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Neurodynamics
Abstract
Mobilisation of the nervous system is an approach to physical treatment of pain. The method relies on influencing pain physiology via mechanical treatment of neural tissues and the non-neural structures surrounding the nervous system. Previous descriptions of this method have not clarified the relevant mechanics and physiology, including interactions between these two components. To address this, a concept of neurodynamics is described.
The body presents the nervous system with a mechanical interface via the musculoskeletal system. With movement, the musculoskeletal system exerts non-uniform stresses and movement in neural tissues, depending on the local anatomical and mechanical characteristics and the pattern of body movement. This activates an array of mechanical and physiological responses in neural tissues. These responses include neural sliding, pressurisation, elongation, tension and changes in intraneural microcirculation, axonal transport and impulse traffic.
Because many events occur with body movement, in addition to tension, the term ‘neural tension' is incomplete and requires expansion to include both mechanical and physiological mechanisms. ‘Neural tension tests’ may be better described as ‘neurodynamic tests'. Pathomechanics and pathophysiology in neural tissues and their neighbouring structures may be regarded as pathodynamics.
... Building on Shacklock's idea, the argument posits that treating the nervous system with manual therapy may be a compelling pain management strategy [Shacklock]. This therapy focuses on neural tissues and the structures surrounding the nervous system, including muscles, fascia, and connective tissues 6 . ...
... Neural mobilization (NM) techniques are utilized for the diagnosis and treatment of the mechanical and physiological properties of the PNS 6 . NM techniques are centered on manual manipulations and exercises to restore homeostasis within and around the nervous system 7 . ...
... In contrast, a separate joint movement occurs that reduces nerve tension. The neurodynamic tensioning variant is described as the simultaneous movement of two joints, where one movement loads the nervous system while the other joint's movement further increases the load tension on the nervous system 6,8 . ...
Benefits of neural mobilization (NM) have been described in musculoskeletal patients. The effects of NM on balance appear to be unclear in research, and no studies have tested the possible effects of NM on plantar pressures. Eighteen subjects were evaluated pre and post bilateral gliding of the sciatic nerve and its branches posterior tibial nerve, lateral dorsocutaneous, medial and intermediate dorsocutaneous nerves. Static variables of the plantar footprint and stabilometric variables were measured in a pre-post study. We found no differences in plantar pressure variables, Rearfoot maximum pressure (p = 0.376), Rearfoot medium pressure (p = 0.106), Rearfoot surface (p = 0.896), Midfoot maximum pressure (p = 0.975), Midfoot medium pressure (p = 0.950), Midfoot surface (p = 0.470) Forefoot maximum pressure (p = 0.559), Forefoot medium pressure(p = 0.481), Forefoot surface (p = 0.234), and stabilometric variables either, X-Displacement eyes-open (p = 0.086), Y-Displacement eyes-open (p = 0.544), Surface eyes-open (p = 0.411), Medium speed latero-lateral displacement eyes-open (p = 0.613), Medium speed anteroposterior displacement eyes-open (p = 0.442), X Displacement eyes-closed (p = 0.126), Y-Displacement eyes-closed (p = 0.077), Surface eyes-closed (p = 0.502), Medium speed latero-lateral displacement eyes-closed (p = 0.956), Medium speed anteroposterior displacement eyes-closed (p = 0.349). All variables don´t have significant differences however the measurements had a high reliability with at least an ICC of 0.769. NM doesn´t change plantar pressures or improve balance in healthy non-athletes subjects. NCT05190900.
... Applying tensile forces, a form of mechanical loading, is essential for maintaining homeostasis in the nervous system [6,7]. Both techniques involve specific neuromobilization maneuvers that stimulate the nervous system [1,[8][9][10]. Research indicates that NDTs can affect intraneural circulation and axoplasmic flow, which may influence the conduction of nerve impulses [3,10,11]. ...
... Neurodynamic techniques (NDTs) are manual therapy techniques that focus on enhancing the mechanical function and mobility of peripheral nerves [1,2]. This is achieved by optimizing movement and reducing nerve tension within the nervous system and surrounding tissues [3,4]). ...
... Additionally, the sacral block and fixation belt were used to standardize participant positioning and minimize any potential movement during the interventions that could otherwise influence the outcomes. Sacral stability was achieved by using a sacral block and fixation belt to maintain the same knee extension [1]. These tools are essential for maintaining consistency across participants, thereby ensuring the reliability of the data collected. ...
Objective: To investigate the effect of slider and tensioner neurodynamic techniques (NDTs) on the sympathetic nervous system (SNS) activity, aiming to identify which technique more effectively modulates autonomic responses in asymptomatic individuals. Materials and Methods: In this double-blind controlled trial, a total of 90 healthy participants were randomly allocated into three groups: slider, tensioner, and control. Skin conductance (SC) was continuously monitored throughout the entire 20 min experiment, while body temperature and blood pressure were measured pre- and post-intervention. Results: The SC levels significantly increased in both the slider and tensioner groups compared to the control group during the intervention and end rest period on the left leg (slider vs. control: p < 0.001, d = 1.20; tensioner vs. control: p < 0.001, d = 1.64) and on the right leg (slider vs. control: p < 0.001, d = 1.47; tensioner vs. control: p < 0.001, d = 0.73). There were no significant differences between the two NDTs on the left (p < 0.13, d = 0.89) and right legs (p < 1.00, d = 0.36). The body temperature of the slider group showed a significant increase compared to both the control group (p < 0.001, d = 0.95) and the tensioner group (p < 0.001, d = 1.48). There were no significant differences between the groups in systolic (p = 0.95) or diastolic blood pressure (p = 0.06). There were no side-specific effects on SNS activity between the left and right legs (p < 0.019) during all intervention phases. Conclusions: Significant sympathoexcitatory responses were elicited by both slider and tensioner NDTs in asymptomatic participants, demonstrating their efficacy in modulating the SNS. The differences between the two techniques were not statistically significant; however, the tensioner NDT showed a slightly more pronounced effect, suggesting that the tensioner NDT can be considered superior in terms of overall SNS effect. These findings indicate that both techniques may have the potential to enhance autonomic regulation in clinical practice; however, the tensioner NDT may be more effective. The consistent responses across participants highlight the systemic benefits of NDTs, providing a foundation for further research into their application in symptomatic populations. This study contributes to evidence-based practice by providing baseline data that support the development of theoretical frameworks and aid in clinical decision-making.
... Symptom reduction may result from increased sliding of the nerve and associated tissues, leading to increased nerve mobility and the mobilization of intraneural fluid [19]. Furthermore, Shacklock et al. [20] demonstrated the potential of NTs to enhance blood flow and nerve conduction. Previously literature has demonstrated that NTs can reduce pain and improve knee range of motion. ...
Background and Objectives: Knee osteoarthritis (KO) stands as the third leading cause of disability among the elderly, causing pain, reduced quality of life, and decreased functionality. The objective of this study is to assess the effects of an active neurodynamic technique programme at home on pain, quality of life, and function among individuals with KO. Materials and Methods: Thirty-five participants (69.7% women) aged ≥50 years with KO (Kellgren–Lawrence grades I–II) performed a femoral nerve mobilization programme at home for 6–8 weeks (20 repetitions per day). Pain intensity, using the numerical rating scale (NRS), pressure pain thresholds (PPTs), central sensitization inventory (CSI), temporal assessment, pain modulation, Knee Injury and Osteoarthritis Outcome Score (KOOS), and the 12-item Short Form Survey questionnaire (SF-12) were collected before, after the intervention, and at one, three, six, and twelve months. Results: Participants improved significantly in pain (p < 0.05), with the improvement maintained throughout the follow-up in the NRS and for at least one month in the PPT. There were also statistically significant (p < 0.05) improvements in all subscales of the KOOS, which were maintained throughout the follow-up. Improvements were also found in the CSI and CPM. Conclusions: A home-based active neurodynamic programme for the femoral nerve has been demonstrated to yield positive effects on pain and function in patients with KO.
Diabetic peripheral neuropathy (DPN) primarily affects soft tissue structures such as the transverse arch of the foot, the tibialis anterior, tibialis posterior, and peroneus longus muscles. Neuromuscular taping (NMT), nerve mobilization, and nerve massage are examples of nerve-targeted therapies that show promise in reducing DPN symptoms. Nerve mobilization improves intrafascicular gliding by addressing compartment syndrome, fibrosis, and adhesions within the nerve, while nerve massage quickly reduces accumulated fluid. On the other hand, NMT stimulates peripheral nerve endings, facilitating mechanoreceptors and thereby promoting sensorimotor and proprioceptive feedback mechanisms.
In peripheral nerve surgery, the term “gap” means the distance between the two stumps of a transected peripheral nerve without further specification. The factors that contribute to the formation of a gap are analyzed in this paper. It becomes clear that the gap formed by a true nerve defect has a different meaning than a gap formed by elastic retraction. The final length of a particular nerve gap in an extremity is decisively influenced by the joint position. Therefore, the question arises regarding how a nerve adapts to the length difference during limb motion, which can be estimated for the median nerve during flexion and extension of the elbow joint with approximately 10 cm in an adult patient.
Three mechanisms play an important role: (1) true elongation of the length of the nerve in the relaxed state against elastic forces; (2) movement of the nerve trunk in the longitudinal direction; and (3) increase and decrease of the tissue relaxation at the level of the nerve trunk (relaxed course) and the nerve fibers (change in the undulated course). The efficiency of this mechanism partially depends on the ability of the nerve to move against the surrounding tissue. This ability is provided by the loose connective tissue around the nerve (adventitia, conjunctiva nervorum, perineurium). Only if this movement is possible, traction forces to elongate the nerve are distributed over the whole length of the nerve and are kept minimal for each particular segment. Adhesions of the nerve trunk at the site of repair prevent an equal distribution of forces and cause an unfavorable rise of traction forces at certain segments, according to the anatomic site. True elongation of the nerve, therefore, has only a limited application in overcoming a gap. Alternatives are rerouting, limb-shortening, and nerve-grafting. Today, the most reliable technique is the use of autologous cutaneous nerve segments as free nerve grafts. Advantages and disadvantages of “vascularized” nerve grafts are discussed. The use of neuromatous neurotization to overcome a gap is still in an experimental state.
Twenty-four fresh cadavers were employed to study the vertebral canal and its contents during relative displacement ranging from hyperflexion to hyperextension. Changes in position were visualized by interpedicular bony landmarks associated with neuromeningeal markers positioned after laminectomy. The length of the vertebral canal increased by 5-9 cm in the transition from hyperextension to hyperflexion, thereby necessitating neuromeningeal adaptation. During hyperflexion the degree of neuromeningeal displacement varies with the level of the spinal column but converges toward the two regions of maximum mobility, usually C6 and L4. These movements produce stretching that is particularly forceful at three points: the C6 and L4 myelomeres and the roots of the cauda equina distal to the 4th lumbar roots.
An outline is given of the possible effect passive movement has on pathological conditions involving cervical nerve roots in order to cause a resolution of the condition. Techniques for the treatment of arm pain conditions such as Repetitive Strain Injury (RSI), which are accompanied by signs of abnormal brachial plexus tension, are described. The techniques are outlined in order to give the clinician further insight into an understanding of cervical nerve root conditions and an increased range of treatment choice.
The functional anatomy of the nervous system includes mechanisms to allow adaption to body movements. Injury or impairment of these mechanisms may lead to symptoms. Clinicians using tension tests as part of assessment and treatment have noted that altered nervous system movement and extensibility is a very frequent finding in many disorders. This paper describes a new model for assessment and treatment of mechanical disorders of the nervous system that is based on clinical observations and interpretations of anatomical, biomechanical and pathological literature. A broad approach is outlined which provides an insight into the possible mechanisms by which the nervous system can be responsible for symptom production. The concepts of intraneural and extraneural pathology are put forward and related to assessment and treatment.