Overview
Peripheral nerve stimulation, or PNS, is a minimally invasive treatment for some types of long-lasting pain. For the knee, a very thin wire is placed near the genicular nerves, the small nerves that carry pain signals from the knee. The wire sends mild electrical pulses that may change how those pain signals reach the brain. PNS may help some people with chronic knee pain from osteoarthritis, or ongoing pain after a knee replacement. It does not repair the knee, and results vary.
Watch: how peripheral nerve stimulation works
Video: “An Overview of SPRINT PNS” from SPR on YouTube. SPRINT PNS is one brand of peripheral nerve stimulation system, made by SPR Therapeutics. GSMC may recommend a different system based on your needs. It loads from youtube-nocookie.com only when you press play. Shown for general education; GSMC did not produce it. Watch on YouTube
What it is
In PNS, one or more thin leads (wires) are placed through a needle near a target nerve. The leads connect to a small stimulator. There are two general types of systems:
- Temporary systems: the lead is worn for a set time, often about 60 days, and then removed in the office. The stimulator is worn on the skin.
- Long-term (implanted) systems: after a successful trial, a lead and a small device are placed under the skin and can stay in place long term.
Several companies make PNS systems. Our physicians choose a system based on your needs, and no brand can promise a result.
Who it's for
PNS for the knee may help people who have:
- Chronic knee pain from osteoarthritis that has not improved enough with therapy, medicines or injections
- Ongoing knee pain after a knee replacement or other knee surgery
- People who are not ready for, or are not good candidates for, knee replacement surgery
- People who want to reduce their use of pain medicines
What the procedure involves, step by step
- Before: we review your history, exam and imaging. A test genicular nerve block may be used to see whether these nerves are a source of your pain. Some medicines, such as blood thinners, may need to be paused with approval from the prescribing doctor.
- Placement: in an outpatient visit, the skin is numbed. Using ultrasound or X-ray guidance, your physician places one or more thin leads through a needle near the genicular nerves.
- Setup: the lead connects to a small stimulator. Your care team adjusts the settings so the stimulation covers your pain area. Most people feel a light tingling or pulsing.
- Use at home: you use the stimulator during daily life and track your pain and activity.
- Follow-up: with a temporary system, the lead is removed in the office at the end of the treatment period, which usually takes a few minutes. If a long-term system is chosen, it is placed in a separate procedure.
Recovery and what to expect
- Most people go home the same day and return to light activity within a day or two.
- Keep the lead site clean and dry, and follow instructions about showering and activity.
- Some people notice a change in pain during treatment. For others it takes longer, and some people do not improve.
- With temporary systems, some people have relief that lasts after the lead is removed, and others do not.
Candidacy: who may or may not be a good fit
May be a good fit: people with chronic knee pain from osteoarthritis or after knee surgery whose pain has not improved enough with other care.
May not be a good fit: people with an infection in or near the knee, a loose or failing knee implant, a bleeding problem, certain implanted heart devices, skin problems that limit the use of adhesive, or pain that needs another fix first. Pain after knee replacement should be checked for infection or implant problems before PNS is considered. Research on PNS for knee pain is still growing.
Risks in brief
Risks include skin irritation from the bandage or adhesive, infection at the lead site, bleeding or bruising, and the lead moving or breaking. Small lead fragments can, rarely, remain under the skin. Pain may not improve. We will review your specific risks.
Alternatives
Other options may include physical therapy, weight management, bracing, medicines, joint injections, genicular nerve radiofrequency ablation, PRP (self-pay in most cases) or knee replacement surgery referral.
Frequently asked questions
How is PNS different from genicular nerve radiofrequency ablation?
Radiofrequency ablation uses heat to interrupt the nerves. PNS uses mild electrical pulses and does not destroy the nerve.
Will I feel the stimulation?
Many people feel a light tingling or pulsing. Some settings are barely felt.
Is PNS permanent?
It depends on the system. Some are used for about 60 days and then removed. Others can stay in place long term after a successful trial.
Can PNS help pain after a knee replacement?
For some people, yes. We first make sure the pain is not from an infection or a problem with the implant.
Can I shower with the lead in place?
Usually yes, with care. Your care team will explain how to protect the lead site.
Can I still have knee surgery later?
Yes. PNS does not rule out surgery later.
Insurance
GSMC participates with all Aetna plans, including Aetna HMO, and with many other insurance plans. Coverage for a specific procedure depends on your plan and may need prior authorization; call 732-202-3000 to verify. Our team can help check your benefits before treatment.
Book an appointment
One phone number for all 7 GSMC offices in Ocean and Monmouth County.
Our offices
- Whiting
- Toms River (1314 Hooper Ave)
- Brick
- Barnegat
- Manahawkin
- Freehold (322 Professional View Dr)
- West Long Branch
Telehealth visits are available for second opinions and imaging reviews only, by phone. Please call 732-202-3000 to book one.
This page is general patient education and does not replace advice from your own clinician. Individual results vary, and no outcome can be promised.