A knee CPM machine — short for Continuous Passive Motion machine — is a motorized rehabilitation device that gently and automatically bends and straightens your knee while you rest. You simply place your leg in the padded cradle, set the angle and speed according to your doctor's instructions, and the machine does all the work. It is commonly prescribed by orthopedic surgeons after knee replacement surgery, ACL reconstruction, meniscus repair, and other knee procedures to help restore range of motion, reduce swelling, and prevent scar tissue from forming in the joint.

Yes — knee CPM machine, continuous passive motion machine, knee bending machine, and flexing machine for the knee all refer to the same type of rehabilitation equipment. You may hear your surgeon, physical therapist, or discharge nurse use any of these terms. At Complete Medical Supply, we carry knee CPM machines available for weekly and monthly rental at our Houston Heights location, serving patients across the greater Houston and Cypress areas.

Your surgeon prescribes a knee CPM machine because early, controlled movement of the joint is one of the most effective ways to speed up recovery and reduce complications. Keeping the knee completely still after surgery allows scar tissue to build up inside the joint capsule, which can permanently limit your range of motion and lead to a condition called arthrofibrosis. The CPM machine keeps the joint moving safely and passively — without requiring you to actively exercise a knee that is still healing. Most patients who use a CPM machine consistently after surgery regain range of motion faster and experience less stiffness compared to those who do not use one.

Knee CPM machines are most commonly prescribed after: Total knee replacement (knee arthroplasty) — the most common reason CPMs are prescribed. Surgeons typically prescribe 4 to 6 weeks of daily CPM use following a total knee replacement to help the new joint achieve full flexion. ACL reconstruction — CPM therapy after ACL repair helps maintain range of motion during the early healing phase while the graft integrates with the surrounding tissue. Meniscus repair or meniscectomy — following meniscus surgery, controlled passive motion helps reduce swelling and restore mobility without placing weight or active stress on the healing tissue. Partial knee replacement — unicompartmental knee surgery patients also benefit from early controlled passive mobilization. Cartilage restoration procedures — microfracture surgery and other cartilage repair techniques often require extended CPM therapy to promote proper cartilage regrowth. Knee manipulation under anesthesia — if a patient develops significant stiffness following a prior knee surgery, CPM therapy is often part of the follow-up protocol. Chronic knee stiffness or post-traumatic arthritis — some patients use CPM machines as part of an ongoing management plan for chronic conditions that limit joint mobility.

At Complete Medical Supply, our knee CPM machine rental rates are: Weekly rental: $200 per week Monthly rental: $425 per month Every rental includes our knee pad comfort kit at no additional charge. This is the padded leg cradle accessory that most other medical equipment providers charge separately — typically around $50 — or require you to purchase outright before you can begin using the machine. We include it in the rental price because we believe you should have everything you need to start your recovery the moment you walk out of our store. If you are comparing prices between providers, make sure you are comparing apples to apples. Our $200 weekly rate includes the knee pad kit. A competitor advertising a lower weekly rate may still require you to purchase the pad kit separately, which can close or eliminate the price difference entirely.

The duration of your rental depends on your surgeon's protocol and how your recovery progresses. Most patients fall into one of these ranges: Total knee replacement: 4 to 6 weeks is most common, though some surgeons prescribe use for up to 8 weeks. ACL reconstruction: typically 2 to 4 weeks depending on the graft type and your surgeon's specific protocol. Meniscus repair: usually 2 to 4 weeks. Other procedures: your surgeon will specify the number of weeks and the daily hours of use on your prescription or discharge paperwork. If you are unsure how long you will need the machine, we recommend starting with a weekly rental and extending as needed. Our monthly rate of $425 is the better value if you know upfront you will need it for four weeks or longer.

Your surgeon will typically provide a CPM prescription or include specific settings on your discharge paperwork — including the starting angle, maximum angle, and daily hours of use. Bring that documentation with you when you come in. Our staff will use those settings to configure the machine for you before you leave. If you are coming in right after discharge and do not have your paperwork yet, call us at 713-880-4000

Complete Medical Supply is located at 1732 W. 18th Street in Houston's Heights neighborhood — near the intersection of 18th and Ella Boulevard. We also serve patients in Cypress and throughout the greater Houston area including Katy, Sugar Land, Pearland, Spring, The Woodlands, Tomball, Conroe, Bellaire, Galleria, Midtown, Montrose, Memorial, Pasadena, Missouri City, and Jersey Village. Call us at (713) 880-4000 to confirm availability before making the trip.

In most cases, yes — subject to availability. Call us at (713) 880-4000 and we will confirm whether a machine is in stock and ready for same-day pickup. We recommend calling before making the trip so you are not left waiting. Most patients coming straight from hospital discharge or from a pre-op appointment are able to get their CPM machine the same day.

Most patients describe CPM therapy as mild discomfort rather than pain — especially in the first few days when the knee is most swollen and sensitive. The machine moves slowly and you control the range of motion through the angle settings. If you experience sharp or severe pain during use, stop the machine and contact your surgeon. Some tightness or a pulling sensation at the limit of flexion is normal. As swelling decreases over the first week, most patients find the machine becomes significantly more comfortable to use.

Renting is almost always the right choice for post-surgical recovery. Knee CPM machines are used for a short, defined window — typically 2 to 6 weeks — after which you no longer need the device. Purchasing a new CPM machine outright can cost anywhere from $3,000 to $5,000 or more depending on the model. Our rental pricing gives you access to a clean, properly functioning machine for the duration of your recovery at a fraction of the purchase price, with no equipment sitting unused in your home afterward. Unless you anticipate needing the machine repeatedly for multiple surgeries or family members, renting is the practical choice for the vast majority of patients.