As a Physiotherapist specialising in spinal conditions, I’ve written previously about how not all Sciatica (nerve related leg pain) is the same, read more about it here. However, many clinicians will still routinely prescribe neural flossing, commonly known as sliders and tensioners to clients who have ‘sciatica’ or other nerve related limb pain (technically termed radicular pain). 

I even used to be one of those physios teaching my clients how to floss their nerves and coordinate head movements to bias one nerve over the other - I’ve been there!

Over time, I found that not all my clients were getting the results they’d hoped for, despite how it made ‘sense’ to keep the nerve mobile, and now, there’s a recent study by Sousa L et al (2022) that shows it doesn’t provide significant benefit to some people with radicular pain. 

So, do we completely throw out neural flossing? How do we know if it’ll help? 

WHAT IS NEURAL FLOSSING? 

To put it simply, neural flossing, sliders & tensioners, or neurodynamic mobilisations are prescribed exercises that aim to specifically target a nerve by placing joints and the spine in specific positions. 

Nerves are physical structures in our body that travel in a specific route, so if you know its path, you’d be able to come up with the specific joint positions you need to be in to stretch or relax the nerve. 

I like to describe these exercises as being something like ‘flossing your teeth, but for your nerves”. 

HOW DOES IT HELP? 

The theory is that the nerves, which are normally quite mobile structures, can become much more sensitive to stretch and compressive pressure. 

What causes the sensitivity to stretch and compression?

Chemical irritation.

What causes chemical irritation?

Inflammation. 

What has been proven to help mitigate and reduce inflammatory pain?

Graded exposure to movement!

Neural flossing has been shown to produce immediate, clinically relevant effects, (Nee et al 2012). 

This is where the physio world jumped on the neural flossing trend and started prescribing it to EVERYONE with sciatica, or nerve induced limb pain (arm or leg). 

But was that the right thing to do?

WHO CAN BENEFIT FROM NEURAL FLOSSING? 

In case you hadn’t read my previous blog about the different types of Sciatica that people can get, the main point there is that not all leg/nerve pain is the same. 

They have different mechanisms of how pain is experienced and so their management will differ too. To narrow down which category you fall into, reach out to us for a comprehensive assessment to get you on the right track to recovery.  

In my previous blog, I broke down the types of nerve induced leg/arm pain very simply into 

1: Spinal causes 

2: Somatic causes 

3: Other causes. 

For a more technical breakdown, here’s how I break it down in my head. 1-3 are further subgroups of Spinal Causes, and Somatic Causes are classed as musculoskeletal.

1: Neuropathic Pain (Hypersensitivity) 

2: Compression Neuropathy 

3: Peripheral nerve sensitisation 

4: Musculoskeletal (Somatic) 

The subgroup of clients that would most likely benefit from neural flossing belong to PERIPHERAL NERVE SENSITISATION (3). 

HOW DO YOU KNOW IF NEURAL FLOSSING IS RIGHT FOR YOU?

If you’re suffering from nerve related leg pain, or nerve pain in your upper limb, we would always recommend getting it assessed by a health professional experienced in diagnosing complex nerve pain. 

As a general guideline, here’s the main things I look for 

1. Mechanically driven symptoms (specific movements/postures aggravate pain). 

2. No neurological deficit (sensation and muscle function intact). 

3. Positive neural tissue sensitivity tests.

4. Symptoms that are relatively acute (<3-6 months history). 

This is by no means a full diagnostic criteria, and you should always get an experienced professional to perform a thorough testing procedure to pinpoint what’s going on. 

WHAT ABOUT THE CONFLICTING EVIDENCE ON NEURAL MOBILISATIONS?

Earlier studies by Nee et al 2012, Su Y et al 2016 and Basson et al 2017 have all shown improvements in pain and disability by using neural flossing and mobilisation techniques. 

However, a more recent study by Sousa et al 2022 showed no significant change. A deeper dive into this research was that it was testing whether the addition of neural flossing to McKenzie extension exercises would be significantly better than just McKenzie exercises alone. And it concluded that the addition did not bring about any significant improvement! 

(Bit of background, McKenzie extension exercises are a common prescription used to help people with discogenic low back and leg pain)

I wouldn’t read too much into the Sousa study because in my clinical practice, I’ve found that the prescription of McKenzie based exercises without neural flossing will ALREADY help reduce symptoms in the majority of discogenic clients. Which is essentially what the study proves.

BUT - in the clients that have persistent leg/arm pain, or need more neural mobility, I could always add in neural flossing later on with good effect.

Why not just add neural flossing at the start then?

In my opinion, flossing can be quite aggravating, especially in a client who has quite a high ‘SIN’ (Severity, Intensity, Nature). The last thing we want is someone who has high levels of pain, to be stretching their irritable nerve and giving them even more pain. I’d rather gradually introduce the flossing later on if required when they can be more tolerant to it. 

CONCLUSION

I believe that neural flossing can be the right tool for the right person, at the right time.

To find out if it’s for you, get it assessed to see if you fall into the ‘Peripheral Nerve Sensitisation’ category. If so - you would probably benefit from it. 

Otherwise, it could aggravate your symptoms! For example - I would very rarely prescribe neural flossing for someone who falls into the ‘Neuropathic Pain’ group, at least in the early stages. 

If you’re struggling with what you think is nerve related leg pain, get it assessed by a physiotherapist first to determine if neural flossing is appropriate for you! 

References: 

Basson A et al 2017. The Effectiveness of Neural Mobilization for Neuromusculoskeletal Conditions: A Systematic Review and Meta-analysis

Y su et al 2017.  Does Evidence Support the Use of Neural Tissue Management to Reduce Pain and Disability in Nerve-related Chronic Musculoskeletal Pain? A Systematic Review With Meta-Analysis

Sousa et al 2022. Neurodynamic exercises provide no additional benefit to extension-oriented exercises in people with chronic low back-related leg pain and a directional preference: A randomized clinical trial

ABOUT THE AUTHOR 

Ryan Tan is our Clinical Director and Physiotherapist here at Physiologic Hong Kong. He’s had over 10 years of experience as a sports and spinal Physiotherapist. He has acquired his Certificate of Spinal Manual Therapy (COSMT), which is an intensive course focussing purely on treating spinal conditions. He has extensive experience working in Complex Pain Clinics in London, treating complex spinal conditions that have been through Spinal Surgeries and procedures. Ryan now works closely with Orthopaedic Spinal Specialists to provide collaborative care and expert Physiotherapy treatment to those suffering from back pain. If you have a complex Spinal injury that hasn’t been able to be resolved, contact us for a no obligation assessment!