Musculoskeletal Health

If you saw the Washington Post headline saying retatrutide may also ease knee pain, here is the short answer. In two large phase 3 trials, adults with painful knee osteoarthritis and obesity who took retatrutide reported bigger drops in pain than those who took a placebo, and they also lost more weight. The results were published online ahead of print on 2026-11-08 in the New England Journal of Medicine paper. Retatrutide is investigational and not yet FDA approved, and Eli Lilly supported both trials. The trials also recorded side effects that were common, mostly nausea, diarrhea and vomiting, so weigh them with your clinician before you decide anything.

Affiliate disclosure: Note that you will find affiliate links on this page. The editors may earn a commission if you buy through them. It does not add to the price you pay.

Quick facts, as of 2026-11-11

What did the two NEJM trials test?

TRIUMPH-4 and TRIUMPH-1-OA each randomized adults to once-weekly subcutaneous (under-the-skin) retatrutide or placebo. Both enrolled adults without diabetes who had painful knee osteoarthritis and a BMI of at least 27. The group sizes for TRIUMPH-4 come from the American College of Rheumatology abstract, which lists 445 randomized.

TRIUMPH-1-OA is the knee arm of the TRIUMPH-1 weight trial. Eli Lilly’s Eli Lilly TRIUMPH-1 release, dated 2026-06-06, says the trial started people at 2 mg and stepped the dose up every four weeks. The TRIUMPH trial design paper on PubMed describes the program as a basket of weight, sleep apnea and knee osteoarthritis studies.

How much did knee pain drop?

The WOMAC pain score runs from 0 to 10, and higher scores mean worse pain. The trials report results under different counting methods, called estimands. Compare only numbers that use the same estimand.

The difference from placebo is the number that compares the drug with the sugar-pill group, so it is the one to read first. The NEJM abstract reports these differences from placebo, with 95% confidence intervals in brackets:

In TRIUMPH-1-OA, the hybrid-treatment pain changes at week 80 were -3.22 (4 mg), -3.48 (9 mg) and -3.64 (12 mg), against -1.87 on placebo. Lilly’s June 2026 release on TRIUMPH-1 says WOMAC pain fell by up to 4.3 points (73.1%) from a baseline of 6.0. The American College of Rheumatology abstract calls the TRIUMPH-4 improvements “clinically meaningful.”

Lilly reports that, on the efficacy estimand, at least a 70% pain reduction was reached by 73.0% of people on 9 mg, 67.7% on 12 mg and 26.2% on placebo. The placebo groups improved too, with pain drops of 1.87 to 2.43 points across the trials.

How does retatrutide help knee osteoarthritis?

The NEJM abstract concludes that retatrutide produced significantly greater reductions in both the WOMAC pain score and body weight than placebo, in people with painful knee osteoarthritis and obesity. The trial results show pain and weight falling together on retatrutide, so that is what the numbers in this article report. The abstract describes retatrutide as an investigational triple agonist of the GIP, GLP-1 and glucagon receptors, and the NEJM abstract on PubMed carries the full summary of the design.

How much weight did people lose?

Eli Lilly’s headline, “weight loss of up to an average of 71.2 lbs,” is the efficacy estimand for the 12 mg group (32.3 kg). The NEJM figure for the same group is -23.7% under the treatment-regimen counting, which is why the two numbers look different. In TRIUMPH-1, Lilly reports average losses of 64.4 lbs (25.9%) on 9 mg, 70.3 lbs (28.3%) on 12 mg and 47.2 lbs (19.0%) on 4 mg. In the 104-week extension of 12 mg, among 532 people with a BMI of at least 35, average loss was 85.0 lbs (30.3%).

What are the side effects?

The NEJM abstract says serious adverse events were more common with retatrutide than with placebo, and that gastrointestinal events were the most common. The tables below are Eli Lilly’s figures, from its Eli Lilly TRIUMPH-4 release (2025-12-11) and its TRIUMPH-1 release (2026-06-06).

Dysesthesia is Lilly’s term for abnormal skin sensation. In TRIUMPH-4, Lilly reports stopping because of side effects at 8.8% on 9 mg, 12.1% on 12 mg and 4.8% on placebo among people with a baseline BMI of at least 35. Lilly says overall discontinuation was similar across arms. Higher doses had the higher rates of stopping because of side effects in both trials.

Who were the trials for?

• Adults without diabetes.
• Adults with painful knee osteoarthritis and a BMI of at least 27. The NEJM title describes them as adults with knee osteoarthritis pain and obesity.
• In TRIUMPH-4, participants had WOMAC pain between 4 and 9 on the 0 to 10 scale at entry (ACR abstract).
• TRIUMPH-4 participants had an average baseline weight of 112.7 kg (248.5 lbs) and a BMI of 40.4 (Eli Lilly release, 2025-12-11).

Eli Lilly, the maker, sponsored the studies. The trials were about the knee and about weight, and they were run in adults without diabetes.

What is knee osteoarthritis?

The NIAMS osteoarthritis overview from the U.S. National Institute of Arthritis and Musculoskeletal and Skin Diseases describes osteoarthritis as a degenerative joint disease, in which the tissues in the joint break down over time. It is the most common type of arthritis and is more common in older people. The knee is one of the most commonly affected joints. The NIAMS overview says osteoarthritis affects each person differently.

What causes knee osteoarthritis, and is it hereditary?

NIAMS says researchers do not know what triggers or starts the breakdown of joint tissue. It also says osteoarthritis does not happen because of simple wear and tear. Factors that can make it more likely include:

• Aging.
• Being overweight or obese.
• A history of injury or surgery to a joint.
• Overuse from repetitive movements of the joint.
• Joints that do not form correctly.
• A family history of osteoarthritis.

So family history is one factor, not the whole story. NIAMS notes that younger people can also develop osteoarthritis, usually from joint injury, abnormal joint structure or a genetic defect in joint cartilage.

Is knee osteoarthritis serious?

It depends on the person. NIAMS says it is relatively mild for some people and does not affect day-to-day activities. For others, it causes significant pain and disability. Joint damage usually develops gradually over years, although it can worsen quickly in some people. As symptoms progress, things like stepping up, getting on and off the toilet, getting in and out of a chair and walking across a parking lot can become difficult. NIAMS also notes that pain and other symptoms can leave you tired, affect sleep and lead to depression.

What are the first signs of knee osteoarthritis?

NIAMS says symptoms often start slowly, usually in one or a few joints. Watch for these:

• Pain when you use the knee, which may improve with rest.
• Stiffness, usually lasting less than 30 minutes, in the morning or after a period of rest.
• Swelling in and around the knee, especially after a lot of activity.
• A grinding or scraping noise when you walk or move.
• Over time, muscle and ligament weakness that can make the knee buckle.
• A feeling that the knee is loose or unstable.

A simple log of when the pain starts, how long the stiffness lasts and what you were doing can give your clinician useful detail.

Can knee osteoarthritis be reversed or cured?

NIAMS describes the breakdown as usually gradual, over years. The retatrutide trials measured pain and weight, not cartilage, so they say nothing about whether the joint itself heals. Ask your doctor what goal fits your knee.

How do people manage knee osteoarthritis now?

The options worth discussing depend on your symptoms, your weight and your health history. Your doctor or physical therapist can walk you through the current choices and which fit your knee. If you want to compare other approaches people try for knee pain, our magnesium cream for knee pain guide and our molecular hydrogen for joint pain guide each set out the research on that approach.

Common mix-ups

• Trial results are not approval. Retatrutide is not yet FDA approved, according to the Washington Post column description dated 2026-11-11, and Lilly calls it investigational.
• Pain and weight were both measured. Pain and weight fell together on retatrutide, and both were primary measures in TRIUMPH-4.
• Different numbers, same trial. Headline weight figures and NEJM weight figures use different estimands. Always name the estimand.
• Trade-outlet figures. The HCPLive TRIUMPH-1 knee report (2026-09-29) gives week 80 WOMAC changes of -3.2, -3.5 and -3.6 across doses against -1.9 on placebo. HCPLive’s numbers come from a different analysis than the NEJM abstract.
• Placebo also improved. Placebo groups recorded pain drops of 1.87 to 2.43 points.
• Arthritis is a broad word. Knee osteoarthritis is one type. NIAMS calls osteoarthritis the most common type of arthritis.
• Osteoarthritis and a meniscus tear. NIAMS lists the meniscus among knee tissues that osteoarthritis can damage. Telling the two apart is a question for your doctor.

Before you decide anything

1. Ask your doctor or physical therapist which current knee osteoarthritis options fit your pain, weight and health history.
2. Ask how your knee symptoms are diagnosed and whether they fit knee osteoarthritis.
3. Ask whether knee osteoarthritis could explain pain in your hip, calf, ankle, shin or thigh, or numbness and tingling.
4. If retatrutide comes up, ask your prescriber what investigational status means for you and which side effects matter most with your health history.
5. Ask your prescriber or Eli Lilly for current access and cost details, since these change.
6. Read the NEJM abstract on PubMed with your clinician before you decide.

By BackToHealthTroy.com Editorial Team

Vagus nerve stimulation for fibromyalgia has been studied, but the work is early. The two pilots this page covers are uncontrolled: Lange’s 2011 pilot of 14 people with implanted devices, and Dolcini’s 2025 pilot of 18 people using ear-based stimulation. Neither compared stimulation with a sham (fake stimulation) group, and a 2025 systematic review by Perin and colleagues says small samples and differing sham definitions and parameters “limit current interpretability.” Below you will find what each study found, what the FDA has and has not approved, and what to ask before you consider a device.

For wider context on where this research sits, see our complete guide to vagus nerve research in chronic pain conditions like fibromyalgia.

Affiliate disclosure: Note that you will find affiliate links on this page. The editors may earn a commission if you buy through them. It does not add to the price you pay.

Quick facts (2026-11-11)

Can a vagus nerve stimulator help with fibromyalgia?

The two pilots report improvements in pain and related symptoms in the people they studied. Each result belongs to the device and group in its own study. It does not carry over to other devices, to other conditions, or to products sold to consumers.

What the studies found, in date order

Lange 2011: implanted stimulator in 14 people

Lange and colleagues published an open-label phase I/II trial in Pain Medicine. You can read the Lange 2011 pilot trial in full.

• Device: a surgically implanted vagus nerve stimulator, not a wearable.
• Who: 14 people with treatment-resistant fibromyalgia.
• Comparison: none. The authors call it an uncontrolled pilot study.
• Length: 3 months of stimulation, with follow-up visits at 5, 8 and 11 months.
• Results: 12 people completed the first 3 months. At 3 months, 5 people met the composite criteria for pain, overall wellness and physical function. Two of those 5 no longer met the widespread pain or tenderness criteria for fibromyalgia. More people met the criteria at 11 months.
• Side effects: similar to those seen with implanted VNS for epilepsy and depression, plus dry mouth and fatigue. Two people did not tolerate stimulation.
• Authors’ words: VNS “may be a useful adjunct treatment” for resistant fibromyalgia, but “further research is required.”

Dolcini 2025: ear-based stimulation in 18 people

Dolcini and colleagues titled their paper “Vagal nerve stimulation and fibromyalgia: an additional therapeutic option,” published in Clinical and Experimental Rheumatology on 27 June 2025. The Dolcini 2025 pilot study abstract is on PubMed.

• Device: auricular vagal neuromodulation therapy (AVNT), a non-invasive, ear-based therapy.
• Who: 18 people with fibromyalgia.
• Comparison: a single group. The abstract describes no control arm.
• Length: 4 weeks.
• Results: the widespread pain index fell at week 2 (p = 0.03) and at week 4 (p = 0.004). At week 4, the revised FIQ total (p = 0.02), general health (p = 0.002), symptoms (p < 0.001) and sleep (PSQI, p = 0.02) improved. Serum BDNF did not change significantly.

Pellow 2025: review of non-invasive vagus stimulation for chronic pain

Pellow and colleagues reviewed randomized trials published from 2010 to 2023 in the Scandinavian Journal of Pain. The Pellow 2025 systematic review is on PubMed.

• Who: 1,474 records were found and 10 articles were included, with 813 participants in total: 763 on non-invasive vagus nerve stimulation (nVNS) and 50 on heart rate variability biofeedback.
• Fibromyalgia part: of the 9 nVNS studies, 2 studied fibromyalgia symptoms (138 people). Six studied headache or migraine (603 people) and 1 studied chronic low back pain (22 people). The headache results belong to headache.
• Outcomes across the nVNS studies: 3 reported significant results for episode frequency, 6 for pain intensity and 3 for medication use.
• Authors’ conclusion: they rate the evidence that nVNS reduces headache frequency as moderate to high quality, and say it is well tolerated. For chronic pain conditions, they wrote that “insufficient literature exists to support either approach.”

Perin 2025: systematic review of VNS and fibromyalgia

Perin and colleagues published a systematic review in Journal of Functional Morphology and Kinesiology on 29 December 2025. They searched on 24 October 2025.

• Included: 6 studies on VNS effects, 4 clinical studies and 2 protocols. A protocol is a study plan, not a result.
• Reported: the review’s abstract reports “improvements in pain, fatigue, sleep disturbance and autonomic regulation.”

Registered fibromyalgia trials, by start date

• Kasr El Aini Hospital (Egypt): study start 30 September 2023; status completed; estimated completion 15 March 2025. Women aged 18 to 55 were listed, with 87 total participants. Three arms: non-invasive vagus stimulation alone, stimulation plus medical treatment, and medical treatment alone.
• Massachusetts General Hospital: study start 1 July 2024; status active, recruiting; estimated completion 31 October 2029. 60 participants in two groups of 30, with pain intensity as the primary outcome and fatigue, sleep and health-related quality of life as secondary outcomes. Eligibility asked for a pain score of 4 or above on a 0 to 10 scale. The listing was updated 10 September 2026.
• Hasan Kalyoncu University (Turkey): first posted 26 October 2026; status not yet recruiting; estimated start 2 November 2026. This is a randomized, sham-controlled study adding non-invasive vagus stimulation to manual therapy in women with fibromyalgia, with pain, autonomic function and illness perception as outcomes. The ClinicalTrials.gov record NCT07894588 shows no results posted.

What the findings do not show

• The two pilots covered here are uncontrolled and compare nothing against a sham. The only registered sham-controlled trial in this group is not yet recruiting.
• Results from headache studies, TENS trials, and implanted epilepsy, depression or stroke devices belong to those uses. They do not describe fibromyalgia.
• A protocol describes a plan for a study. It is not a finding.

Approved, cleared or wellness: what the words mean

These terms are often mixed up. The FDA page explains the first three in its own words, and the makers describe the rest on their own pages.

Which vagus devices have FDA records, and for what

Consumer vagus devices and what their makers say

Several consumer devices are sold with vagus nerve language. Their makers describe them for stress, relaxation and general wellbeing. Truvaga says its devices support “a balanced nervous system.” Apollo Neuro says its wearable is intended to help manage stress, challenging life transitions and to promote a healthy lifestyle, and it describes vibration rather than electrical current. Pulsetto calls its neckband a general wellness device and says it does not claim to diagnose, treat, cure or prevent any condition. Nuropod, an ear device, says it is “scientifically proven to modulate the vagus nerve,” and its page lists “Third party certified device.” These are the makers’ own statements.

Side effects and who should avoid each option

Cleveland Clinic’s vagus nerve stimulation overview covers the implanted device. The table lists what each source reports.

Is nerve pain the same as muscle pain?

Pain is often sorted into two groups. Nerve pain, called neuropathic pain, comes from damaged nerve fibers that send faulty signals. Cleveland Clinic on neuropathic pain describes it as burning, stabbing or electric shock-like, with tingling and numbness. Tissue pain, called nociceptive pain, is the discomfort you feel when tissue is damaged, most often in muscles, joints and bones. WebMD on nociceptive pain describes it as dull, achy, sharp, throbbing or cramping.

Cleveland Clinic says to contact a provider for numbness, tingling, muscle weakness, uncontrolled twitching, or frequently dropping held objects. Keep a simple log of which words describe your pain, when it starts, and what changes it. Bring that log to your clinician. For nerve-type pain that starts in the spine, see pinched nerve symptoms and questions.

TENS and vagus stimulation are different things

TENS sends a low-voltage current through pads on the skin. The NHS guide to TENS says it is thought to work by encouraging the body to release endorphins, and that “TENS does not work for everyone.” Cleveland Clinic’s TENS overview lists fibromyalgia among the conditions where TENS is used.

The Cochrane review of TENS for fibromyalgia looked at 8 studies with 315 adults. Its authors rated the quality of evidence as “very low” and wrote there was “insufficient high-quality evidence to support or refute the use of TENS for fibromyalgia.” That review covers TENS, so its results do not transfer to vagus stimulation.

Does posture or text neck change the vagus nerve?

A 2025 cross-sectional study of 84 young adults in Cureus, the text neck and autonomic function study, found that a more forward head posture went with higher sympathetic activity and lower parasympathetic activity, measured through heart rate variability. The authors describe this as an association with forward head posture, measured through heart rate variability.

A 2025 Frontiers in Neurology paper by Hauser and colleagues proposes that forward-head phone use may affect the vagus nerve. It is based on a retrospective chart review of 234 patients, and the authors say symptom resolution with better vagus nerve measurements “will prove this hypothesis.” The authors also promote the neck treatments they propose, as described in the Hauser cervicovagopathy paper.

Where the devices reach the vagus nerve

The vagus nerve is one of the longest nerves in the body, according to Northwell’s vagus nerve stimulation overview. The Hasan Kalyoncu registry description says non-invasive transcutaneous devices reach it either through the auricular route at the ear or at the carotid. Hauser and colleagues describe the two vagus nerves as lying in the carotid sheath just in front of the cervical vertebrae.

Common mix-ups

• TENS is not vagus stimulation. Its trials and FDA class do not transfer.
• Headache devices are not fibromyalgia devices. The gammaCore indications cover headache only.
• “FDA approved,” “FDA cleared” and “wellness” are different. The terms table above shows the difference.
• Posture research is about association. It does not show that a posture change alters vagal function.

Who to ask before you try one

Start with your primary care clinician, who knows your full history and can look at any device you are considering. A neurologist can assess nerve-type symptoms, and a physical therapist can help plan movement and pain management. For back pain at work, see our living and working with back pain guide.

Questions that settle your next step

• Which FDA record covers the exact use the seller advertises? Ask for the number and check the FDA device approvals and clearances page.
• Is the device FDA approved, FDA cleared, or sold as a general wellness product? The maker’s own wording answers this.
• Do any of the cautions in the side effects table apply to you, such as an implanted device or a pacemaker?
• Has the sham-controlled trial, ClinicalTrials.gov record NCT07894588, posted results? Check the record for updates.
• What is the refund window, and what does the return cover? Check the seller’s order page before you buy.
• Bring a two-week log of your pain score, sleep and the time of day to your clinician.

By BackToHealthTroy.com Editorial Team

This article is for general information purposes only and does not constitute medical advice. Consult your doctor or qualified healthcare provider before making changes to your health routine.

If your pain feels burning, shooting or electric, or comes with tingling or numbness, a nerve is more likely involved. If it feels dull, achy or sore, stays in one spot and eases with rest, a muscle strain is more likely. Many back, neck and leg pains show a mix of signals, so the pattern matters more than any single word. Write down where the pain is, where it travels and what makes it worse. Those notes help you spot the warning signs that need fast care, and they are what a clinician will ask about first.

Nerve pain vs muscle pain at a glance (as of 2026-11-11)

The table below gathers what each named source says. Each row cites its source in the cell.

How does nerve pain differ from other pain?

The Cleveland Clinic neuropathic pain page says nerve pain arises when the nervous system malfunctions or is damaged, so damaged nerve fibers send incorrect signals to pain centers. Nerve pain can also show up as allodynia, which is pain from normally painless touch, and dysesthesia, which is an unpleasant or strange sensation.

Other pain works differently. WebMD’s nociceptive pain article defines it as “the discomfort you feel in response to damage to your tissues.” That kind most often comes from injury and commonly affects muscles, joints and bones.

How do I know if side pain is muscular?

Pain Management Specialists, a pain practice in Rockville and Frederick, Maryland, describes a strained muscle as an injury to the muscle fibers. The pain usually feels like soreness or a dull ache, with stiffness or tenderness in the area. Use these questions to check your side pain:

• Is it tender in one spot and stiff when you move?
• Does it stay in the muscle rather than travel?
• Does it ease with rest?
• Is there tingling, numbness or weakness? If so, a nerve may be involved, according to the same clinic.

Pinched nerve or pulled muscle: where you feel it

A pinched nerve happens when surrounding tissues put pressure on or irritate a nerve. A bulging spinal disc, called a herniated disc, is one example, according to Pain Management Specialists’ strained muscle guide. The location changes the pattern.

Neck and shoulder

A pinched nerve in the neck may radiate pain to the shoulders or arms. A muscle strain stays local. Muscle strains are most common in the lower back, neck, shoulders and legs. Cleveland Clinic lists frequently dropping held objects among the reasons to call a provider.

Mid back and shoulder blade

The NHS back pain page lists pain between the shoulders rather than the lower back as a reason to see a GP. A common cause of back pain is a strain, which is a pulled muscle.

Lower back

A strain is a common cause of back pain. A pinched nerve in the lower back may cause shooting pain down the leg, which is sciatica, and may weaken leg muscles (Pain Management Specialists). The NHS says back pain may occur with sciatica but is usually less severe than the leg pain. It also says you probably do not have sciatica if you only have back pain.

Leg

The NHS sciatica page says sciatica usually affects the bottom and back of one leg, often the foot and toes. It describes “a sharp, burning pain down the back of the leg,” plus tingling like pins and needles, numbness or weakness. Pain may get worse with movement, sneezing or coughing.

Can nerve pain feel like muscle pain?

It can be hard to tell from words alone. WebMD says nerve pain is more often described as burning, shooting, numbness, tingling or electric shock. Muscle and tissue pain is more often dull, achy or cramping. Sharp appears on the muscle list too, so pair it with where the pain goes and whether numbness comes with it.

Can a muscle strain cause nerve pain?

Pain Management Specialists says a strained muscle generally won’t cause tingling or numbness. Cleveland Clinic’s causes of nerve pain include nerve damage from trauma or surgery and spinal nerve compression or inflammation. A muscle strain is not on that list. The NHS back pain page does list a strain, a slipped disc and sciatica as separate causes of back pain.

What causes nerve tension in the neck?

The usual explanation is pressure. Pain Management Specialists says a pinched nerve happens when surrounding tissues press on or irritate nerves, and a bulging disc is one example. Cleveland Clinic lists spinal nerve compression or inflammation among the causes of nerve pain.

What does neuropathy feel like, and can it cause muscle pain?

The NHS peripheral neuropathy symptoms page groups the symptoms into three types. Muscle cramps and weakness appear in the motor type, so yes, muscle-like symptoms can be part of neuropathy.

Can nerve and muscle pain happen together?

Yes, and sciatica is the common example. Back pain may come with sciatica, but the leg pain is usually the stronger signal, according to the NHS. The NHS back pain page also lists many possible causes of back pain, and a strain is one of them. Cramps and weakness can appear alongside nerve symptoms, as the neuropathy table above shows.

Common mix-ups

• Sharp is on the muscle list too. WebMD includes sharp in its description of muscle and tissue pain.
• Coughing and sneezing show up on both lists. Muscle pain can worsen with coughing or laughing (WebMD), and sciatica can worsen with sneezing or coughing (NHS).
• Back pain alone points away from sciatica. The NHS says you probably do not have sciatica if you only have back pain.
• Numbness in the feet is on the neuropathy list. The NHS lists numbness, pins and needles and burning in the feet among neuropathy symptoms, so a pinched nerve is not the only possibility.

Warning signs that need prompt care

Go to A&E or call 999 now

The NHS sciatica page lists these. Do not drive yourself.

• Sciatica on both sides
• Severe weakness or numbness in both legs, or getting worse
• Numbness around or under the genitals or around the anus
• Difficulty starting to pee, being unable to pee, or losing bladder control
• Not noticing when you need to poo, or losing bowel control

The NHS back pain page adds chest pain, pain after a serious accident, and changes in genital sensation or sexual function. Cleveland Clinic lists severe pain, numbness or weakness that is “quickly getting worse,” a fast or irregular heartbeat, trouble urinating, and dizziness or fainting.

See a GP

• Pain that has not improved after a few weeks of home treatment, is getting worse, or stops you doing normal activities (NHS sciatica page)
• No improvement after a few weeks, stopping daily activities, unexplained weight loss, a lump, swelling or change in the shape of your back, no improvement with rest or worse at night, pain that is worse with sneezing or coughing, or pain between the shoulders rather than the lower back (NHS back pain page)

The NHS back pain page says to contact a GP or 111 urgently if you feel hot, cold, shivery or unwell, or have sudden severe or rapidly worsening pain.

Call a provider

Cleveland Clinic says to call a provider for numbness, tingling, muscle weakness, uncontrolled twitching, or frequently dropping held objects. For more on timing, see when to see a doctor for back pain.

Who examines nerve pain and muscle pain?

Start with a GP or primary care clinician. They examine the symptoms you describe and decide whether a nerve needs checking. If nerve symptoms persist, a neurologist is the specialist who examines them. A physical therapist works on movement and muscle problems. The NHS sciatica page says to see a GP if pain does not improve after a few weeks of home treatment.

To confirm whether a nerve is involved, a clinician examines the symptoms and reviews your history. Bring your notes to that visit.

How is TENS different from vagus stimulation?

The NHS TENS page describes a small portable machine that sends a weak electrical current through sticky pads on the skin for temporary pain relief. It says “TENS does not work for everyone.” Cleveland Clinic’s TENS page says “TENS therapy works well for a lot of people,” and that it “tends to work better for some than others.” The U.S. rule for TENS for pain relief identifies it as Class II, a device “used to apply an electrical current to electrodes on a patient’s skin to treat pain.”

A 2018 Cochrane TENS fibromyalgia review by Johnson and colleagues concluded there “was insufficient high-quality evidence to support or refute the use of TENS for fibromyalgia.”

Where does the vagus nerve fit into nerve and muscle pain?

The vagus nerve runs through the neck, and Cleveland Clinic’s vagus nerve stimulation page describes it that way. Researchers link it to the autonomic nervous system and often measure it indirectly through heart rate variability. Researchers have tested vagus stimulation for several pain conditions. Here is what each study reports, with its people, comparison and length.

What the pain studies report

Most of these studies are small, and their authors ask for larger, longer trials. Each result belongs only to the device and people in its row.

FDA status of vagus devices

FDA decisions cover specific devices for specific uses. The table lists what each record covers.

Cleveland Clinic’s VNS page says external devices exist, and that “The long-term side effects of commercial VNS devices are yet to be fully known.” The implanted Vivistim and VNS Therapy systems are surgical devices, not the consumer neck or ear wearables.

What the words on vagus devices mean

Neck posture and the vagus nerve

A 2025 cross-sectional study in Cureus, the Sureshbabu et al., 2025 text neck study, included 84 people aged 19 to 45. Forward head posture went with more sympathetic activity and less parasympathetic activity, measured through heart rate variability. The authors describe forward head posture as “associated with increased sympathetic and decreased parasympathetic modulation.” Heart rate variability is an indirect measure.

A 2025 paper in Frontiers in Neurology, Hauser et al., 2025 cervicovagopathy paper, proposes that forward-head phone use slowly stretches neck ligaments and affects the vagus nerve. The authors call this a hypothesis, drawn from a retrospective chart review of 234 patients, and say that resolving symptoms alongside improved vagus nerve measurements “will prove this hypothesis.” The authors also promote the cervical treatments they propose.

Our guide on whether neck tension or posture can affect the vagus nerve looks at what these early studies do and do not show.

The best evidence for auricular stimulation, according to Likar et al., 2023, is for chronic low back pain, chronic cervical syndrome, chronic abdominal pain and chronic migraine, plus some postoperative pain settings. Most studies in that review showed reduced analgesic or opioid intake.

For a closer look at one of those uses, read what studies show on vagus nerve stimulation for chronic back pain, including where the evidence is still limited.

For a closer look at one of those uses, read what studies show on vagus nerve stimulation for chronic back pain, including where the evidence is still limited.

Questions that settle your next step

1. Is there numbness, tingling, weakness, or dropping held objects? If so, Cleveland Clinic says to call a provider.
2. Does the pain travel down an arm or leg, or does it stay in the muscle? Travel points toward a nerve, according to Pain Management Specialists.
3. Has the pain stopped you doing normal activities, or has it not improved after a few weeks? The NHS says to see a GP.
4. Is any warning sign from the list above present? If so, follow the NHS advice to go to A&E or call 999.

What to write down before your appointment

Note where the pain is, the words you would use for it, what makes it worse, and whether it spreads or comes with numbness or weakness. Add the date it started. Bring the list to your visit. Our guide to low back pain red flags explains what to record.

By BackToHealthTroy.com Editorial Team

This article is for general information purposes only and does not constitute medical advice. Consult your doctor or qualified healthcare provider before making changes to your health routine.

If you own a TENS unit and wonder whether it does what a vagus nerve stimulator does, the makers of dedicated vagus devices say it does not, while researchers at the Feinstein Institutes are still studying TENS-style units for vagus stimulation. A TENS unit sends a low-voltage current through pads on the skin, aimed at nerves near the area that hurts, for temporary pain relief. A vagus nerve stimulator sends mild electrical pulses to the vagus nerve, one of 12 pairs of cranial nerves. Some vagus devices are cleared or approved for specific medical uses, and consumer models are sold as general wellness products. Truvaga and gammaCore both say a TENS unit is not the best option for vagus nerve stimulation.

To see how nerve pain differs from muscle pain, and where vagus nerve research fits, read our guide to the vagus nerve and pain.

TENS unit vs vagus nerve stimulator at a glance

Facts as of 2026-11-11.

Can a TENS unit work as a vagus nerve stimulator?

The makers of dedicated vagus devices say no. Truvaga’s blog says TENS units “are not designed or recommended for vagus nerve stimulation.” gammaCore says a TENS unit may give minor stimulation of the vagus nerve when applied to certain areas of the body, but it is not designed for use around the neck and head.

The Feinstein Institutes vagus nerve page at Northwell describes TENS pads placed in specific body areas as one approach that can reach different areas of the vagus nerve. The same page says researchers there have launched initial studies of small wearable TENS units for that purpose.

The NHS TENS page and the Cleveland Clinic TENS guide both say TENS should not be used on the neck.

What a TENS unit is for

The NHS describes TENS as a small portable machine that sends a weak electrical current to nerves through sticky pads on the skin, for temporary pain relief. Listed uses include period pain, labour pain, sports injury pain, and pain from conditions such as arthritis or endometriosis. The NHS says it is “thought to work by encouraging your body to release natural painkillers called endorphins,” and also by blocking pain signals reaching the brain.

Cleveland Clinic says the pads go along nerve pathways near the painful area. The federal TENS device rule defines the device as “a device used to apply an electrical current to electrodes on a patient’s skin to treat pain.” It is classified as Class II.

What the research says about TENS for pain

Cleveland Clinic says “TENS therapy works well for a lot of people,” but also that it “tends to work better for some than others,” that there is not enough research to explain exactly why, and that some studies suggest a placebo works just as well.

The Cochrane review on TENS for fibromyalgia (Johnson et al., 2018, searches to 18 January 2017) included 8 studies: 7 randomized controlled trials and 1 quasi-randomized trial. They covered 315 adults, 299 of them women, aged 18 to 75. Two studies, with 82 participants, compared TENS with placebo TENS.

In one pilot crossover study of 43 people, pain on movement fell 11.1 mm on a 100-mm scale with TENS and 2.3 mm with placebo TENS, after one 30-minute treatment. The review reports no significant difference for pain at rest. No serious adverse events were reported, and 3 participants had minor discomfort in total.

The review’s authors rated the quality of the evidence “very low” and wrote that there was “insufficient high-quality evidence to support or refute the use of TENS for fibromyalgia.”

What a vagus nerve stimulator is

The vagus nerve is the longest cranial nerve. It runs from the brainstem through the neck to the chest and abdomen, and it is part of a circuit linking the neck, heart, lungs and abdomen to the brain, according to the Cleveland Clinic vagus nerve guide. Devices fall into four groups:

• Implanted VNS: a device placed through surgery. Cleveland Clinic says it is approved to treat difficult-to-control epilepsy, depression, and as a rehab aid for stroke.
• Neck-side non-invasive devices: gammaCore is a hand-held device applied at the neck. Its maker says it sends “a mild electrical stimulation to the vagus nerve through the skin.”
• Ear-based non-invasive devices: Feinstein describes a stimulation device attached to different parts of the ear.
• Consumer wellness devices: neck-worn, ear-worn or vibration wearables. Their makers describe them as general wellness products.

Are vagus nerve stimulators FDA approved?

These words mean different things, and the difference matters when you compare devices. The FDA device approvals and clearances page sets out the routes.

• Approved: the FDA calls premarket approval (PMA) “the most stringent type of device marketing application.” The implanted Vivistim system has PMA record P210007.
• Cleared: a 510(k) is a premarket submission “to demonstrate that the device to be marketed is as safe and effective, that is, substantially equivalent” to a device already legally marketed. gammaCore is cleared, not approved, for its listed uses.
• General wellness: the label consumer makers use. Truvaga says its devices “are considered a wellness product and are not covered by health insurance.” Apollo Neuro says its wearable “does not require FDA approval for sale.”
• CE and FCC: Nurosym says it is “a certified device (CE) in Europe.” Pulsetto says its FCC certification “means that Pulsetto is approved for well-being use.” The FCC equipment authorization page covers radio frequency devices that “have the potential to cause interference to radio services.”

Is gammaCore’s FDA clearance for pain?

The FDA’s Indications for Use for gammaCore Sapphire (FDA gammaCore Sapphire clearance, decided in 2021) say the device “is intended to provide non-invasive vagus nerve stimulation (nVNS) on the side of the neck.” Its listed uses are preventive and acute treatment of migraine headache, cluster headache, hemicrania continua and paroxysmal hemicrania, in the age groups the form names. None of these is back pain, neck pain, fibromyalgia or general pain. The clearance belongs to gammaCore alone. electroCore says gammaCore is available by prescription only.

Do any vagus nerve stimulators actually work?

Each study below concerns one device type, so read it for that device only.

For implanted systems, the FDA record for Vivistim says the system “is intended to be used to stimulate the vagus nerve during rehabilitation therapy in order to reduce upper extremity motor deficits and improve motor function in chronic ischemic stroke patients with moderate to severe arm impairment.” Vivistim is an implanted system paired with rehabilitation therapy, not a consumer device.

Cleveland Clinic says that approval was based on a 108-patient study. There were 53 people in the study group and 55 in a control group. All of them were asked to complete 300 to 400 physical therapy exercises for 90 minutes a day, three times a week, for six weeks. The study group received VNS throughout those sessions. Their average limb mobility score rose 5 points, against 2.4 points in the control group. At 90 days, about 47% of the study group had a 6-point or more improvement, compared with 24% of the control group.

For headache and pain, the Pellow 2025 review of nVNS, published in the Scandinavian Journal of Pain, looked at randomized trials from 2010 to 2023. It compared non-invasive vagus nerve stimulation (nVNS) with heart rate variability biofeedback. From 1,474 records, 10 articles were included, covering 813 people: 763 on nVNS and 50 on biofeedback. Of the nine nVNS studies, six were on headache or migraine (603 people), two on fibromyalgia symptoms (138 people), and one on chronic low back pain (22 people). Across the nVNS studies, 6 reported significant results for pain intensity, 3 for episode frequency and 3 for medication use. For chronic pain conditions, the authors concluded that the literature is insufficient: “insufficient literature exists to support either approach,” meaning nVNS or heart rate variability biofeedback. The moderate-to-high quality rating applies to headache frequency and tolerability, not to chronic pain.

Consumer makers describe wellness goals. Truvaga says its device is intended to “support a balanced nervous system.” Apollo Neuro says its wearable “is intended to help manage stress, challenging life transitions, and to promote a healthy lifestyle.” Pulsetto says it is “considered a general wellness device” that “doesn’t claim to diagnose, treat, cure, or prevent any medical condition.”

What are the downsides of vagus nerve stimulation?

For implanted VNS, Feinstein says implantation takes about one to two hours, and patients can usually go home in one to two days. Cleveland Clinic says that for all FDA-approved uses, it may take one year or longer to know if or how well VNS is working for you. It lists these reasons to call your healthcare provider right away: signs of infection at the incision; a constantly hoarse voice; stimulation that becomes painful, causes choking, breathing or swallowing problems, or changes your heart rate; and increased drowsiness.

For non-invasive consumer devices, Truvaga says that in clinical studies “less than 5% of participants” had mild effects such as site discomfort or redness, muscle twitching, localized face, head or neck pain (including toothache), mild headache or mild dizziness.

What are the downsides of using a TENS unit?

Cleveland Clinic lists adhesive allergy, prickling or tingling, and rare electrode burns as side effects. The NHS TENS page lists these cautions:

• Epilepsy, or a pacemaker
• Pregnancy, unless a doctor or midwife says so
• Irritated, broken, infected or numb skin
• The neck, mouth or eyes
• The chest and back at the same time, during sleep, in the bath or shower, or while driving

Cleveland Clinic also lists heart disease, cancer, deep vein thrombosis and bleeding disorders among conditions to avoid TENS with.

Where should a TENS unit never go?

Per the NHS and Cleveland Clinic, keep TENS off these areas:

• The neck, including the front or side of the neck
• The head, eyes, mouth and genitals
• Infected, damaged, irritated, broken or numb skin, and recently radiated areas

For placement questions, ask a physical therapist or your primary care clinician.

Why a TENS unit is not a vagus nerve stimulator

• Target. TENS is built for pain near the painful area. Truvaga’s blog says TENS devices are “built for pain relief in muscles and peripheral nerves, not for stimulating the vagus nerve in the neck.”
• Waveform. Truvaga and gammaCore both describe TENS as square-wave. gammaCore says its device uses a sine wave, and Truvaga says its devices use smooth sine waves rather than the block waves of a TENS unit.
• Purpose. The NHS describes TENS for temporary pain relief. The vagus devices above are cleared for specific headache uses, approved for implanted uses, or sold as general wellness products.

Consumer vagus devices at a glance

Each maker describes its own product in these words.

Who each maker says should skip the device:

• Truvaga: anyone with an active implantable medical device, such as a pacemaker, hearing aid implant or any implanted electronic device.
• Pulsetto: the list includes heart conditions, a history of seizures or fainting, neck surgery, implants or metal in or near the neck, pregnancy, cancer treatment, and broken or irritated skin on the neck. It says the product is for adults 18 and over.
• Nuropod: people with a permanent implanted metallic or electronic device, or jewelry close to the ear tragus; pregnant women; children; and people who have had surgery to cut the vagus nerve. Its contraindication list also includes severe coronary disease or a heart attack within 5 years, unless a health professional advises otherwise.

Common mix-ups to avoid

• Pain device vs vagus device. A TENS unit and a VNS device both use electrical stimulation, but they target different nerves and serve different purposes.
• Electrical current vs vibration. Apollo Neuro describes sending vibration patterns through its wearable. Its help articles describe vibration rather than electrical current.
• Where the device sits. Nuropod is an ear device, Pulsetto is a neckband, and gammaCore is applied at the neck. Each device’s clearance or claim applies only to that device.
• Clearance vs wellness vs CE vs FCC. Each term is a different regulatory status. Read the exact wording on the product’s own page.

Questions that settle your next step

• If the pain is nerve-type (burning, shooting, numbness or tingling), the Cleveland Clinic neuropathic pain page lists numbness, tingling, muscle weakness, uncontrolled twitching and frequently dropping held objects as reasons to call a provider.
• If pain is not improving, the NHS sciatica page says to see a GP when pain has not improved after a few weeks of home treatment, is getting worse, or stops you doing normal activities.
• Emergency signs. The NHS sciatica page says to go to A&E or call 999 for sciatica on both sides, severe or worsening weakness or numbness in both legs, numbness around the genitals or anus, or bladder or bowel changes. Do not drive yourself.
• Back pain red flags. See when to see a doctor for back pain, and the NHS back pain guide.
• Mood as the goal. Cleveland Clinic says VNS for depression is usually not recommended until medications, in combination with psychotherapy, have first been tried. A psychiatrist or psychologist can talk you through that.
• Wider back and neck options. See back and neck pain relief for more context.

Before you choose a device

• Check the wording on the maker’s page: cleared, approved, general wellness, CE and FCC each mean something different.
• Read the device’s own warnings and its list of who should not use it.
• Check today’s price directly with the company. Prices and bundles change.
• If you have an implanted device, a pacemaker or a seizure history, ask your clinician before using any device that sends current to the body. Ask them how often and how long to use one, too.

By BackToHealthTroy.com Editorial Team

This article is for general information purposes only and does not constitute medical advice. Consult your doctor or qualified healthcare provider before making changes to your health routine.

If you are searching for the best supplement for osteoporosis, the short answer is this: as of November 2026, the JAMA review recommends antiresorptive medicines for people at high fracture risk and recommends calcium and vitamin D intake alongside; ask your clinician how they fit together. Calcium and vitamin D are the supplements that major bone-health organisations name, and the International Osteoporosis Foundation recommends them alongside osteoporosis treatment. This page lays out each option side by side so you can decide what fits your situation.

What is osteoporosis, and why does it change your choices?

As of November 2026, the NIAMS osteoporosis overview describes osteoporosis as a bone disease in which bone mineral density and bone mass decrease, which can raise the risk of fractures. NIAMS calls it a “silent” disease because most people have no symptoms until a bone breaks. Fractures happen most often in the hip, the spine and the wrist.

Calcium and vitamin D: the two nutrients to know

The NIAMS page says a nutritious diet rich in calcium and vitamin D helps maintain good bone health. The Office on Women’s Health osteoporosis page explains that calcium and vitamin D work together to build and maintain strong bones. As of November 2026, the IOF notes that sunlight supplies most of the vitamin D your body makes, but sunlight is not always reliable because season, latitude, sunscreen and skin pigmentation all change how much the skin produces.

What are the best foods for bone health?

Start with food. The Office on Women’s Health says it is best to get calcium from food, and that supplements are an option when food falls short. Foods rich in calcium include dairy, leafy greens and fortified products. Foods with vitamin D include oily fish, eggs and fortified milk. Our best foods for osteoporosis guide turns these into meal ideas.

Are calcium supplements safe?

Calcium supplements are sold at grocery and drug stores. The Office on Women’s Health advises talking with your doctor or nurse before you take one, so you can choose the right kind and amount for you. If you take other medicines, ask your pharmacist whether calcium could interact with them.

Is high-dose vitamin D for osteoporosis a good idea?

The IOF says combined calcium and vitamin D supplements are recommended for people with osteoporosis, to make sure they get enough of both and to get the most from osteoporosis treatment. It also recommends that adults aged 60 and older take a vitamin D supplement to support bone health and help reduce falls. For a high-dose plan, ask a clinician first; the evidence here does not set a high-dose recommendation. For the two forms you will see on labels, read our Vitamin D3 vs D2 for bone health (our research library) guide.

Which calcium is best absorbed?

Absorption depends on vitamin D as well as the calcium itself, since the Office on Women’s Health says vitamin D helps your body absorb calcium. Our guide to how to read a supplement facts panel shows where the calcium amount and the form are printed, so you can compare labels. Ask a pharmacist or clinician which form fits your routine.

What vitamins help build strong bones in children?

Childhood is when bone is built. The Office on Women’s Health says building strong bones in childhood and the teen years helps prevent osteoporosis later, and that girls develop about 90% of their bone mass by age 18. The IOF notes that severe vitamin D deficiency in children can cause bone deformities called rickets. Food and sunlight come first, and a children’s supplement is a question for your child’s doctor.

Is there one best vitamin for bone density?

No single vitamin is the answer. Calcium and vitamin D are paired because they work together. A multivitamin may contain some of these nutrients, so check its label for calcium and vitamin D amounts rather than trusting the word “bone” on the front.

What are the prescription options, and what do the studies show?

There is no single miracle drug. As of November 2026, the 2025 JAMA review on osteoporosis recommends antiresorptive medicines, bisphosphonates or denosumab if bisphosphonates are contraindicated, for people at high fracture risk. That includes people with a T score of -2.5 or lower, a past spine or hip fracture, or a 10-year absolute fracture risk of 20% or more. Anabolic medicines are considered for very high-risk people, followed by an antiresorptive.

In that review, for antiresorptive agents (bisphosphonates or, if contraindicated, denosumab) in high-risk patients, the abstract reports a risk difference of -52 per 1,000 person-years for vertebral fractures (95% CI -95 to -18) and -6 per 1,000 person-years for hip fractures (95% CI -11 to -1). A person-year is one person followed for one year. These figures are for medicines, not supplements, and they are not a promise for any one person.

The 2019 Lancet review on osteoporosis says that for people at high fracture risk, the benefit-risk profile is likely favourable for up to 10 years of bisphosphonates or denosumab. It also says high-risk people often do not receive adequate treatment. The JAMA review reports that fracture liaison services, programmes that manage patients after a fracture, raised medicine start and adherence to 38%, compared with 17% for patients who did not receive them. For a side-by-side guide to medicine options, costs and side effects, see Osteoporosis treatment 2026: options, costs, side effects.

Are there newer treatments or a breakthrough?

The JAMA review says anabolic medicines can be considered for very high-risk people, followed by an antiresorptive. Neither review names a newest breakthrough, and the Lancet review dates from 2019, so ask your clinician which options are current for you. Read the current prescribing information for any medicine you are considering, and ask how it fits your fracture risk.

What do Japanese people do for osteoporosis?

This page covers the approaches recommended by NIAMS, the Office on Women’s Health, the IOF and the two reviews above. Practice differs by country. For the Japanese approach, ask a clinician familiar with Japanese care or look up the current guidance from the Japanese osteoporosis society.

What if I am being treated for cancer?

NIAMS says some cancer medications may increase the risk of osteoporosis, including hormone-based treatments for breast and prostate cancer. Ask the team treating your cancer before you add calcium or vitamin D, and ask whether they recommend bone checks during treatment.

What else helps, besides supplements?

NIAMS lists steps that help prevent osteoporosis and fractures:

• Stay physically active, with weight-bearing exercise such as walking.
• Drink alcohol in moderation. The Office on Women’s Health says one drink a day at most for women.
• Do not smoke, or quit if you do.
• Take prescribed medicines as your clinician directs.
• Eat a nutritious diet rich in calcium and vitamin D.

The JAMA review also recommends resistance exercise, such as squats and push-ups, and balance exercise, such as heel raises and standing on one foot.

How do I know if I need a bone-density test?

The Office on Women’s Health says a doctor may suggest a bone density test if you are 65 or older, or younger with risk factors. The usual test is a DXA scan, a low-radiation x-ray of your bones. The same page says screening is covered by most insurance plans, including Medicare Part B. Check with your insurer about what your own plan covers.

Before you choose: a checklist

• Ask your doctor whether a bone-density test makes sense for you, and what your fracture risk is.
• Ask whether calcium and vitamin D supplements fit your diet, and how much you need in total.
• If you take other medicines, ask your pharmacist about possible interactions.
• Read the label for calcium and vitamin D amounts, and check the form.
• Look for third-party testing. Our third-party tested bone supplements (our research library) guide explains what that testing covers.
• Prices vary by brand and store and change over time, so check the current price and the seller’s return terms before you order.

Take this list to your next appointment. It turns the question from “which product” into “what does my fracture risk call for,” and that is the conversation that gets you the right answer.

By BackToHealthTroy.com Editorial Team