Percutaneous tibial nerve stimulation (PTNS), also referred to as posterior tibial nerve stimulation, is the least invasive form of

neuromodulation Neuromodulation is the physiological process by which a given neuron uses one or more chemicals to regulate diverse populations of neurons. Neuromodulators typically bind to metabotropic, G-protein coupled receptors (GPCRs) to initiate a sec ...

used to treat

overactive bladder Overactive bladder (OAB) is a common condition where there is a frequent feeling of needing to urinate to a degree that it negatively affects a person's life. The frequent need to urinate may occur during the day, at night, or both. Loss of bl ...

(OAB) and the associated symptoms of urinary urgency, urinary frequency and urge incontinence. These urinary symptoms may also occur with

interstitial cystitis Interstitial cystitis (IC), a type of bladder pain syndrome (BPS), is chronic pain in the Urinary bladder, bladder and pelvic floor of unknown cause. Symptoms include urinary urgency, feeling the need to urinate right away, urinary frequency, ...

and following a radical

prostatectomy Prostatectomy (from the Ancient Greek language, Greek , "prostate" and , "excision") is the surgical removal of all or part of the prostate gland. This operation is done for benignity, benign conditions that cause urinary retention, as well as ...

. Outside the United States, PTNS is also used to treat

fecal incontinence Fecal incontinence (FI), or in some forms, encopresis, is a lack of control over defecation, leading to involuntary loss of bowel contents—including flatus (gas), liquid stool elements and mucus, or solid feces. FI is a sign or a symptom ...

. PTNS can be used as a primary therapy. Treatment for overactive bladder and fecal incontinence may begin with pharmacological therapies before PTNS is administered. Unlike the variety of OAB drugs available PTNS is more effective and produces far fewer side-effects. Nearly 80% of patients discontinue use (mean of 4.8 months) of drugs within the first year with as high as 17% of discontinuation being due to adverse side-effects. Neuromodulation is emerging as an effective modality to treat patients who are not successful with conservative methods and its demonstrated efficacy has been the topic of multiple publications.

Medical uses

Urinary incontinence

PTNS appears to be effective at improving the number of times a person who has overactive bladder syndrome needs to urinate, although the mechanism for this is unclear. It appears to work as well as medication, but with fewer side effects.

Fecal incontinence

A meta-review that considered mostly low quality studies found tentative evidence of a benefit for PTNS in

. However, a more recent high quality study however did not identify a benefit.

Procedure

A patient sits comfortably with the treatment leg elevated. A fine needle electrode is inserted into the lower, inner aspect of the leg, slightly cephalad/rostral to the

medial malleolus A malleolus is the bony prominence on each side of the human ankle. Each leg is supported by two bones, the tibia on the inner side (medial) of the leg and the fibula on the outer side (lateral) of the leg. The medial malleolus is the promin ...

. As the goal is to send stimulation through the tibial nerve, it is important to have the needle electrode near (but not on) the

tibial nerve The tibial nerve is a branch of the sciatic nerve. The tibial nerve passes through the popliteal fossa to pass below the arch of soleus. Structure Popliteal fossa The tibial nerve is the larger terminal branch of the sciatic nerve with root val ...

. A surface electrode (grounding pad) is placed over the medial aspect of the

calcaneus In humans and many other primates, the calcaneus (; from the Latin ''calcaneus'' or ''calcaneum'', meaning heel; : calcanei or calcanea) or heel bone is a bone of the Tarsus (skeleton), tarsus of the foot which constitutes the heel. In some other ...

on the same leg. The needle electrode is then connected to an external pulse generator which delivers an adjustable electrical pulse that travels to the

sacral plexus In human anatomy, the sacral plexus is a nerve plexus which provides motor and sensory nerves for the posterior thigh, most of the lower leg and foot, and part of the pelvis. It is part of the lumbosacral plexus and emerges from the lumbar verteb ...

via the tibial nerve. Among other functions, the sacral nerve plexus regulates

bladder The bladder () is a hollow organ in humans and other vertebrates that stores urine from the kidneys. In placental mammals, urine enters the bladder via the ureters and exits via the urethra during urination. In humans, the bladder is a distens ...

and

pelvic floor The pelvic floor or pelvic diaphragm is an anatomical location in the human body which has an important role in urinary and anal continence, sexual function, and support of the pelvic organs. The pelvic floor includes muscles, both skeletal and ...

function. With correct placement of the needle electrode and level of electrical impulse, there is often an involuntary toe flex or fan, or an extension of the entire foot. However, for some patients, the correct placement and stimulation may only result in a mild sensation in the ankle area or across the sole of the foot. The treatment protocol requires once-a-week treatments for 12 weeks, 30 minutes per session. Many patients begin to see improvements by the 6th treatment. Patients who respond to treatment may require occasional treatments (about once every three weeks or as needed) to sustain improvements. PTNS is a low-risk procedure. The most common side-effects with PTNS treatment are temporary and minor, resulting from the placement of the needle electrode. They include minor bleeding, mild pain and skin inflammation.

Research and market approval

The methodology was first invented by Marshall Stoller at

UCSF Medical Center The UCSF Medical Center is a research and teaching hospital in San Francisco, California, and is a medical center of the University of California, San Francisco. It is affiliated with the UCSF School of Medicine and the UCSF Helen Diller Famil ...

, San Francisco, and was first known as the SANS (Stoller Afferent Nerve Stimulator) protocol. In 2000, Stoller reported that 98 patients were treated with the SANS device with an approximate 80% success rate in treating urge incontinence syndrome, including urgency and frequency. In a corroborative multi-center study by Govier, et al., 71% of patients achieved success. Additionally, in a study by Shafik, et al., 78% of patients achieved a long-term improvement in faecal incontinence when treated with PTNS. Regulatory clearances were based on these data. A PTNS device received FDA-clearance for urinary urgency, urinary frequency and urge incontinence in 2000; in 2010, the clearance was updated to include overactive bladder (OAB). A PTNS device received the CE mark for urinary urgency, urinary frequency and urge incontinence and fecal incontinence in 2005. Since 2005, Uroplasty has marketed the Urgent PC Neuromodulation System. In 2015, Medtronic acquired Advanced Uro-Solutions for its PTNS therapy, and began marketing the NURO PTNM System in 2016.

U.S. reimbursement

Effective January 1, 2011, the PTNS procedure will be billed under the new CPT code 64566, with the descriptor "Posterior tibial neurostimulation, percutaneous needle electrode, single treatment, includes programming."

U.K. NICE guidance

In October 2010, the

National Institute for Clinical Excellence National may refer to: Common uses * Nation or country ** Nationality – a ''national'' is a person who is subject to a nation, regardless of whether the person has full rights as a citizen Places in the United States * National, Maryland, ce ...

(NICE) issued NICE Interventional Procedure Guidance 362 supporting the use of percutaneous tibial nerve stimulation (PTNS) as a routine treatment for overactive bladder syndrome. Highlights of the NICE guidance include: Evidence shows that PTNS is effective in reducing symptoms in the short and medium term. There are no major safety concerns. It can be offered routinely as a treatment option for people with overactive bladder provided that doctors are sure that the patients understand what is involved and agree to the treatment and that the results of the procedure are monitored. A NICE guidance for fecal incontinence is currently under review.

Transcutaneous tibial nerve stimulation

Recent studies have been carried out to demonstrate the efficacy of transcutaneous tibial nerve stimulation with the use of external electrodes. Electrodes are applied near to the ankle where the tibial/sural nerve is located. It is believed that the electrical stimulation can penetrate the skin delivering tibial nerve stimulation in the same way, but without the need for a needle electrode. It is thought that further studies on alternative possible treatments, such as home based transcutaneous stimulation, are needed. However, it has proved a viable and successful treatment for many.

References

External links

National Association for Continence – PTNS overview

Commercial production of PTNS
{{DEFAULTSORT:Percutaneous Tibial Nerve Stimulation Urologic procedures