Tibial Nerve Stimulation For Overactive Bladder

The persistent urge to urinate, often accompanied by involuntary leakage, can significantly disrupt daily life, potentially indicating an overactive bladder (OAB). While various treatments exist, tibial nerve stimulation (TNS) offers a minimally invasive approach to regain bladder control.

Understanding Overactive Bladder (OAB)

Overactive bladder is a condition characterized by a sudden, uncontrollable urge to urinate. This urge may lead to incontinence, the involuntary loss of urine. OAB affects millions worldwide, impacting their social, emotional, and psychological well-being.

Symptoms of OAB include:

• Urgency: A sudden, compelling need to urinate that is difficult to defer.
• Frequency: Urinating more than eight times in a 24-hour period.
• Nocturia: Waking up two or more times during the night to urinate.
• Urge incontinence: Leakage of urine that occurs with a sudden urge to urinate.

Several factors can contribute to OAB, including:

• Nerve damage: Conditions like diabetes, multiple sclerosis, or stroke can disrupt nerve signals between the brain and bladder.
• Weakened pelvic floor muscles: Pregnancy, childbirth, and aging can weaken the muscles that support the bladder.
• Medications: Certain medications, such as diuretics, can increase urine production and exacerbate OAB symptoms.
• Excess weight: Obesity can put extra pressure on the bladder, leading to OAB.
• Unknown causes: In many cases, the exact cause of OAB remains unclear.

What is Tibial Nerve Stimulation (TNS)?

Tibial nerve stimulation (TNS), also known as percutaneous tibial nerve stimulation (PTNS), is a neuromodulation technique used to treat overactive bladder (OAB) and related urinary symptoms. It involves delivering gentle electrical pulses to the tibial nerve, located in the ankle, which indirectly modulates the neural pathways controlling bladder function. This modulation can help to calm the overactive bladder and reduce symptoms such as urinary frequency, urgency, and urge incontinence. TNS is a minimally invasive procedure that is typically administered in a series of outpatient sessions.

How Does Tibial Nerve Stimulation Work?

The precise mechanism of action of TNS is not fully understood, but it is believed to work by modulating the neural pathways that control bladder function. Here's a breakdown of the process:

1. Targeting the Tibial Nerve: The posterior tibial nerve is a mixed nerve (containing both sensory and motor fibers) that runs from the lower back down the leg and passes near the ankle. This nerve shares a common nerve pathway with the nerves that control the bladder and pelvic floor muscles.
2. Electrical Stimulation: During a TNS session, a small, thin needle electrode is inserted near the tibial nerve in the ankle. A surface electrode is placed on the foot to complete the circuit. A low-frequency electrical current is then passed through the needle electrode.
3. Neuromodulation: The electrical stimulation of the tibial nerve sends impulses that travel up the leg and along the sacral nerve plexus, which is a network of nerves in the lower back that innervates the bladder, pelvic floor muscles, and urinary sphincters.
4. Modulating Bladder Control: The electrical stimulation is thought to help "retrain" the nerves and muscles involved in bladder control. It may:
   • Reduce the involuntary contractions of the detrusor muscle (the bladder muscle), which cause the urge to urinate.
   • Increase the capacity of the bladder to hold urine.
   • Improve the coordination between the bladder and the brain, reducing the sensation of urgency.
5. Gradual Improvement: TNS typically requires a series of treatments over several weeks to achieve optimal results. Each session lasts about 30 minutes, and patients usually receive one treatment per week for 12 weeks, followed by maintenance sessions as needed.

While the exact mechanisms are still being researched, TNS is believed to improve bladder control by:

• Modulating nerve signals: TNS helps to regulate the nerve signals between the bladder and the brain, reducing the urge to urinate.
• Strengthening pelvic floor muscles: The electrical stimulation can also help to strengthen the pelvic floor muscles, which support the bladder and help to prevent leakage.
• Increasing bladder capacity: TNS may help to increase the amount of urine the bladder can hold, reducing the frequency of urination.

Who is a Good Candidate for Tibial Nerve Stimulation?

TNS is generally considered for individuals with OAB who:

• Have not found adequate relief from first-line treatments, such as lifestyle modifications (dietary changes, fluid management, bladder training) and medications (anticholinergics, beta-3 adrenergic agonists).
• Are unable to tolerate the side effects of medications.
• Are not candidates for more invasive surgical procedures.

TNS may be a suitable option for individuals experiencing:

• Urgency urinary incontinence (UUI): Involuntary leakage of urine accompanied by a strong urge to urinate.
• Urinary frequency: Needing to urinate more than eight times in a 24-hour period.
• Nocturia: Waking up two or more times during the night to urinate due to the need to void.
• Urge-predominant mixed urinary incontinence: A combination of urgency urinary incontinence and stress urinary incontinence (leakage due to physical exertion).

However, TNS may not be appropriate for individuals with certain conditions, including:

• Pregnancy: TNS is generally avoided during pregnancy due to the lack of safety data.
• Significant nerve damage: If the tibial nerve is severely damaged, TNS may not be effective.
• Pacemakers or implantable defibrillators: The electrical stimulation from TNS may interfere with the function of these devices.
• Skin infections or open wounds: The presence of infection or wounds near the ankle may increase the risk of complications.

A thorough evaluation by a qualified healthcare provider is necessary to determine if TNS is an appropriate treatment option. This evaluation may include a review of medical history, physical examination, bladder diary, and urodynamic testing to assess bladder function.

The Tibial Nerve Stimulation Procedure: Step-by-Step

The TNS procedure is typically performed in a doctor's office or clinic. Here's a step-by-step guide:

1. Preparation:
   • The patient is seated comfortably, and the lower leg and ankle are exposed.
   • The skin around the ankle is cleaned with an antiseptic solution.
2. Electrode Placement:
   • A thin needle electrode is inserted through the skin near the tibial nerve, typically located a few inches above the ankle bone (medial malleolus).
   • A surface electrode (a small, sticky pad) is placed on the inside of the foot to complete the electrical circuit.
3. Stimulation:
   • The needle electrode is connected to a TNS device, which generates a low-frequency electrical current.
   • The healthcare provider gradually increases the intensity of the electrical stimulation until the patient feels a tingling or tapping sensation in the foot or toes. The sensation should be noticeable but not painful.
4. Treatment Session:
   • The electrical stimulation is continued for approximately 30 minutes.
   • During the session, the patient may sit quietly, read, or watch television.
5. Completion:
   • After 30 minutes, the electrical stimulation is turned off.
   • The needle electrode is removed, and a bandage is applied to the insertion site.
   • The surface electrode is removed.
6. Post-Treatment:
   • Patients can typically resume their normal activities immediately after the TNS session.
   • A series of treatments is required to achieve optimal results. The typical treatment course involves 12 weekly sessions, followed by maintenance sessions as needed.

Benefits of Tibial Nerve Stimulation

TNS offers several potential benefits for individuals with OAB:

• Minimally Invasive: TNS is a non-surgical procedure that does not require any incisions or anesthesia.
• Effective: Studies have shown that TNS can significantly reduce OAB symptoms, such as urinary frequency, urgency, and urge incontinence.
• Safe: TNS is generally considered to be a safe procedure with minimal side effects.
• Well-Tolerated: Most patients tolerate TNS well, with minimal discomfort during the procedure.
• Improved Quality of Life: By reducing OAB symptoms, TNS can help to improve quality of life, allowing individuals to participate more fully in social and recreational activities.
• Reversible: TNS is a reversible treatment, meaning that the effects will gradually diminish if the treatment is stopped. This allows patients to try TNS without committing to a permanent solution.
• Few Side Effects: Compared to medications, TNS has fewer systemic side effects. Common side effects of OAB medications include dry mouth, constipation, and blurred vision.

Potential Risks and Side Effects

While TNS is generally considered safe, potential risks and side effects include:

• Pain or discomfort: Some patients may experience mild pain or discomfort at the needle insertion site.
• Skin irritation: The surface electrode may cause skin irritation or redness.
• Bleeding or bruising: There is a small risk of bleeding or bruising at the needle insertion site.
• Infection: Although rare, there is a risk of infection at the needle insertion site.
• Temporary changes in bowel function: Some patients may experience temporary changes in bowel function, such as constipation or diarrhea.
• Worsening of symptoms: In rare cases, TNS may temporarily worsen OAB symptoms.

It is important to discuss these potential risks and side effects with a healthcare provider before undergoing TNS.

What to Expect After Tibial Nerve Stimulation

Following a course of TNS treatments, individuals may experience a gradual improvement in their OAB symptoms. The extent of improvement can vary from person to person. Some individuals may experience a significant reduction in urinary frequency, urgency, and urge incontinence, while others may experience more modest improvements.

To maintain the benefits of TNS, maintenance sessions are typically required. The frequency of maintenance sessions will vary depending on the individual's response to treatment. Some individuals may only need occasional maintenance sessions, while others may require more frequent treatments.

It is important to continue to follow a healthy lifestyle, including maintaining a healthy weight, avoiding bladder irritants (such as caffeine and alcohol), and practicing pelvic floor exercises (Kegels).

TNS vs. Other OAB Treatments

TNS is one of several treatment options available for OAB. Other treatments include:

• Lifestyle modifications: Dietary changes, fluid management, and bladder training.
• Medications: Anticholinergics and beta-3 adrenergic agonists.
• Botulinum toxin (Botox) injections: Injections of Botox into the bladder muscle to relax it.
• Sacral neuromodulation: A more invasive procedure that involves implanting a device to stimulate the sacral nerves.
• Surgery: In rare cases, surgery may be necessary to correct underlying anatomical problems that are contributing to OAB.

TNS offers a unique approach compared to other treatments. Unlike medications, TNS has fewer systemic side effects. Compared to sacral neuromodulation, TNS is less invasive.

Here's a brief comparison:

The choice of treatment will depend on the individual's symptoms, medical history, and preferences. A healthcare provider can help determine the most appropriate treatment plan.

Scientific Evidence and Research

Numerous studies have investigated the effectiveness of TNS for treating OAB. A systematic review and meta-analysis published in the journal Neurology and Urodynamics found that TNS was significantly more effective than sham stimulation (placebo) for reducing urinary frequency, urgency, and urge incontinence.

Another study published in the Journal of Urology found that TNS was as effective as anticholinergic medications for treating OAB, but with fewer side effects.

These studies provide evidence that TNS is an effective and safe treatment option for OAB. However, more research is needed to determine the long-term effectiveness of TNS and to identify which individuals are most likely to benefit from the treatment.

Conclusion

Tibial nerve stimulation is a promising treatment option for individuals with overactive bladder who have not found relief from other therapies. This minimally invasive procedure offers a safe and effective way to modulate nerve signals, strengthen pelvic floor muscles, and increase bladder capacity. By understanding the process, benefits, and potential risks, individuals can make informed decisions about whether TNS is right for them, ultimately improving their quality of life and regaining control over their bladder function.