Effects of Adding a Neurodynamic Mobilization to Motor Control Training in Patients With Lumbar Radiculopathy Due to Disc Herniation

A Randomized Clinical Trial

Abstract

Objective 

The aim of the study was to investigate the effects of the inclusion of neural mobilization into a motor control exercise program on pain, related disability, neuropathic symptoms, straight leg raise, and pressure pain threshold in lumbar radiculopathy.

Design 

This is a randomized clinical trial.

Methods 

Individuals with low back pain, with confirmed disc herniation, and lumbar radiculopathy were randomly assigned to receive eight sessions of either neurodynamic mobilization plus motor control exercises (n = 16) or motor control exercises alone (n = 16). Outcomes included pain, disability, neuropathic symptoms, straight leg raise, and pressure pain threshold at baseline, after four visits, after eight visits, and after 2 mos.

Results 

There were no between-groups differences for pain, related disability, or pressure pain threshold at any follow-up period because both groups get similar and large improvements. Patients assigned to the neurodynamic program group experienced better improvements in neuropathic symptoms and the straight leg raise compared with the motor control exercise group (P < 0.01).

Conclusions 

The addition of neurodynamic mobilization to a motor control exercise program leads to reductions in neuropathic symptoms and mechanical sensitivity (straight leg raise) but did not result in greater changes of pain, related disability, or pressure pain threshold over motor control exercises program alone in subjects with lumbar radiculopathy. Future trials are needed to further confirm these findings because between-groups differences did not reach clinically relevance.

What Is Known

• Motor control exercises are effective for the management of low back pain. Some evidence supports the use of neural mobilization in low back pain, but its evidence for radicular pain is poor. We do not know whether combined interventions would lead to better outcomes.

What Is New

• The addition of neurodynamic mobilization to a motor control exercise program leads to some reduction in neuropathic symptoms and mechanical sensitivity but did not result in greater changes of pain, related disability, or pressure pain sensitivity over the application of motor control exercises program alone in subjects with lumbar radiculopathy.

Low back pain (LBP) is a common condition, resulting in a significant impact on the patient in terms of pain and disability. The costs associated with LBP are increasing exponentially.¹ In addition, many individuals with LBP also experience the consequence of a disk herniation, for example, radiating pain and radicular symptoms, which may result in lower limb symptoms, such as radiculopathy.² Lumbar radiculopathy may be the result of a herniated lumbar disc, which may irritate a lumbar nerve trunk resulting in intraneural inflammation. A herniated disk could cause lower limb numbness and weakness in addition to pain experienced by the individuals. Unfortunately, lumbar radiculopathy can progress to chronicity resulting in substantial pain, disability, and burden.³

There are several treatment strategies for the management of LBP and lumbar radiculopathy including disc surgery, injections, analgesia, acupuncture, traction, manual therapy, percutaneous discectomy, exercise, and/or orthosis.⁴ Although optimal management strategy for lumbar stenosis, including radiculopathy, remains to be elucidated, current trends are conservative interventions, such as physical therapy.⁵ Moreover, according to an international survey, surgeons around the world indicated one of the assumptions for an operative intervention is the failure of conservative therapy, thereby implying that conservative therapy is the first treatment option.⁶ Surgery is not more effective than physical therapy after 1 yr on pain relief and perceived recovery.^7,8 Many physical therapy treatment options exist, including manual therapies and exercises; however, the best method to decrease pain and improve function in people with LBP and leg pain associated with lumbar radiculopathy is not currently known.⁹

The most recent Cochrane review found moderate- to high-quality evidence supporting the use of motor control exercises for the management of LBP, although no differences were found with other forms of exercise.¹⁰ There also exists evidence supporting the use of manual therapies, such as spinal manipulation or mobilization for the management of LBP.¹¹ However, different manual therapies, for example, soft tissue interventions, spinal manipulation or mobilization, and neural interventions, target different concepts.

A manual therapy technique that may potentially be used for the management of patients with lumbar radiculopathy is neurodynamic mobilization. Neural mobilization includes both slider and tensioner maneuvers. The aim of a nerve slider intervention is to induce a gliding movement of the nerve trunk in relation to their adjacent tissues. The nerve slider technique applies joint movements to the targeted structure proximally while releasing the movement distally, followed by a reverse combination.¹⁰ In the contrary, the aim of a nerve tensioner intervention is to induce tension of a nerve trunk in relation to their adjacent tissues. The nerve tensioner technique applies joint movements to the targeted structure proximally and distally at the same time and in the same direction toward an increase in nerve tension.¹⁰ It has been postulated that if the nervous system (lumbar nerve root) is irritated, the system may present with neural edema, ischemia and fibrosis, leading to further damage resulting in pain and decreased function.^12,13 The underlying mechanisms of neural mobilization interventions include restoration of homeostasis in and around the nerve and reducing intraneural edema through intraneural fluid dispersion in the nerve root and axon.^14–16

Cleland et al.¹⁷ used a neurodynamic mobilization technique to manage a patient with lumbar radiculopathy in which the individual experienced clinically meaningful reductions in pain. However, no high-quality evidence exists in relation to this particular approach individuals with lumbar radiculopathy.¹⁸ A recent meta-analysis reported that neural mobilization is effective for improving pain and disability in individuals with LBP, but the evidence for the use of neural mobilization for radicular pain was found to be poor.¹⁹ Future trials examining the effects of neural mobilization in people with lumbar radiculopathy are necessary to determine its efficacy.

Therefore, the purpose of this randomized clinical trial was to investigate the effects of the addition of neural mobilization into a motor control exercises program on pain, disability, and pressure sensitivity in individuals with lumbar radiculopathy. Our hypothesis was that subjects with lumbar radiculopathy receiving neural mobilization combined with a motor control exercise program would experience better outcomes than those receiving motor control exercise program alone.

METHODS

Study Design

A randomized, parallel-group, clinical trial was conducted to compare the effects of adding a neurodynamic mobilization into a motor control exercise program on pain intensity, neuropathic symptoms, related disability, straight leg raise test, and pressure pain sensitivity in individuals with lumbar radiculopathy. The study was approved by the institutional review board of Universidad Alcalá de Henares, Spain (CEIM/HU/201531) and the trial was registered (ClinicalTrials.gov: NCT03620864). This trial conforms to CONSORT guidelines and reports the required information accordingly (see Supplemental Checklist, Supplemental Digital Content 1, https://links.lww.com/PHM/A859).

Participants

Between July and October 2018 consecutive patients exhibiting LBP and radiculopathy (lower limb symptoms) were screened for potential eligibility criteria from a local hospital in Madrid, Spain. To be eligible to participate, patients (a) had to be between 18 and 60 yrs old, (b) have a confirmed (via MRI) disc herniation between L4-S1 levels, (c) had to exhibit lumbar radiating pain to one lower limb including the foot, (d) have had pain for at least 3 mos, (e) had increased leg pain on coughing, sneezing, or straining, and (f) had a positive straight leg raise with symptom reproduction between 40 and 70 degrees. All participants received a neurological clinical examination including assessment of muscle weakness, cutaneous sensitivity, and reflexes by an experienced neurologist for evaluating the integrity of the nervous system and avoiding the presence of lumbar radiculopathy. Manual muscle tests were performed to identify the presence of weakness along L4-S1 myotome distribution by using the grading of 0 to 5 (0/5 no movement, 3/5 antigravity, 5/5 normal). Subjects were excluded if they had any of the following criteria: (a) indication for surgical intervention, for example, absence of reflexes, muscle atrophy, and signs compatible with lumbar myelopathy, (b) had a confirmed disc herniation at other lumbar levels, (c) have had any other spinal conditions such as spinal tumors, spondylolisthesis, or cauda equina, (d) had received treatment for this condition by a physical therapist the previous 6 mo, or (e) pregnancy. Participants were also excluded if they exhibited any contraindications to manual therapy or exercise as noted in the patient’s Medical Screening Questionnaire, such as rheumatoid arthritis, osteoporosis, prolonged history of steroid use, severe vascular disease, etc. All subjects signed an informed consent before participation in the study.

All participants provided a detailed history, underwent a physical examination, and completed a number of self-report measures at baseline. The historical items included questions pertaining to the onset of sensory symptoms including pain, pins or needles, the distribution of the symptom, aggravating and easing postures, mechanism of injury, previous treatments, and history of low back or leg pain. These physical examination items were those that are routinely used in the physical therapy examination of the lower limb.

Randomization and Masking

Subjects were randomly assigned to receive either motor control exercises plus neurodynamic mobilization or a motor control exercise program alone. Concealed allocation was performed by an individual not involved in subject’s recruitment using a computer-generated randomized table of numbers created before the beginning of the trial. The group assignment was recorded on an index card. This card was folded in half such that the label with the patient’s group assignment was on the inside of the fold. The folded index card was then placed inside the envelope, and the envelope was sealed. A second therapist blinded to the baseline examination findings opened the envelope and proceeded with treatment according to the group assignment.

Treatment Interventions

All interventions were applied by an experienced physical therapist with more than 10 yrs of experience in the management of patients with lumbar radiculopathy.

Both groups received 8 sessions of a motor control exercise program of 30-min duration for 4 wks, twice a week, following expert recommendations,^20,21 and as previously used by Costa et al.²² On each session, the therapist corrected each subject individually to ensure correct technique and ensured that the participant was confident to perform the exercises alone at home. Participants were asked to perform exercises at home once daily for 20 mins for the 8-wk intervention period. The motor control exercise program consisted of a progression from isolated contraction of the transversus abdominis and/or isolated contraction of the multifidi to combined contraction of both transversus abdominis and multifidi muscles in different positions from supine or prone to bridging or four-point kneeling (Fig. 1). Each participant was progressed on exercises when they have reached an independent activation of the transversus abdominis and multifidus without overactivity of superficial muscles in an individualized manner (visual observation by the therapist). Each exercise was performed for 10 repetitions for 10 secs each as previously described.²² The adherence to the exercise program was collected on each subsequent session in a weekly diary.

FIGURE 1: Monitoring correct contraction of the transversus abdominis (A), multifidi (B), or both combined (C) in different positions (supine, prone, four-point kneeling).

Patients allocated to the neurodynamic group also received a nerve neurodynamic slider intervention targeting the main trunk of the sciatic nerve of the affected side. Previous studies have suggested that nerve slider techniques are associated with larger nerve excursion than nerve tensioner interventions.^23,24 The nerve slider intervention applied in the current study included flexion, adduction and medial rotation (if possible) of the hip, knee extension, and ankle dorsiflexion. From this position, concurrent hip flexion and knee flexion were alternated dynamically with concurrent hip and knee extension (Fig. 2). During the intervention, the therapist alternated the movement combination depending on the tissue resistance and patient’s symptoms. Speed and amplitude of movement were adjusted such that no pain was produced during the technique. The slider intervention was applied for 3 sets of 10 repetitions on each treatment session for 8 wks, and it was applied 5 mins before the motor control exercise program.

FIGURE 2: Nerve slider intervention targeting the sciatic nerve. First, flexion, adduction and medial rotation (if permitted) of the hip, knee extension, and ankle dorsiflexion are applied (A). From this position, concurrent hip flexion and knee flexion (B) are alternated dynamically with concurrent hip and knee extension (C).

Outcome Measures

All outcomes were assessed at baseline, after four treatment sessions (mid follow-up), after the treatment program (immediate follow-up), and 2 mos after the last treatment session (follow-up) by an assessor blinded to the group allocation of the subjects.

The primary outcome was the intensity of lower limb pain symptoms. Participants rated the intensity of their lower limb pain at rest on an 11-point numeric pain rating scale (NPRS) where 0 represents no pain and 10 is the maximum pain.²⁵ Because there is no specific minimum clinically important difference (MCID) for NPRS in individuals experiencing lumbar radiculopathy, we used the MCID established as 2 points for patients with LBP.²⁶ The cutoff of 2 points is usually considered an MCID for chronic pain in general.²⁷

Secondary outcomes included the Self-report Leeds Assessment of Neuropathic Symptoms and Signs Scale (S-LANSS), the Roland-Morris Disability Questionnaire (RMDQ), the straight leg raise test, and pressure pain sensitivity. The S-LANSS is a simple and valid seven-item tool for identifying individuals whose pain is dominated by neuropathic mechanisms.²⁸ Each item is a binary response (yes or no) to the presence of symptoms (five items) or clinical signs (two items). The total score is 24 points and a value of 12 points or higher is indicative of a neuropathic component of pain. In the current trial, the validated Spanish version of the S-LANSS was used.²⁹

The RMDQ is one of the most comprehensively validated outcome measures for LBP.³⁰ To score the RMDQ, the number of items checked by the patient is tallied (yes/no).³¹ If patients indicate that an item is not applicable to them, the item is scored “No,” i.e., the denominator remains. The score ranges from 0 to 24 with higher scores indicative of higher related disability. The MCID for the RMDQ has been reported to range from 2 to 8 points.³² Lauridsen et al.³³ found that the RMDQ also exhibited good responsiveness for patients with leg pain showing a MCID of 5 points.

The straight leg raise test examines the sensitivity of the sciatic nerve. It is performed passively with patients in supine. The clinician lifts the leg while maintaining the knee extended. Reproduction of the patient symptoms between 40 and 70 degrees is considered as indicative of a disc herniation comprising a nerve root. The straight leg raise has shown a sensitivity of 91% and specificity of 26%.³⁴ Neto et al.³⁵ found that changes ranging from 7 to 8 degrees can be considered minimal detectable difference for the straight leg raise test, whereas Dixon and Keating³⁶ reported that intersession measurements need to change by more than 16 degrees to represent a relevant change.

Pressure pain sensitivity was assessed by pressure pain thresholds (PPTs), that is, the minimal amount of pressure applied on a particular point for the pressure sensation to first change to pain.³⁷ A mechanical pressure algometer (Pain Diagnosis and Treatment Inc, New York) was used in this trial to assess PPTs (kilogram per square centimeter) over the common peroneal (where it passes behind the head of the fibula as it winds forward around its neck) and tibial (where it bisects the popliteal fossa, lateral to the popliteal artery) nerve trunks of the affected leg. The reliability of PPT assessment over these nerve trunks has been found to range from moderate to high.³⁸ All participants were instructed to press the switch when the sensation changed from pressure to pain. The mean of three trials was calculated on each point and used for the analysis. A 30-sec resting period was allowed between each measure. The order of assessment was randomized between subjects.

Treatment Adverse Effects

At each session, patients were asked to report any adverse events that they experienced. In the current trial, an adverse event was defined as sequelae of 1-wk duration with symptoms perceived as distressing and unacceptable to the patient and required further treatment.³⁹

Sample Size Determination

The sample size was calculated using Ene 3.0 software (Autonomic University of Barcelona, Spain) and was based on detecting between-groups difference of 2.0 points on a NPRS,^26,27 assuming a standard deviation of 1.4, a two-tailed test, an α level of 0.05, and a desired power (β) of 80%. The estimated desired sample size was calculated to be of 16 subjects per group.

Statistical Analysis

Data were analyzed using the SPSS Version 21.0 (SPSS Inc, Chicago, IL) program. Means, standard deviation, and 95% confidence intervals were calculated for each variable. The Kolmogorov-Smirnov test revealed a normal distribution of all the quantitative data (P > 0.05). Baseline demographic and clinical variables between groups were compared using independent t test for continuous data and χ² tests of independence for categorical data. A mixed-model 4 × 2 analysis of covariance (ANCOVA) with time (before, mid follow-up, immediate follow-up, 2 mos) as the within-subjects factor, group (motor control or motor control plus neurodynamic) as the between-subjects factor, and sex as covariate was used to examine the effects of the interventions on each outcome (ie, pain intensity, S-LANSS, straight leg raise, and PPTs). For each ANCOVA, the hypothesis of interest was the group × time interaction. In general, a P value of less than 0.05 was considered statistically significant, but post hoc analyses were conducted with a Bonferroni test using a corrected α of 0.025 (2 independent samples). The effect size was calculated when the η²_p was significant. To determine the clinical effect sizes, standardized mean score differences (SMDs) were calculated by dividing the mean score differences between groups by the pooled standard deviation. In general, an SMD of 0.2 is considered small, 0.5 moderate, and 0.8 large clinical effect size.

RESULTS

Forty consecutive subjects with symptoms in the lower limb compatible with lumbar radiculopathy were screened for potential eligibility between July and October 2018. Thirty-two patients satisfied all criteria, agreed to participate, and were randomly allocated to the motor control exercises (n = 16) or motor control exercise plus neurodynamic intervention (n = 16) group. The reasons for ineligibility are listed in the flow diagram of patient recruitment and retention (Fig. 3). Baseline features between both groups were similar for all outcomes (Table 1). None of the subjects receiving either intervention reported any adverse events. The adherence to the exercise program was 96% as collected on the weekly diary.

FIGURE 3: Flow diagram of participants throughout the course of the study.

TABLE 1: Baseline demographics and clinical data by treatment assignment*

Pain Intensity

The ANCOVA did not find a significant group × time interaction for lower limb pain (F = 1.269, P = 0.273, η²_p = 0.043): patients receiving motor control exercises program alone or combined with a neurodynamic intervention experienced similar decreases in lower limb pain (Table 2, Fig. 4A). Between-groups effect sizes were small (SMD = 0.2), whereas within-group effect sizes were large for both groups (SMD > 1.25). Sex did not influence the effect in the main analysis (F = 0.895, P = 0.355).

TABLE 2: Evolution of the outcomes by randomized treatment assignment

FIGURE 4: Evolution of leg pain intensity (A), S-LANSS (B), RMDQ (C), and straight leg raise (D) throughout the course of the study stratified by randomized treatment assignment. Data are means (standard error).

Neuropathic Symptomatology (S-LANSS)

The ANCOVA revealed a significant group × time interaction for S-LANSS (F = 8.559, P = 0.008, η²_p = 0.373): patients in the motor control exercise plus neurodynamic intervention group exhibited a greater decrease in the S-LANSS score (suggesting a decrease of neuropathic symptoms) than those in the motor control exercise alone group (Table 2, Fig. 4B). Between-groups effect sizes were large immediately after treatment (SMD = 0.95) and at 2 mos (SMD = 0.75). Sex did not influence the interaction on the S-LANSS (F = 0.211, P = 0.651).

Related Disability (RMDQ)

The results did not reveal a significant group × time interaction for the RMDQ (F = 2.970, P = 0.101, η²_p = 0.023): patients in both groups experienced similar decreases in related disability (Table 2, Fig. 4C). Between-groups effect sizes were small (SMD = 0.18), whereas within-group effect sizes were large for both groups (SMD > 1.15). Sex did not influence the main effect in the analysis (F = 0.202, P = 0.658).

Mechanical Pain Sensitivity (Straight Leg Raise and PPT)

The ANCOVA revealed a significant group × time interaction for the straight leg raise (F = 7.512, P = 0.013, η²_p = 0.220): individuals in the motor control exercise plus neurodynamic intervention group exhibited greater improvements in the straight leg raise test (suggesting a decrease of mechanical sensitivity) than those in the motor control exercise alone group (Table 2, Fig. 4D). Between-groups effect sizes were moderate (SMD = 0.55) after four treatment sessions and large immediately after the treatment (SMD = 1.05) and at 2-mo follow-up (SMD = 0.9). Sex did not influence the main interaction on the straight leg raise (F = 0.994, P = 0.331).

Finally, no significant group × time interactions for changes in PPTs in the tibial (F = 0.582, P = 0.454, η²_p = 0.026) or common peroneal (F = 0.658, P = 0.426, η²_p = 0.029) nerve trunks were observed: patients receiving motor control exercises alone or combined with a neurodynamic intervention experienced similar increases in PPTs (Table 2). Between-groups effect sizes were small (SMD = 0.14), whereas within-group effect sizes were large for both groups (SMD > 1.04). Sex did not influence the interaction effects on PPTs (tibial: F = 0.678, P = 0.420; common peroneal: F = 0.620, P = 0.440).

DISCUSSION

This is the first clinical trial examining the effects of adding nerve neurodynamic mobilization to a program of motor control exercises compared with motor control exercises alone in individuals with lumbar radiculopathy. Our results demonstrated that the addition of nerve mobilizations did not result in a greater change on leg pain, related disability, or PPT over motor control exercises in this population; however, those receiving motor control exercises/neurodynamic mobilizations experienced significantly greater reductions in neuropathic symptoms (S-LANSS) and mechanical sensitivity as measured by the straight leg raise test suggesting that neurodynamic mobilizations may have a greater impact on nerve tissue sensitivity.

Although the exact mechanisms underlying the effects of manual therapies are uncertain,⁴⁰ a number of potential theories exist as to how manual therapies, including neurodynamic nerve mobilizations, might exert their therapeutic effects. It is possible that neurodynamic mobilization may have the ability to alter descending inhibitory pain mechanisms,⁴¹ to modify blood flow to regions in the brain associated with pain,⁴² and reduce activation of supraspinal pain centers.⁴³ However, these mechanisms would be expected to have an impact on patient-centered outcomes, such as pain and disability, which has been identified in studies using neurodynamic treatments for individuals with nerve entrapment of the upper limb, for example, carpal tunnel syndrome.⁴⁴ The fact that no between-groups differences were observed for pain intensity and related disability may be associated to the fact that there is evidence supporting the application of motor control exercises for the management of this population.¹⁰ Both groups obtained significant and large clinical effects, which may support the positive effect of motor control exercises; however, the lack of a control group and the small sample size do not permit us to conclude this.

Participants receiving the neurodynamic intervention experienced large improvements in neuropathic symptoms and the impact on neural sensitivity as assessed by the straight leg raise. It should be noted that between-groups differences at 2-mo follow-up for the straight leg raise (8.8 degrees) surpassed the minimal detectable difference reported by Neto et al.³⁵ but not the cutoff (16 degrees) determined by Dixon and Keating³⁶ supporting a potential, but small, effect of the neurodynamic mobilization in this outcome. In addition, it should be noted that the straight leg raise does not only assess neural sensitivity because it can be also associated with hamstring tightness.

It is also important to note that both groups decreased significantly their S-LANSS scores, although the neurodynamic mobilization groups exhibited a greater and larger decrease. After all treatment sessions, almost all participants in both groups were below the 12-point cutoff that determines the presence of neuropathic symptoms supporting that both interventions may be capable of reducing neuropathic symptoms, although changes were superior when a neurodynamic mobilization was included into the treatment program. Several hypotheses explaining changes in these outcomes can be proposed. For example, a cadaveric study performed on the tibial nerve found that neurodynamic mobilization resulted in dispersion of intraneural fluid,¹⁵ which might assist in a reduction of intraneural edema found in individuals experiencing neural compression.⁴⁵ Another cadaveric study examining a potential impact of simulated neurodynamic mobilization technique on sections of the sciatic nerve also found dispersal of intraneural fluid, which was hypothesized for resulting to decreased intraneural edema and intraneural pressure.¹⁴ However, these hypothesis in people with actual nerve compression requires further research. It is interesting to note that a study comparing nerve and tendon glides to splinting in subjects with carpal tunnel syndrome, a neuropathic condition of the wrist, showed that both interventions resulted in similar reduction on intraneural edema.⁴⁶ However, splinting is not a viable option for individuals with lumbar radiculopathy.

It should also be noted that the effect sizes for changes in the S-LANSS and straight leg raise test were much larger after eight sessions as compared with when measured after just four sessions. It is difficult to determine the dosage (number of treatment sessions) necessary to maximize patient outcomes. The topic of tolerance or a decrease in magnitude of effect over time is an area of discussion. For example, Fernández-de-las-Peñas et al.⁴⁷ found that after receiving consecutive sessions of thoracic manipulation, patients continued to receive added benefit with additional visits. Another study comparing the dose response of spinal manipulation, comparing 0, 6, 12, and 18 sessions, found that 12 sessions of spinal manipulation were best for maximizing changes in pain and disability in individuals with chronic LBP at a 12-wk follow-up.⁴⁸ Therefore, the ideal dose response for neurodynamic mobilizations requires further investigation but from the current results, it seems that eight treatments result in superior outcomes when compared with four treatments.

Study Limitations

Finally, there are several limitations to the current study that should be considered. Only one therapist provided all the techniques at one geographical location. Although this enhances the internal validity, it potentially reduces the generalizability of current findings. Second, we included a relatively small sample size, which could be underpowered to identify a difference on some outcomes. Furthermore, the sample was restricted to patients with disc herniation between L4-S1 level, so we do not know whether these results would be similar in patients with disc problems at other lumbar levels. Similarly, the lack of control for the magnitude (size and spinal cord location) of the disc herniation could limit the results. Finally, we only included a 2-mo follow-up. Future clinical trials should include additional clinicians from different locations, larger sample sizes, and collect outcome measures at long-term follow-up.

CONCLUSIONS

The results of the current trial performed on individuals with LBP, confirmed disc herniation, and radiculopathy, observed that they did not experience greater improvements in pain, function or PPT when they received neurodynamic mobilization in addition to motor control exercises. However, although patients receiving neural mobilizations experienced greater changes in neural mechanosensitivity as measured by the S-LANSS and straight leg raise; these differences were small and probably not clinically relevant. Future clinical trials are needed to further confirm these findings.