Percutaneous Electrical Nerve Stimulation (PENS)

Sciatica, caused by a herniated nucleus pulposus, is a common and painful condition that significantly impacts many individuals. It is often a result of pressure on the spinal nerves, which can lead to radiating pain, often down the leg. This condition affects an estimated 40% of the population over their lifetime. Traditional treatments, such as analgesic medications, provide only temporary relief and come with known side effects. Other common treatments, like epidural steroid injections, offer short-term improvement in leg pain but do not significantly improve overall functionality or reduce the need for surgery.

How Common It Is and Who Gets It? (Epidemiology)

Sciatica is prevalent in both men and women, with lifetime prevalence estimates suggesting that up to 40% of people will experience the condition at some point in their lives. The risk of developing sciatica increases with age, particularly between 30 to 50 years, and is often associated with degenerative conditions such as disc herniation and spinal stenosis. Occupations that involve heavy lifting, bending, or prolonged sitting may increase the risk, as do conditions like obesity and a sedentary lifestyle.

Why It Happens – Causes (Etiology and Pathophysiology)

Sciatica is primarily caused by the compression of the sciatic nerve, often due to a herniated disc, but it can also be triggered by spinal stenosis or other degenerative conditions of the spine. The herniation of a disc leads to the protrusion of its inner material, which puts pressure on the nerve root, causing pain, inflammation, and muscle weakness along the nerve’s path. In some cases, sciatica may be aggravated by factors like trauma or muscle spasms, further contributing to nerve compression.

How the Body Part Normally Works? (Relevant Anatomy)

The sciatic nerve is the largest nerve in the body, running from the lower back through the hips and buttocks, down each leg. The nerve is responsible for providing movement and sensation to parts of the lower leg, foot, and thigh. When the nerve is compressed, typically by a herniated disc, the flow of nerve impulses is disrupted, leading to pain, numbness, and weakness in the areas it serves.

What You Might Feel – Symptoms (Clinical Presentation)

Symptoms of sciatica include pain that radiates from the lower back or buttocks down the leg, often in the back or side of the leg. The pain may be sharp, burning, or shooting in nature and can worsen with certain movements, such as sitting or standing for prolonged periods. Patients may also experience numbness, tingling, or weakness in the affected leg, making it difficult to perform certain activities like walking or bending.

How Doctors Find the Problem? (Diagnosis and Imaging)

Diagnosis typically involves a thorough clinical examination and medical history review. Imaging tests like MRI or CT scans can confirm the presence of a herniated disc or other conditions causing nerve compression. An X-ray may also be used to rule out other potential causes, such as fractures or arthritis. In some cases, electromyography (EMG) or nerve conduction studies may be used to assess the function of the nerves and muscles.

Classification

Sciatica is generally classified based on its underlying cause, such as disc herniation, spinal stenosis, or degenerative disc disease. It is also categorized by severity, ranging from mild symptoms that resolve with conservative treatment to severe cases that may require surgical intervention.

Other Problems That Can Feel Similar (Differential Diagnosis)

Other conditions that can mimic the symptoms of sciatica include hip arthritis, piriformis syndrome, sacroiliac joint dysfunction, and vascular claudication. A thorough evaluation is necessary to distinguish between these conditions and ensure appropriate treatment.

Treatment Options

Non-Surgical Care

Non-surgical treatments for sciatica include physical therapy, anti-inflammatory medications, muscle relaxants, and epidural steroid injections. Heat or cold therapy may also help alleviate pain. Many patients respond well to a combination of rest, exercise, and medication.

Surgical Care

Surgery may be considered if conservative treatments fail to relieve symptoms, particularly if there is significant nerve compression or progressive neurological deficits. Common surgical procedures include discectomy (removal of a portion of the herniated disc), microdiscectomy, and in some cases, spinal fusion.

Introduction to PENS

Percutaneous Electrical Nerve Stimulation (PENS) is a minimally invasive procedure designed to relieve pain by stimulating the nerves that are causing discomfort. This therapy combines the beneficial aspects of both Transcutaneous Electrical Nerve Stimulation (TENS) and electroacupuncture, using acupuncture-like needles inserted into the soft tissue to target the peripheral sensory nerves at the dermatomal levels associated with the pathology.

How Does PENS Work?

In a typical PENS session, thin needles are inserted into the muscle or soft tissue near the affected nerve. These needles are connected to a low-voltage electrical generator that sends mild electrical impulses to stimulate the nerve. The stimulation interferes with the pain signals being sent to the brain, which helps to reduce the sensation of pain and improve functionality.

According to research, including a study by Ghoname et al., PENS has been shown to be more effective than TENS and exercise therapies in providing short-term pain relief and improving physical function in patients with long-term low back pain (LBP)​. The treatment has demonstrated particular success in reducing pain associated with conditions like sciatica that are related to degenerative disc disease.

Benefits of PENS for Sciatica

PENS therapy provides multiple advantages, especially for patients with sciatica, by:

Targeting the source of the pain: The placement of needles along the dermatomal level of the affected nerves ensures that the therapy directly addresses the source of irritation.

Non-pharmacologic: PENS offers a drug-free alternative for pain relief, which can be crucial for patients concerned about the side effects of long-term medication use.

Immediate and long-term relief: Studies have shown that PENS can provide immediate analgesic effects and, with repeated sessions, longer-lasting pain relief.

Improved physical function: By decreasing pain levels, PENS enables patients to engage in physical activities that they might otherwise avoid due to discomfort. This, in turn, can aid in rehabilitation efforts.

Comparing PENS with Other Treatments

Compared to TENS, which applies electrical stimulation through pads placed on the skin’s surface, PENS delivers electrical impulses directly into the muscle and nerve tissue, leading to a more targeted and effective treatment for certain conditions. The research has also indicated that patients receiving PENS therapy report better pain relief and enhanced quality of life compared to those receiving TENS or exercise therapy alone​

PENS therapy’s ability to reduce the need for oral analgesics is another significant benefit, as demonstrated by the reduction in daily non-opioid analgesic intake by patients undergoing PENS therapy​. This factor alone makes PENS an attractive option for individuals who wish to avoid the risks associated with long-term pain medication use.

What to Expect During a PENS Treatment

PENS treatments are typically short, lasting around 30 minutes per session. The procedure is generally well-tolerated, with many patients describing a mild tapping or tingling sensation during the electrical stimulation. Because the needles are thin and the electrical impulses are low in intensity, discomfort is minimal.

The number of sessions required varies depending on the severity of the condition and the individual’s response to treatment. In many cases, patients begin to notice improvements in pain levels and physical function after just a few sessions, although a full course of treatment may involve multiple weeks of therapy.

Is PENS Right for You?

PENS therapy is not suitable for everyone, but it is particularly effective for individuals with chronic low back pain, sciatica, or pain caused by degenerative disc disease. It is also an excellent option for patients who have not found relief through medications, physical therapy, or TENS treatments.

However, patients with certain medical conditions, such as those with pacemakers or bleeding disorders, should discuss the risks and benefits of PENS with their healthcare provider before proceeding with the treatment.

Recovery and What to Expect After Treatment

Recovery time varies based on the type of treatment and the severity of the condition. Most patients who undergo non-surgical treatments experience relief within a few weeks. For those who undergo surgery, recovery may take several months, with rehabilitation focused on restoring strength and mobility. Post-treatment pain relief and physical therapy are essential for long-term recovery.

Possible Risks or Side Effects (Complications)

While PENS is generally well-tolerated, some patients may experience mild soreness at the needle insertion sites, as well as temporary changes in pain intensity. More severe complications are rare, but in any invasive treatment, there is a risk of infection, bleeding, or nerve injury. As with any therapy, patient suitability should be evaluated carefully.

Long-Term Outlook (Prognosis)

The prognosis for sciatica depends on the underlying cause and the effectiveness of the treatment. Many patients experience significant improvement with non-surgical treatments, although some may continue to have periodic flare-ups. In severe cases, surgery may offer long-term relief, but there may be ongoing restrictions in activities due to nerve damage or degeneration.

Out-of-Pocket Cost

Medicare

CPT Code 64555 – Percutaneous Electrical Nerve Stimulation (PENS): $474.99

Under Medicare, 80% of the approved cost for this procedure is covered once your annual deductible has been met. The remaining 20% is typically the patient’s responsibility. Supplemental insurance plans—such as Medigap, AARP, or Blue Cross Blue Shield—generally cover this 20%, leaving most patients with little to no out-of-pocket expenses for Medicare-approved procedures like PENS. These supplemental plans work directly with Medicare to provide full coverage for the procedure.

If you have secondary insurance—such as Employer-Based coverage, TRICARE, or Veterans Health Administration (VHA)—it functions as a secondary payer once Medicare processes the claim. After your deductible is satisfied, these secondary plans may cover any remaining balance, including coinsurance or any uncovered charges. Secondary plans typically have a modest deductible, usually between $100 and $300, depending on the specific policy and network status.

Workers’ Compensation
If your condition requiring PENS therapy is work-related, Workers’ Compensation will fully cover all treatment-related costs, including the procedure and rehabilitation. You will have no out-of-pocket expenses under an accepted Workers’ Compensation claim.

No-Fault Insurance
If your condition requiring PENS therapy is the result of a motor vehicle accident, No-Fault Insurance will cover the full cost of the procedure. The only possible out-of-pocket expense may be a small deductible depending on your individual policy terms.

Example
Emily, a 58-year-old patient with chronic back pain, underwent Percutaneous Electrical Nerve Stimulation (CPT 64555) for pain relief. Her estimated Medicare out-of-pocket cost was $474.99. Since Emily had supplemental insurance through AARP Medigap, the 20% that Medicare did not cover was fully paid, leaving her with no out-of-pocket expenses for the procedure.

Frequently Asked Questions (FAQ)

Q. How many PENS sessions will I need?
A. The number of sessions varies by individual and severity of the condition, but many patients experience improvement after 3-5 sessions.

Q. Is PENS therapy painful?
A. Most patients report only mild discomfort during PENS therapy, described as a mild tapping or tingling sensation.

Q. Can PENS replace surgery for sciatica?
A. PENS therapy is effective for many patients, but it is not a replacement for surgery in severe cases of sciatica with significant nerve compression or other complications.

Summary and Takeaway

Sciatica caused by a herniated disc can significantly impact daily life, but minimally invasive treatments like PENS offer a promising alternative to surgery and long-term medication use. By targeting the nerves directly and providing both immediate and long-term pain relief, PENS can improve quality of life for many individuals suffering from this debilitating condition.

Clinical Insight & Recent Findings

A recent study explored the effectiveness of Percutaneous Electrical Nerve Stimulation (PENS) for neuropathic pain, including sciatica. The systematic review and meta-analysis found that PENS significantly reduced pain intensity, improved sleep quality, decreased daily analgesic intake, and alleviated symptoms of depression.

Compared to sham stimulation, PENS was particularly effective in managing conditions like sciatica, diabetic neuropathy, and post-amputation pain.

The therapy’s efficacy in pain relief and its ability to improve physical and mental health parameters, with minimal side effects, highlights its potential as a valuable non-pharmacologic treatment option. (“Study of PENS for neuropathic pain – See PubMed.“)

Who Performs This Treatment? (Specialists and Team Involved)

PENS therapy is typically performed by trained physical therapists, pain management specialists, or other healthcare providers experienced in minimally invasive techniques. In some cases, the procedure may be performed by a physician specializing in pain management or rehabilitation.

When to See a Specialist?

Patients experiencing chronic or severe sciatica that does not respond to conservative treatments should consult a specialist to explore advanced options like PENS therapy or surgery.

When to Go to the Emergency Room?

Emergency medical care should be sought if sciatica symptoms are accompanied by severe leg weakness, loss of bowel or bladder control, or other neurological deficits, as these may indicate a more serious underlying condition.

What Recovery Really Looks Like?

Recovery from sciatica varies based on treatment. Non-surgical treatments generally lead to a quicker recovery, while surgery may require several weeks to months of rehabilitation. After PENS therapy, patients can typically resume normal activities, though they may need to avoid strenuous activities initially.

What Happens If You Ignore It?

If sciatica is left untreated, the pain may worsen, leading to chronic discomfort and functional limitations. In severe cases, untreated sciatica can result in permanent nerve damage, which may affect mobility and overall quality of life.

How to Prevent It?

Prevention of sciatica includes maintaining a healthy weight, engaging in regular exercise, practicing good posture, and avoiding prolonged sitting. Strengthening the core muscles and using proper lifting techniques can also reduce the risk of developing sciatica.

Nutrition and Bone or Joint Health

A balanced diet rich in calcium, vitamin D, and omega-3 fatty acids can support bone and joint health, potentially reducing the risk of conditions that lead to sciatica. Staying hydrated and avoiding smoking are also important for maintaining overall spinal health.

Activity and Lifestyle Modifications

Maintaining an active lifestyle is key to preventing sciatica and improving overall spinal health. Regular stretching, strengthening exercises, and low-impact activities like walking or swimming can improve flexibility and reduce the likelihood of nerve compression.

Do you have more questions?