a prescribed length of time
  • with adjustable limits of range of motion
  • with an identical range of motion in each cycle
  • without any input from the patient by the contralateral or other limbs
  • with easily accessible safety or cutoff switches

These characteristics require that the device be electrically powered, either by AC current or battery. Battery powered models must have an AC adapter for long term use. CPM machines must meet all these characteristics in order to be coded as E0935 or E0936.

Patient-controlled stretch devices are not considered CPM devices and must not be billed using codes E0935 or E0936. These devices are considered exercise equipment and are coded A9300.

Coverage and Documentation

Based upon the NCD, Continuous passive range of motion devices (CPM) are covered by Medicare only if all of the following are met:

  • CPM treatment is started after a total knee replacement or a revision of a major component of a previously performed total knee replacement. CPMs are not covered after any other type of knee or joint surgery.
  • CPM treatment must be applied within 48 hours of surgery to be eligible for Medicare coverage

Claims for items that do not meet these criteria will be denied as not reasonable and necessary.

Coverage is limited to 21 days from the date of surgery. The DME MAC should be billed only for those days of CPM treatment after discharge from the hospital.

The supplier must have a standard written order signed and dated by the ordering physician in their file prior to submitting a claim for a CPM.

In the event of an audit there must be information in the medical record showing that the coverage criteria are met.

When billing for a CPM (HCPCS code E0935), all of the following documentation must be included with the claim:

  • Type of knee surgery performed; and,
  • Date of surgery; and,
  • Date of application of CPM; and,
  • Date of discharge from the hospital

Claims submitted without this required information will be denied as not reasonable and necessary.

Refer to the Supplier manual for additional information about coverage, coding and documentation requirements.

For questions about correct coding or products not listed on the DMECS Product Classification List (PCL), contact the PDAC HCPCS Helpline at (877) 735-1326 during the hours of 9:30 a.m. to 5:00 p.m. ET, Monday through Friday. You may also visit the PDAC website This link will take you to an external website. to chat with a representative or select the Contact Us This link will take you to an external website. button at the top of the PDAC website for email, FAX or postal mail information.

Publication History

Date of Change Description
January 23, 2014 Originally Published
July 08, 2022 Updated detailed written order to standard written order – effective January 1, 2020


Last Updated Jul 05 , 2022