Iovera is a medical device that uses extreme cold to temporarily shut down specific nerves, blocking pain signals for up to 90 days. It’s FDA-cleared for relieving pain from knee osteoarthritis and for blocking peripheral nerve pain more broadly. The treatment works without drugs, implants, or surgery, and the entire procedure typically takes about 30 minutes in a doctor’s office.
How Iovera Works
The iovera system uses a process called cryoneurolysis, which means “nerve destruction through cold.” A handheld device delivers focused cold temperatures (between negative 20 and negative 80 degrees Celsius) to a targeted nerve through a thin needle-like probe called a Smart Tip. At those temperatures, the nerve fiber and its protective coating break down in a process called Wallerian degeneration. This stops the nerve from transmitting pain signals to your brain.
The key distinction from other nerve-blocking approaches: the nerve’s outer structure stays intact. Think of it like cutting the wiring inside an electrical cable while leaving the cable’s outer sheath in place. Because that outer structure remains, the nerve can regrow along its original path over the following weeks and months. Once it fully regenerates, sensation returns to normal. This is why the pain relief is temporary rather than permanent.
The device uses nitrous oxide as its cooling agent, delivered through the probe tip to create a precisely localized cold zone. The freezing effect stays confined to the targeted nerve, sparing surrounding tissue. Some probe configurations can also deliver electrical nerve stimulation from a separate stimulator, helping the doctor confirm they’ve located the correct nerve before applying the cold treatment.
What Iovera Is Used For
The FDA has cleared the iovera system for two main purposes: destroying tissue during surgical procedures by applying freezing cold, and producing lesions in peripheral nerves to block pain. It carries a specific indication for relieving pain and symptoms of knee osteoarthritis for up to 90 days. It is not indicated for use on central nervous system tissue (the brain or spinal cord).
For knee osteoarthritis, the treatment typically targets a sensory nerve branch near the kneecap called the infrapatellar branch of the saphenous nerve. Before treatment, doctors often perform a diagnostic nerve block with a local anesthetic to confirm that this specific nerve is responsible for your pain. If the anesthetic provides temporary relief, you’re considered a good candidate for the cryoneurolysis treatment.
Beyond osteoarthritis, clinicians use iovera for a growing range of pain conditions involving peripheral nerves. One of the more notable applications is before total knee replacement surgery, where the goal is to reduce pain during recovery and potentially lower the need for opioid painkillers.
Iovera Before Knee Replacement Surgery
A study published in the National Institutes of Health comparing 29 knee replacement patients who received cryoneurolysis against 28 who did not found some encouraging patterns. Patients in the cryoneurolysis group had a shorter average hospital stay (2.5 days versus 3.5 days) and used fewer opioid painkillers both during their hospital stay and in the weeks afterward. At the four-week follow-up, the cryoneurolysis group’s average opioid use was roughly half that of the control group (313 versus 561 morphine milligram equivalents), though the difference did not quite reach statistical significance in this small study.
The logic behind preoperative use is straightforward: if you numb the sensory nerves around the knee before surgery, you wake up with less pain, need fewer painkillers, and can start physical therapy sooner. For patients concerned about opioid use after a major joint surgery, this is a meaningful potential benefit.
What the Procedure Feels Like
The treatment is done in a clinic or doctor’s office, not an operating room. Your doctor first applies a numbing agent, either as a topical cream or a small injection, to minimize discomfort at the treatment site. Once the area is numb, the iovera probe is inserted through the skin to reach the target nerve. The cold treatment is applied, and the entire visit typically wraps up in about 30 minutes.
Most people describe feeling pressure or a cold sensation during treatment, but the local anesthetic keeps it from being painful. There is minimal to no downtime afterward. Most people return to their normal activities immediately following the procedure, with no splints, bandages, or special recovery instructions. Some mild soreness, swelling, or bruising at the insertion site is common and typically resolves within a few days.
How Long the Relief Lasts
Pain relief from a single iovera treatment is clinically proven to last up to 90 days. The actual duration varies from person to person depending on how quickly the treated nerve regenerates. Some people notice pain gradually returning around the two-month mark, while others get the full three months of relief.
Because the treatment is temporary by design, it can be repeated every 90 days if needed. There are no drugs building up in your system and no implanted hardware, so repeat treatments don’t carry the compounding risks that come with some other pain management approaches. This makes iovera a practical option for people who want ongoing pain control without committing to surgery or long-term medication use.
Who Iovera Works Best For
The strongest evidence supports iovera for people with knee osteoarthritis who haven’t found adequate relief from physical therapy, anti-inflammatory medications, or injections, but who aren’t ready for or don’t want knee replacement surgery. It fills a gap between conservative treatments and major surgery.
It also fits well for people preparing for knee replacement who want to reduce their reliance on opioid painkillers during recovery. And because it targets peripheral nerves specifically, it can be applied to pain conditions in other joints and areas of the body where a specific sensory nerve can be identified as the source of pain signals. The ankle osteoarthritis research, for instance, uses the same cryoneurolysis principle on nerves around the ankle joint.
Iovera is less suited for pain that originates from the central nervous system, widespread pain conditions like fibromyalgia, or situations where the pain source can’t be traced to a specific peripheral nerve. The diagnostic nerve block performed beforehand serves as a useful screening tool: if temporarily numbing the target nerve doesn’t relieve your pain, cryoneurolysis of that nerve won’t either.