Effects of Neural Mobilization Added to Conventional Physiotherapy in Chronic Neck Pain

Background Chronic neck pain is a highly prevalent musculoskeletal condition and represents a substantial global health burden. Beyond persistent pain, it may lead to restricted cervical mobility, functional limitations, reduced work capacity, and disability, thereby adversely affecting health-related quality of life and generating considerable socioeconomic costs [1, 2].

The multifactorial nature of chronic neck pain reflects the complex interaction of biological, psychological, and social factors, including previous musculoskeletal disorders, physical inactivity, prolonged computer use, occupational demands, psychological stress, and sleep disturbances [2]. Given its high prevalence and substantial functional consequences, the identification of effective and clinically applicable rehabilitation strategies remains an important priority.

Current clinical management of chronic neck pain increasingly emphasizes active and multimodal approaches. Exercise therapy, including strengthening, mobility, motor control, and endurance exercises, together with patient education and promotion of physical activity, constitutes the foundation of contemporary rehabilitation [3]. Manual therapy and selected physical modalities may also be incorporated according to individual clinical presentation. However, despite these approaches, a proportion of patients continue to experience persistent pain and functional limitations. In such individuals, altered neural mechanosensitivity and impaired mechanical interaction between neural tissues and their surrounding interfaces may contribute to symptom persistence. This has increased interest in interventions that specifically address the neurodynamic component of musculoskeletal disorders.

Neural mobilization is a manual therapy approach based on neurodynamic principles and is designed to influence the mechanical and physiological behavior of the peripheral nervous system. By applying controlled movements to neural tissues and their surrounding interfaces, neural mobilization may facilitate neural excursion, modify intraneural pressure, influence axoplasmic transport, reduce intraneural edema, and modulate nociceptive processing [4, 5, 6]. These mechanisms provide a plausible rationale for incorporating neural mobilization into the rehabilitation of patients with neck pain, particularly when neural mechanosensitivity contributes to pain and movement-related dysfunction. Importantly, neural mobilization may not necessarily be considered an alternative to conventional physiotherapy but rather as an adjunctive intervention intended to provide an additional therapeutic effect. Previous randomized controlled trials have reported favorable effects of neural mobilization on pain, cervical range of motion, disability, and upper-extremity function, particularly in individuals with cervical radiculopathy or cervicobrachial pain [7, 8, 9].

However, the existing evidence has predominantly focused on patients with clearly defined neural involvement, whereas evidence in individuals with chronic neck pain more broadly remains comparatively limited. Consequently, it remains uncertain whether the benefits observed in radicular conditions can be generalized to patients with chronic nonspecific neck pain. Furthermore, previous studies have frequently emphasized pain, disability, and cervical mobility, whereas upper-extremity functional status has been less consistently examined.

An important gap in the literature, therefore, concerns the incremental value of neural mobilization when added to conventional physiotherapy. Determining whether neural mobilization provides additional benefits beyond those achieved with conventional physiotherapy may provide greater insight into its clinical utility than examining its effects in isolation.

This question is particularly important because neural mobilization may be incorporated as an adjunct within broader physiotherapy programs, making it important to determine whether its addition provides measurable improvements in patient-relevant outcomes. Accordingly, the present randomized controlled trial aimed to determine whether adding neural mobilization to a conventional physiotherapy program improves pain intensity, cervical range of motion, neck-related disability, and upper-extremity function in individuals with chronic neck pain. By comparing an adjunctive neural mobilization approach with conventional physiotherapy alone, this study sought to clarify the potential additional clinical value of neural mobilization in the rehabilitation of chronic neck pain. We hypothesized that participants receiving neural mobilization in addition to conventional physiotherapy would demonstrate greater improvements in pain, cervical mobility, neck-related disability, and upper-extremity function than those receiving conventional physiotherapy alone.

Methods Ethics Statement The study was conducted in accordance with the principles of the Declaration of Helsinki. Ethical approval was obtained from the Non-Interventional Clinical Research Ethics Committee of İstanbul University-Cerrahpaşa (meeting date: 14 May 2025; decision no. 2025/337). Before participation, all participants received verbal and written information regarding the study procedures, potential risks, and potential benefits. Written informed consent was obtained from all participants prior to enrollment.

Study Design and Setting This study was designed as a single-centre, two-arm, parallel-group randomized controlled trial with a 1:1 allocation ratio. Participants with chronic neck pain were recruited from the Physiotherapy and Rehabilitation Unit of a public state hospital in Istanbul, Türkiye. All study procedures were conducted at the same hospital. Participants were recruited between June 2025 and June 2026, and the final post-treatment assessment was completed in June 2026. The study was conducted under the academic and institutional coordination of Istanbul University-Cerrahpaşa, Department of Physiotherapy and Rehabilitation, Faculty of Health Sciences. The study was reported in accordance with the Consolidated Standards of Reporting Trials (CONSORT) 2010 statement (Additional file 1).

Participants Participants were eligible for inclusion if they were aged 18-65 years, had experienced neck pain continuously or recurrently for at least 3 months, were able to understand the study procedures and complete the outcome assessment instruments, and provided written informed consent to participate in the study. Participants were excluded if they had malignancy, pregnancy, advanced osteoporosis, serious neurological disorders such as stroke, multiple sclerosis, or Alzheimer's disease, or a recently repaired peripheral nerve injury.

Randomization and Allocation Participants were randomly allocated to two treatment groups using a sealed-envelope method. The random allocation sequence was generated using a computer-generated randomization procedure. Allocation concealment was maintained using opaque, sequentially numbered, sealed envelopes that were prepared independently before participant enrollment. The envelopes were opened sequentially after eligibility had been confirmed and informed consent had been obtained. The neural mobilization group received conventional physiotherapy plus neural mobilization, whereas the standard treatment group received conventional physiotherapy alone. The allocation sequence was generated by the principal investigator using the Research Randomizer website with simple randomization. Participants were enrolled by the principal investigator, who also implemented the group allocation.

Owing to the nature of the interventions, the participants, the treating physiotherapist, and the outcome assessor were not blinded to group allocation.

Sample Size The sample-size calculation was performed prior to the study using G*Power software (version 3.1.9.4) to determine the minimum number of participants required to achieve sufficient statistical power. Based on a significance level of α=0.05, a high statistical power of 0.95 (1-β), and an effect size of 0.159 extracted from the preliminary data reported by Alansari et al. [10], an a priori power analysis estimated that a total sample size of 44 participants equally allocated into two groups with 22 subjects per group would be statistically necessary to detect significant differences between the intervention and control conditions.

Interventions Both groups received a 4-week treatment program consisting of 12 treatment sessions with three sessions scheduled per week. The conventional physiotherapy program included TENS, therapeutic ultrasound, hot-pack application, and general neck exercises. The NM group received the same conventional treatment with the addition of bilateral neural mobilization of the radial, median, and ulnar nerves.

Conventional Physiotherapy The standard treatment program was administered over 12 sessions during a 4-week period, with three sessions scheduled per week. Each session consisted of transcutaneous electrical nerve stimulation (TENS), therapeutic ultrasound, hot-pack application, and therapeutic neck exercises. TENS was applied for 20 minutes using a conventional sensory-level stimulation protocol. A high-frequency current of approximately 80-100 Hz was used, with a pulse duration of approximately 200-250 μs. The intensity was individually adjusted to produce a strong but comfortable tingling sensation without pain or visible muscle contraction. Two surface electrodes were positioned over the painful cervical/paracervical region. Similar high-frequency, sensory-level TENS parameters have been used in randomized clinical trials involving individuals with chronic neck pain [11].

Therapeutic ultrasound was subsequently applied to the cervical region using a continuous mode to provide a thermal effect. The ultrasound intensity was set at approximately 1.5 W/cm² and applied for 8-10 minutes over the symptomatic cervical/paracervical area. These parameters are consistent with previous randomized studies of conventional treatment in individuals with chronic neck pain [12, 13]. A hot pack was then applied to the cervical and upper trapezius regions for 20 minutes. The hot pack was wrapped in several layers of towels and applied in a manner that provided comfortable therapeutic heating while avoiding excessive heat or skin irritation. Hot-pack application for approximately 20 minutes to the cervical/paracervical region has also been used in previous clinical trials of chronic neck pain [13]. The therapeutic exercise program consisted of active cervical range-of-motion and isometric strengthening exercises targeting the cervical flexor, extensor, lateral flexor, and rotator muscle groups. Participants performed 10 repetitions of each movement, with approximately 5 seconds of isometric contraction for strengthening exercises. Exercises were performed within a comfortable, symptom-limited range and were progressed according to the participant's tolerance. Similar cervical isometric exercise protocols involving 5-second contractions and 10 repetitions have been reported in randomized trials of chronic neck pain [14]. The same conventional physiotherapy protocol was administered to participants in both treatment groups. The neural mobilization group additionally received the predefined neural mobilization protocol, whereas the standard treatment group received conventional physiotherapy alone.

Neural Mobilization Participants allocated to the NM group received additional bilateral neural mobilization targeting the radial, median, and ulnar nerves. The intervention was based on established neurodynamic mobilization principles and was applied using a sustained tensioning technique rather than a repetitive sliding technique. This classification was based on the use of a progressively loaded neural position that was maintained for a defined period, rather than alternating proximal and distal movements to produce reciprocal loading and unloading of the nerve. Similar tensioning approaches have been described in clinical studies investigating neurodynamic mobilization in patients with cervicobrachial pain and cervical radiculopathy [7, 15].

For each nerve, the participant was positioned in supine lying and the relevant upper-limb joints were placed sequentially to reproduce the corresponding neurodynamic position (Figure 1). The radial nerve technique was performed with the wrist, thumb, and index finger positioned in flexion, the elbow in extension, and the shoulder depressed. Contralateral cervical lateral flexion was used to increase neural loading. The median nerve technique was performed with the shoulder depressed and positioned at approximately 90° of abduction and external rotation, with the forearm supinated and the elbow, wrist, and fingers extended. Contralateral cervical lateral flexion was used to regulate neural loading. For the ulnar nerve, the shoulder was positioned in depression, abduction, and external rotation, with the elbow flexed, forearm pronated, and wrist extended with radial deviation. The head was positioned in contralateral lateral flexion and rotation to regulate neural loading. The neural mobilization procedures were performed bilaterally for the radial, median, and ulnar nerves. For each nerve, the standardized neural position was maintained for 10 seconds and repeated 10 times on each side. The intensity of neural loading was individually adjusted according to the participant's tolerance. The technique was performed without provoking excessive or persistent pain, paresthesia, or other adverse neurological symptoms. The total additional treatment duration was approximately 10-15 minutes per session. Previous neurodynamic mobilization studies have used predefined neural loading procedures and symptom-limited application [4, 16].

Figure 1. Neural mobilization techniques applied in the NM group: (a) radial nerve, (b) median nerve, and (c) ulnar nerve. Each position was maintained for 10 seconds and repeated 10 times bilaterally.

All NM procedures were performed by a physiotherapist experienced in manual and neurodynamic therapy. Before the intervention period, the therapist reviewed the standardized intervention protocol, including participant positioning, sequence of joint movements, application of cervical lateral flexion, duration of each repetition, and criteria for modifying or discontinuing the technique. To improve intervention fidelity, the same therapist administered the neural mobilization intervention to all participants in the NM group, and the predefined protocol was followed consistently throughout the treatment period. Treatment sessions were documented using a standardized intervention checklist, including the treated nerve, number of repetitions, duration of each application, and participant tolerance.

Outcome Measures Outcome assessments were performed immediately before the first treatment session and after completion of the 12th treatment session. Pain, cervical range of motion, neck-related disability, upper extremity function, and neurodynamic responses were assessed.

The primary outcomes were activity-related pain, resting pain, and night-time pain, all assessed using the Visual Analogue Scale (VAS). These three pain measures were considered equally important primary outcomes.

Secondary outcomes included cervical range of motion, neck-related disability, and upper-extremity function. Neurodynamic responses were evaluated as exploratory outcomes.

Pain Intensity Pain intensity was assessed using the Visual Analogue Scale (VAS). Activity-related, night-time, and resting pain were recorded. The VAS was scored from 0 to 10, with 0 representing no pain and 10 representing the worst possible pain [17, 18].

Cervical Range of Motion Active cervical flexion, extension, right and left lateral flexion, and right and left rotation were assessed using goniometric measurements while participants were seated. Measurements were recorded in degrees [19].

Neck Disability Index Neck-related disability was assessed using the Neck Disability Index (NDI). The NDI consists of 10 items addressing pain and limitations in activities of daily living, including personal care, lifting, reading, headache, concentration, work, driving, sleep, and recreation. Each item is scored from 0 to 5, yielding a total score of 0-50, with higher scores indicating greater disability [20, 21].

Upper Extremity Function Upper extremity function was assessed using the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire. The DASH consists of 30 items assessing symptoms and functional limitations related to the upper extremity. Scores range from 0 to 100, with higher scores indicating greater disability [22, 23].

Upper-Limb Neurodynamic Testing Upper limb neurodynamic tests (ULNTs) targeting the median, radial, and ulnar nerves were performed before the first treatment session and after the 12th treatment session. The tests were conducted with the participant in the supine position using predefined upper-limb positioning procedures based on established neurodynamic testing principles [24]. The relevant joints were progressively positioned to increase neural loading, and symptom responses were assessed during the test. Participants were instructed to report the onset of any familiar pain, stretching sensation, tingling, or numbness during the test [24, 25]. Following symptom reproduction, structural differentiation was performed by applying a sensitizing movement at a distant anatomical site, particularly contralateral cervical lateral flexion, to determine whether the reported symptoms changed. The presence or absence of symptom reproduction and the type of symptoms reported were recorded [24, 25, 26].

For each upper-limb neurodynamic test, the presence or absence of four predefined sensory responses pain, stretching sensation, tingling, and numbness was recorded. The median, radial, and ulnar nerves were assessed bilaterally. The type and occurrence of sensory responses elicited during each neurodynamic test were documented separately for each nerve and side. This symptom-based recording procedure is consistent with previous studies in which sensory responses during upper-limb neurodynamic testing were documented according to their nature, including pain, stretching, tingling, and numbness. [24].

This approach is consistent with established methods for interpreting upper limb neurodynamic tests, in which symptom reproduction together with structural differentiation is used to identify a neurodynamic response. The median, radial, and ulnar nerve tests were performed using predefined positioning procedures. For the median nerve, shoulder depression and abduction, external rotation, forearm supination, wrist and finger extension, and elbow extension were progressively introduced. For the radial nerve, shoulder depression, elbow extension, shoulder internal rotation, forearm pronation, wrist and finger flexion, and shoulder abduction were progressively applied. For the ulnar nerve, wrist and finger extension, forearm pronation, elbow flexion, shoulder external rotation, shoulder depression, and shoulder abduction were progressively introduced. The sequence was adjusted according to the participant's tolerance, and excessive or persistent symptoms were avoided [24].

Neurodynamic testing was performed by the same trained physiotherapist at both assessment time points to minimize inter-examiner variability. The examiner followed the same testing sequence and standardized positioning procedures at baseline and post-intervention assessment.

Statistical Analysis All statistical analyses were performed using [IBM SPSS Statistics, version 21.0; IBM Corp., Armonk, NY, USA]. Continuous variables were assessed for distributional characteristics using visual inspection of histograms and Q-Q plots and the Shapiro-Wilk test. Continuous variables are presented as mean ± standard deviation (SD), whereas categorical variables are presented as frequencies and percentages. Baseline characteristics were compared between the NM and STD groups using the independent-samples t test or the Mann-Whitney U test, as appropriate for the distribution of the data. Categorical variables were compared using the chi-square test or Fisher's exact test when expected cell frequencies were small. For the primary and secondary clinical outcomes, treatment effects were evaluated using treatment group (NM vs. STD), time (baseline vs. post-treatment), and the group × time interaction as fixed effects. Estimated mean changes and their corresponding 95% confidence intervals (CIs) were reported. For individual neurodynamic test-level changes, pre- to post-treatment transitions were examined descriptively. Within-group changes in dichotomous test positivity were assessed using the exact McNemar test because of the small cell counts. Between-group comparisons of individual test-level transitions were not performed when cell frequencies were insufficient for reliable estimation. All statistical tests were two-sided, and a p value \<0.05 was considered statistically significant. Given the exploratory nature of the neurodynamic analyses, these findings were interpreted cautiously and considered hypothesis-generating. No imputation was performed for values identified as invalid or erroneous during data-quality screening; such observations were treated as missing in the relevant analyses.

Use of generative artificial intelligence ChatGPT (OpenAI) was used for limited language editing. The authors reviewed the final manuscript and take responsibility for its content.