Research Review: Neural Mobilization

Carpal Tunnel Syndrome and Massage

Peripheral Nerve Entrapment: Pathophysiology

Non-pharmacological therapeutic interventions are being embraced by the medical community because they are simple to carry out, economical, and have relatively minor side effects. One treatment approach that can be used as part of an individualized multi-modal program to manage persistent pain is neural mobilizations. 

In the book Clinical Neurodynamics, physiotherapist Michael Shacklock provides some insight into how mechanical irritation may lead to localized nerve inflammation.

As peripheral nerves pass through the body they may be exposed to mechanical or chemical irritation at different anatomical points. Prolonged compression or fixation of a nerve may result in a reduction of intraneural blood flow. This then triggers the release of pro-inflammatory substances (calcitonin gene-related peptide and substance P) from the nerve. This is referred to as neurogenic inflammation and it can disrupt the normal function of nerves even without overt nerve damage, it can also contribute to the initiation and propagation of chronic pain.

In these cases five minutes of passive mobilization may help to diminish intraneural edema and/or pressure (Boudier-Revéret et al. 2017). This will have a modulatory affect on peripheral and central processes.

In longer standing cases the development of fibrosis, may contribute to peripheral nerve dysfunction. Geoffrey Bove has investigated how trauma and ongoing inflammation can be a contributing factor to connective tissue changes (increased collagen and TGF-β1 deposition). This process has been described as a progression from densification (alterations of loose connective tissue) to fibrosis (alterations of collagen fibrous bundles).

Functionally, these changes may influence biomechanical properties secondary to tissue adherence or tethering structures to each other. It may also induce chronic compression of peripheral nerves (ie. carpal tunnel syndrome, hamstring syndrome, meralgia paresthetica, infrapatellar syndrome etc...). If implemented early the application manual therapy that may attenuate tissue fibrosis and restore motility of peripheral nerves (Bove et al. 2016 & Bove et al. 2019).

Does Neural Mobilization Work?

There is a fair bit of research to support the use of nerve mobilizations for musculoskeletal pain. The most recent meta-analysis on the topic was published in The Journal of Orthopaedic & Sports Physical Therapy. This study suggests that nerve mobilizations are useful for patients with back, neck and foot pain (Basson et al. 2017).  

In terms of mechanism of action, the underlying effects of neural mobilization are complex and multifactorial. In addition to endogenous pain modulation, soft tissue mobilization may help diminish intraneural edema and expedite clearance of pro-inflammatory cytokines. Additionally, an interesting area of research is to what degree can soft tissue mobilization mitigate the development of post-inflammatory connective tissue fibrosis, and how does this effect epineurial and perineurial structures.

Then if massage therapy is applied with an optimized dosage, what are the implications for patients with repetitive strain disorders or peripheral neuropathy.

Demonstrating sliders and tensioners for the upper extremity.

Demonstrating sliders and tensioners for the lower extremity.

More to Explore

Andrade et al. (2018). The potential role of sciatic nerve stiffness in the limitation of maximal ankle range of motion. Sci Rep.

Basson et al. (2017). The Effectiveness of Neural Mobilization for Neuro-Musculoskeletal Conditions: A Systematic Review and Meta-Analysis. J Orthop Sports Phys Ther.

Boudier-Revéret et al. (2017). Effect of neurodynamic mobilization on fluid dispersion in median nerve at the level of the carpal tunnel: A cadaveric study. Musculoskelet Sci Pract.

Bove, G.M. (2008). Epi-perineurial anatomy, innervation, and axonal nociceptive mechanisms. J Bodyw Mov Ther.

Bove et al. (2016). Manual therapy as an effective treatment for fibrosis in a rat model of upper extremity overuse injury. J Neurol Sci.

Bove et al. (2019). Manual therapy prevents onset of nociceptor activity, sensorimotor dysfunction, and neural fibrosis induced by a volitional repetitive task. Pain.

Carro et al. (2016). Deep gluteal space problems: piriformis syndrome, ischiofemoral impingement and sciatic nerve release. Muscles Ligaments Tendons J. (OPEN ACCESS)

Cheatham et al. (2013). Meralgia paresthetica: a review of the literature. Int J Sports Phys Ther.

Chimenti et al. (2018). A Mechanism-Based Approach to Physical Therapist Management of Pain. Phys Ther.

Cholok et al. (2017). Traumatic muscle fibrosis: From pathway to prevention. J Trauma Acute Care Surg.

Cohen & Mao. (2014). Neuropathic pain: mechanisms and their clinical implications. BMJ.

Courtney et al. (2017). Mechanisms of chronic pain - key considerations for appropriate physical therapy management. J Man Manip Ther.

Festen-Schrier & Amadio (2018). The biomechanics of subsynovial connective tissue in health and its role in carpal tunnel syndrome. J Electromyogr Kinesiol.

Fisher et al. (2015). Increased CCN2, substance P and tissue fibrosis are associated with sensorimotor declines in a rat model of repetitive overuse injury. J Cell Commun Signal.

Greening et al. (2018). Evidence for Increased Magnetic Resonance Imaging Signal Intensity and Morphological Changes in the Brachial Plexus and Median Nerves of Patients With Chronic Arm and Neck Pain Following Whiplash Injury. J Orthop Sports Phys Ther.

Isu et al. (2018). Superior and Middle Cluneal Nerve Entrapment as a Cause of Low Back Pain. Neurospine.

Ji et al. (2018). Neuroinflammation and Central Sensitization in Chronic and Widespread Pain. Anesthesiology.

Ji et al. (2016). Pain regulation by non-neuronal cells and inflammation. Science.

Kim et al. (2017). Low back pain due to middle cluneal nerve entrapment neuropathy. Eur Spine J.

Klingler et al. (2014). Clinical Relevance of Fascial Tissue and Dysfunctions. Current Pain and Headache Reports.

Kwon et al. (2018). Anatomical analysis of the distribution patterns of occipital cutaneous nerves and the clinical implications for pain management. J Pain Res.

Hangge et al. (2018). Quadrilateral Space Syndrome: Diagnosis and Clinical Management. J Clin Med.

Latef et al. (2018). Injury of the Radial Nerve in the Arm: A Review. Cureus.

Mackinnon SE. (2002). Pathophysiology of nerve compression. Hand Clin.

Martin et al. (2017). Nerve entrapment in the hip region. Int J Sports Phys Ther.

Muir B. (2017). Dorsal scapular nerve neuropathy: a narrative review of the literature. J Can Chiropr Assoc.

Olivo, R. & Tsao, B. (2017). Peripheral Nerve Injuries in Sport. Neurol Clin.

Paraskevas et al. (2014). Fascial entrapment of the sural nerve and its clinical relevance. Anatomy & Cell Biology.

Porr et al. (2013). Entrapment of the saphenous nerve at the adductor canal affecting the infrapatellar branch - a report on two cases. J Can Chiropr Assoc.

Saban et al. (2014). Deep massage to posterior calf muscles in combination with neural mobilization exercises as a treatment for heel pain: a pilot randomized clinical trial. Man Ther.

Schmid et al. (2018). Entrapment Neuropathies: Challenging Common Beliefs With Novel Evidence. J Orthop Sports Phys Ther.

Schmid et al. (2013). Reappraising entrapment neuropathies--mechanisms, diagnosis and management. Man Ther.

Schmid et al. (2009). Reliability of clinical tests to evaluate nerve function and mechanosensitivity of the upper limb peripheral nervous system. BMC Musculoskeletal Disorders. (OPEN ACCESS)

Stecco et al. (2019). Fascial entrapment neuropathy. Clin Anat.

Szikszay et al. (2017). In vivo effects of limb movement on nerve stretch, strain, and tension: A systematic review. J Back Musculoskelet Rehabil.

Thompson & Usichenko (2018). Pain in the hand caused by a previously undescribed mechanism with possible relevance for understanding regional pain. Scand J Pain.

Triplett et al. (2018). Compressive Lateral Femoral Cutaneous Neuropathy Secondary to Sartorius Muscle Fibrosis. JAMA Neurol.

Wolny et al. (2017). Efficacy of Manual Therapy Including Neurodynamic Techniques for the Treatment of Carpal Tunnel Syndrome: A Randomized Controlled Trial. J Manipulative Physiol Ther.

Wolny & Linek (2018). Is manual therapy based on neurodynamic techniques effective in the treatment of carpal tunnel syndrome? A randomized controlled trial. Clin Rehabil.

Zhu et al. (2018). Neural Mobilization Attenuates Mechanical Allodynia and Decreases Proinflammatory Cytokine Concentrations in Rats With Painful Diabetic Neuropathy. Phys Ther.

Zügel et al. (2018). Fascial tissue research in sports medicine: from molecules to tissue adaptation, injury and diagnostics. Br J Sports Med.