CompletedNot ApplicableInterventional

Can blocking the nerve to the back muscle predict the outcome of stimulating back muscles in managing pain due to muscle dysfunction?

Chronic lower back pain affects many people and can be difficult to treat. One common cause is weakness in the deep muscles that keep the spine stable. The ReActiv8 device is a small implant that sends gentle electrical pulses to these muscles, helping them strengthen and reduce pain over time. However, it helps some people more than others. This study in Leeds aims to find out if temporary nerve-blocking injections can predict who will benefit most from the implant. Participants receive two test injections to temporarily numb the nerves to the back muscles, followed by the fitting of the ReActiv8 device. Researchers will track pain relief and daily activity over 12 months. Taking part helps doctors understand how to choose the right patients for this therapy in the future, potentially sparing people from treatments that might not work for them.

At a glance

Status

Completed

Phase

Not Applicable

Sponsor

Leeds Teaching Hospitals NHS Trust

Enrolment target

Start

01 Feb 2022

Estimated completion

31 Dec 2024

Chronic low back pain

What is this study about?

Many people live with ongoing lower back pain that does not improve with standard physiotherapy or medicines. In many cases, this pain happens because the deep muscles supporting the spine—known as the multifidus muscles—have become weak or stopped working properly. When these muscles fail to support the back, daily movements can cause ongoing irritation and pain.

The ReActiv8 system is an implanted medical device designed to treat this specific issue. It sits under the skin and delivers mild electrical pulses to the nerves that control these deep back muscles. Over time, these pulses encourage the muscles to contract and rebuild their natural strength, helping to stabilise the spine and relieve discomfort.

While ReActiv8 has helped many people, it does not work equally well for everyone. In this study, doctors want to see if a simple, temporary nerve-numbing injection (called a medial branch block) can tell them in advance who will get the best results. If the injection successfully identifies who will improve, doctors will be able to recommend the device with much greater confidence.

By taking part, participants receive specialised assessment and care at Leeds Teaching Hospitals NHS Trust, while providing vital information that could shape how chronic back pain is treated across the NHS.

Key takeaways

Tests whether simple nerve injections can predict success with the ReActiv8 muscle stimulation implant.
Aimed at adults aged 18 to 75 with chronic lower back pain that has not improved with standard care.
Involves two diagnostic spinal injections, an implant procedure, and 12 months of follow-up check-ups.
Conducted at Leeds Teaching Hospitals NHS Trust in the UK.
Participation is completely voluntary and you can withdraw at any time.

Who may be eligible?

This study is open to adults aged between 18 and 75 who have had persistent lower back pain on most days for at least 12 weeks. To be considered, you should have already tried standard medical management (such as medication or physiotherapy) for at least three months without getting enough relief.

You will not be able to join if your leg pain is worse than your back pain, or if you have nerve issues such as numbness or weakness travelling below your knee. The trial also cannot accept people who have had previous lower back surgery, those who have been diagnosed with curvature of the spine (scoliosis), or people with a body mass index (BMI) greater than 35.

In addition, participants must not be taking very high daily doses of strong opioid painkillers, and must not have active depression or ongoing legal claims related to their back injury.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you between 18 and 75 years old?
Have you had lower back pain on most days for at least 12 weeks?
Have you tried treatments like physiotherapy or medicines for at least 3 months without enough relief?
Is your back pain worse than any pain you feel in your legs?
Are you free from previous lower back surgery and severe spine conditions like scoliosis?
Is your body mass index (BMI) 35 or lower?

Answer every question to see your result.

What does participation involve?

If you take part, your care will be based at Leeds Teaching Hospitals NHS Trust. You will first have two separate nerve-blocking injections in your back using local anaesthetic. These injections temporarily numb the small nerves going to your back muscles so doctors can measure how much your pain changes over the following six hours. You will then have a minor surgical procedure to fit the ReActiv8 device under your skin. Doctors will place you into one of three study groups depending on how your pain responded to the initial injections. After your device is switched on, you will attend follow-up hospital visits at 1, 3, 6, and 12 months. During these visits, the team will check your device, ask you to complete questionnaires about your pain and quality of life, and perform simple movement tests. Your total involvement in the study will last around a year after the device is fitted.

Potential risks and benefits

Taking part may help strengthen your back muscles, reduce your daily pain, and lower your need for painkillers, though these benefits cannot be guaranteed. You will also help doctors improve future care for people with chronic back pain. The main risks involve temporary soreness, bruising, or brief leg numbness following the spinal injections. As with any minor procedure, there is a very small risk of infection or nerve irritation. X-rays are used to guide the needles and implant, which involves a tiny amount of radiation; this carries an extremely small theoretical increase in lifetime cancer risk (raising it by about 0.02%). Taking part is entirely voluntary, and you are free to leave the study at any time without your regular NHS care being affected.

Locations (1)

Leeds General Infirmary
Approximate
Leeds, England

Common questions

What is the ReActiv8 device?

It is a small, battery-powered device implanted under the skin that sends mild electrical signals to deep back muscles to help them contract, strengthen, and support your spine.

Will having the injections hurt?

A local anaesthetic is used to numb your skin first. You may feel some pressure or brief stinging during the injection, and mild tenderness for a few days afterwards.

Will taking part cost me anything?

No, the study assessments, injections, and ReActiv8 implant are provided free of charge as part of the clinical trial.

What happens if the injections do not take away my pain?

That is still useful information for the study. Participants are placed into different groups based on how much relief they feel, even if the pain reduction is small.

Can I leave the study if I change my mind?

Yes, you can withdraw from the study at any point without giving a reason. Your usual medical care will continue as normal.

How to find out more

Emma Binns

emma.binns1@nhs.net +44 (0)113 3926234 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.