Electrical Stimulation for Pelvic Floor Muscle Weakness

Hi, Bestie! Today, we’re talking about electrical stimulation (e-stim) and how it can be used to improve pelvic floor muscle (PFM) strength. We’ve done a bunch of chatting about transcutaneous electrical nerve stimulation (TENS) units in the past. A TENS unit produces an electrical current and is used as a form of e-stim. However, we’re moving away from the TENS unit today and discussing some other types of e-stim. Let’s start with a bit of review.  

What is e-stim?

E-stim is a type of noninvasive treatment that uses electrical impulses to target specific tissues. There are many types of e-stim including high voltage e-stim, neuromuscular e-stim (NMES), functional e-stim (FES), interferential current (IFC) and TENS. Each form of e-stim utilizes different types of currents and/or settings and is best suited to a certain purpose. For example, IFC is best suited to managing pain, while NMES and FES are used for improving muscle function. When used appropriately, e-stim can be a super useful tool in the rehabilitation process.

How can estim help with pfm weakness and urinary incontinence?

It has been pretty well documented that certain types of e-stim can have a positive impact on PFM strength (1, 2, 3, 4). However, it is a lot more nuanced than that! E-stim has been shown to improve PFM strength in folks that have extremely weak PFMs. Let’s review how PFM strength is graded. Strength is given a grade from 0 to 5. Grade 0 indicates no muscle activity; grade 1 indicates a “flicker” of muscle activity; grade 2 corresponds to weak muscle activity with no PFM “lift;” grade 3 is a muscle contraction with PFM “squeeze & lift;” grade 4 indicates good muscle contraction with “squeeze & lift” and ability to hold against some resistance; grade 5 is a strong muscle contraction with squeeze, lift, and ability to maintain position against resistance. Generally, e-stim for PFM strengthening is beneficial in those with PFM strength of grades 0 or 1.

Let’s take a look at the research. A 2013 study by Correia et. al. looked at the effect of intravaginal e-stim on stress urinary incontinence (SUI) in females. In this study, researchers utilized an FES current. FES, or functional e-stim, utilizes an electrical charge to stimulate a muscle or group of muscles to contract. In other words, it helps the muscle to perform its normal activity. In folks with grade 0 or grade 1 PFM strength, the PFMs are not contracting the way they should. This study tested FES to see if it could help very weak PFMs to perform better in order to reduce the severity of urinary incontinence. Participants underwent 12 sessions of e-stim and the study found that folks had significantly less SUI after treatment was completed (3).

Other studies reported similar findings. A 2013 study by Chêne et. al., a 2019 study by Rodrigues et. al., and a 2021 study by Antônio et. al. all reported increased PFM strength to at least 2 (out of 5) and/or reduced urinary symptoms. Note that each study utilized its own treatment parameters. No two studies were identical in the amount of time patients spent using the e-stim machines and studies didn’t use the exact same e-stim settings, either. Subjects had as few as 6 sessions on e-stim and as many as 50. It is important to understand that there is no set of parameters that is “best” or “right.” You and your therapist may need to play around with parameters a bit before finding what works best for you and your symptoms.  The general e-stim settings used in the research were as follows: Frequency (50Hz); Pulse Width (200-300 microseconds); Treatment Time (20 minutes); and On/Off Time (5 seconds on, 10 seconds off). Intensity was set to the maximum amount the subject could tolerate and the goal was for the e-stim to instigate a muscle contraction. In about half of the studies, participants were encouraged to try contracting the PFMs during the “on” cycle of e-stim.

Intravaginal Electrode

Note that each of these studies looked at intravaginal e-stim. This means a vaginal electrode was inserted into the vaginal canal and connected to the e-stim machine via a wire. This is still considered to be a non-invasive technique since it doesn’t break the skin barrier. However, it is important to note that with intravaginal electrodes, each patient must have their own, unique electrode (I hope this is obvious). I mention this because these electrodes can be expensive! While the sticky electrode pads that can be placed on the skin are relatively cheap, a single, vaginal electrode can run upwards of $50.00. The good news is that vaginal electrodes are a bit sturdier than traditional electrode pads and can be used indefinitely, as long as they are regularly cleaned and cared for.

Remember: there are precautions and contraindications when it comes to using electrical devices. If you are pregnant, have a pacemaker, epilepsy, or altered skin sensation, e-stim may not be safe for you to use. Always check with your physician before initiating use of this type of electrical device. Your therapist should discuss your medical history with you prior to starting you on e-stim treatment.

For folks that are having a tough time contracting or “finding” their PFMs, intravaginal e-stim can be a great tool. If you already know how to contract your PFMs, but still experience urinary incontinence, there are tons of other treatment options that will serve you better (see biofeedback and pelvic floor muscle training (PFMT)).

Let’s catch up soon.

XOXO,

Your Pelvic Bestie

References:

1.     Antônio FI, Bø K, Pena CC, et al. Intravaginal electrical stimulation increases voluntarily pelvic floor muscle contractions in women who are unable to voluntarily contract their pelvic floor muscles: a randomised trial. Journal of Physiotherapy. doi:10.1016/j.jphys.2021.12.004

2.     Rodrigues MP, Barbosa LJF, Paiva LL, Mallmann S, Sanches PRS, Ferreira CF, Ramos JGL. Effect of intravaginal vibratory versus electric stimulation on the pelvic floor muscles: A randomized clinical trial. Eur J Obstet Gynecol Reprod Biol X. 2019 May 12;3:100022. doi: 10.1016/j.eurox.2019.100022. PMID: 31403114; PMCID: PMC6687376.

3.     Correia GN, Pereira VS, Hirakawa HS, Driusso P. Effects of surface and intravaginal electrical stimulation in the treatment of women with stress urinary incontinence: randomized controlled trial. Eur J Obstet Gynecol Reprod Biol . 2014;173:113-8. doi: 10.1016/j.ejogrb.2013.11.023. Epub 2013 Dec 4.

4.     Chêne G, Mansoor A, Jacquetin B, Mellier G, Douvier S, Sergent F, Aubard Y, Seffert P. Female urinary incontinence and intravaginal electrical stimulation: an observational prospective study. Eur J Obstet Gynecol Reprod Biol. 2013 Sep;170(1):275-80. doi: 10.1016/j.ejogrb.2013.06.011. Epub 2013 Jul 5. PMID: 23830965.

*The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a qualified health provider regarding any questions you may have about a medical condition or health objectives