Neural Mobilization: A Conceptual Framework
Neural mobilization is a multidimensional treatment approach that has gained popularity because it is effective, and easy to implement. These maneuvers can be performed in a passive manner where a therapist guides the client through a movement pattern, it can also be carried out as part of a self-care program that clients perform on their own. Clinicians may be familiar with terms such as nerve gliding, nerve flossing, sliders and tensioners. These names describe similar approaches, and all these techniques fall under the umbrella of neural mobilization – a gentle form of manual therapy that aims to assess and address irritated peripheral nerves.
Pathophysiology: Sensitivities of Axons Exposed to a Pathological Environment
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 (Bove et al., 2019). This then triggers the release of pro-inflammatory substances (calcitonin gene-related peptide and substance P) from the nerve. This by product 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 (Matsuda et al., 2019).
Examination: Clinical Sensory Testing Can Be Used to Assess for Increased Sensitivity of the Nervous System
If there is an irritated peripheral nerve, clinical sensory testing can be used to assess for areas of hypersensitivity. In addition to orthopedic testing this could involve palpation (neural and non-neural structures). If a hypersensitive peripheral nerve has been identified, a treatment plan is then implemented based on patient-specific assessment findings and patient tolerance.
FXNL: How Do Nerves Become Hypersensitive?
The responses to neural mobilization are complex and multifactorial – physiological and psychological factors interplay in a complex manner. Systematic reviews have shown that neural mobilization combined with multimodal care can improve symptoms, decrease disability and improve function for patients who suffer from peripheral nerve entrapment (Basson et al., 2017).
The biopsychosocial model provides a practical framework for investigating the complex interplay between manual therapy and clinical outcomes. Based on this, the investigation into mechanisms of action should extend beyond local tissue changes and include peripheral and central endogenous pain modulation (Bialosky et al., 2018).
Neural mobilization has a modulatory effect on peripheral and central processes via input from large sensory neurons that prevents the spinal cord from amplifying the nociceptive signal. This anti-nociceptive effect of massage therapy can help ease discomfort in patients who suffer from peripheral nerve entrapments.
Neural mobilization may also involve specific soft tissue treatment to optimize the ability of mechanical interfaces to glide relative to the neural structure. The application of appropriate shear force and pressure impart a mechanical stimulus that may attenuate tissue levels of fibrosis and TGF-β1 (Bove et al., 2016; Bove et al., 2019). Furthermore, passive stretching may help diminish intraneural edema and/or pressure by mobilizing the peripheral nerve as well as associated vascular structures (Boudier-Revéret et al., 2017; Gilbert et al., 2015).
Nerves, Knowledge and Theratube With David Butler
In terms of research evidence neural mobilization has been shown to be particularly helpful for common forms of back, neck, leg and foot pain (Basson et al., 2017). An observed favorable outcome may be explained by overlapping mechanisms in the periphery, spinal cord, and brain, including but not limited to affective touch, contextual factors, neurological factors, and mechanical factors.
Nerves can be exposed to mechanical or chemical irritants at different anatomical points. Gently stretching the muscles, neurovascular structures, and investing fascia activates endogenous pain modulating systems that help to mitigate the transition, amplification and development of peripheral neuropathies and chronic pain.
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