The impact of neurodynamic testing on the perception of experimentally induced muscle pain

Straight leg raise versus knee extension angle: which structure limits the test in asymptomatic subjects?

OBJECTIVES

This study aimed to determine if the first onset of symptoms (discomfort) during the straight leg raise (SLR) (hip flexion with an extended knee) and the Knee Extension Angle (KEA) tests (knee extension with 90°of hip flexion) results from nervous or muscular structures in asymptomatic individuals. The secondary objective was to investigate if the gender influences the structure related to the discomfort.

METHODS

This cross-sectional study consisted of a single assessment session during which the structure related to participants' discomfort during the KEA and SLR was identified. For this identification, a structural differentiation (SD) was conducted during both tests using passive mobilization of the cervicothoracic spine in flexion and extension. Changes in participants' discomfort were monitored during the SD to determine whether a change or lack of change was consistent with variations in the load applied to the suspected structures either muscular or neural. If the structure related to the participants' discomfort could not be identified, two additional tests were conducted: the lateral SLR and the Slump test.

RESULTS

One hundred and seventy-eight individuals were included. Median [IQR] age was 21 years [20;23], and 57.3% were female. The structure related to participants' discomfort was similar for the SLR and the KEA (p = 0.451): neural for 72.5% of participants in the SLR and 75.8% in the KEA. Gender only influenced the structure identified in the KEA test, with a significantly higher rate of nerve-related discomfort in females than males and a significantly higher rate of muscle-related discomfort in males (p = 0.002).

CONCLUSION

In asymptomatic individuals, the discomfort induced by the SLR and the KEA tests could be related to either muscular or neural structures. Therefore, structural differentiation is necessary to identify the structure causing the discomfort in both research and clinical practice.

Effect of cervical contralateral lateral flexion on the median nerve and fascia at the wrist - Cadaveric study

BACKGROUND

Neurodynamic tests are an essential aspect of the physical examination of the patient when suspicion of neural involvement exists. A manoeuvre that is hypothesised to move nerves differentially relative to other structures (structural differentiation) has been proposed as a necessary part of neurodynamic testing for differential diagnosis. However, although the specificity of structural differentiation for peripheral nerve over muscle has been demonstrated in some body regions, no study has tested specificity of nerve movement relative to fascia.

OBJECTIVES

The aim of this study was to measure the effect of the cervical contralateral lateral flexion (CCLF) as an structural differentiation manoeuvre for the median nerve compared to fascia (superficial and deep) at the wrist during the upper limb neurodynamic test 1 (ULNT1).

DESIGN

A cross-sectional study was performed in 5 fresh frozen cadavers.

METHODS

Excursion and strain in the fascia (superficial and deep) and the median nerve were measured at the wrist with structural differentiation during the ULNT1. KINOVEA software was used to measure kinematic parameters.

RESULTS

CCLF resulted in significant proximal excursion in the median nerve (p < 0.001*) but not in the strain. CCLF neither produced changes in strain nor excursion in the superficial and deep fascia (p > 0.05).

CONCLUSION

This study showed that CCLF produced significant differential excursion in the median nerve at the wrist compared to the local superficial and deep fascia during the ULNT1. The data support CCLF in mechanical differentiation between nerve and fascia in this area in diagnosis of local sources of wrist pain.

Routine Physical Therapy with and without Neural Mobilization in Chronic Musculoskeletal Neck Disorders with Nerve-Related Symptoms: Systematic Review and Meta-Analysis

No previous study has evaluated the effectiveness of routine physical therapy with and without neural mobilization for patients with chronic musculoskeletal neck disorders and cervical radiculopathy. The objective is to evaluate the effectiveness of routine physical therapy with and without neural mobilization on pain and mobility in patients with chronic musculoskeletal neck disorders and cervical radiculopathy. A systematic review with meta-analysis of randomized clinical trials involving the use of neural mobilization techniques for the treatment of chronic musculoskeletal neck disorders and cervical radiculopathy was conducted. Methodological quality was assessed by the Cochrane Risk of Bias Tool and PEDro scale. Data were pooled and a meta-analysis was performed using a random effects model with Review Manager 5 software. Seven articles were included in our review. Significant differences were found in mobility but not in pain in favor of using routine physical therapy with neural mobilization for the treatment of chronic musculoskeletal neck disorders and cervical radiculopathy. Our results show that routine physical therapy accompanied by neural mobilization is superior for improving mobility in comparison with routine physical therapy alone in patients with musculoskeletal neck disorders and cervical radiculopathy.

Intra- and interindividual reliability of muscle pain induced by an intramuscular injection of hypertonic saline injection into the quadriceps

BACKGROUND

Intramuscular injections of hypertonic saline are commonly used to induce experimental muscle pain, but reliability data on this technique are lacking. This study investigated the intra- and interindividual reliability of pain measures from a hypertonic saline injection into the vastus lateralis.

METHODS

Fourteen healthy participants (6 female) attended three laboratory visits where they received an intramuscular injection of 1 mL hypertonic saline into the vastus lateralis. Changes in pain intensity were recorded on an electronic visual analogue scale, and pain quality was assessed after pain had resolved. Reliability was assessed with the coefficient of variation (CV), minimum detectable change (MDC) and intraclass correlation coefficient (ICC) with 95% CIs.

RESULTS

Mean pain intensity displayed high levels of intraindividual variability (CV = 16.3 [10.5-22.0]%) and 'poor' to 'very good' relative reliability (ICC = 0.71 [0.45-0.88]) but had a MDC of 11 [8-16] au (out of 100). Peak pain intensity exhibited high levels of intraindividual variability (CV = 14.8 [8.8-20.8]%) with 'moderate' to 'excellent' levels of relative reliability (ICC = 0.81 [0.62-0.92]), whereas the MDC was 18 [14-26] au. Measures of pain quality exhibited good reliability. Interindividual variability in pain measures was high (CV > 37%).

CONCLUSIONS

Intramuscular injections of 1 mL of hypertonic saline into the vastus lateralis display substantial levels of interindividual variability, but MDC is below the clinically important changes in pain. This model of experimental pain is suitable for studies involving repeated exposures.

SIGNIFICANCE

Many pain research studies have performed intramuscular injections of hypertonic saline to investigate responses to muscle pain. However, the reliability of this technique is not well established. We examined the pain response over three repeated sessions of a hypertonic saline injection. The pain induced by hypertonic saline has considerable interindividual variability but has largely acceptable intraindividual reliability. Therefore, the injections of hypertonic saline to induce muscle pain are a reliable model of experimental muscle pain.

Patient expectations about a clinical diagnostic test may influence the clinician's test interpretation

BACKGROUND

With medical information widely available, patients often have preconceived ideas regarding diagnostic procedures and management strategies.

OBJECTIVES

To investigate whether expectations, such as beliefs about the source of symptoms and knowledge about diagnostic tests, influence pain perception during a clinical diagnostic test.

DESIGN

Cross-sectional study.

METHODS

Pain was induced by intramuscular hypertonic saline infusion in the thenar muscles. In line with sample size calculations, fifteen participants were included. All participants received identical background information regarding basic median nerve biomechanics and basic concepts of differential diagnosis via mechanical loading of painful structures. Based on different explanations about the origin of their induced pain, half of the participants believed (correctly) they had 'muscle pain' and half believed (incorrectly) they had 'nerve pain'. Pain intensity and size of the painful area were evaluated in five different positions of the median nerve neurodynamic test (ULNT1 _MEDIAN). Data were analysed with two-way analyses of variance.

RESULTS

/findings: Changes in pain in the ULNT1 _MEDIAN positions were different between the 'muscle pain' and 'nerve pain' group (p < 0.001). In line with their expectations, the 'muscle pain' group demonstrated no changes in pain throughout the test (p > 0.38). In contrast, pain intensity (p ≤ 0.003) and size of the painful area (p ≤ 0.03) increased and decreased in the 'nerve pain' group consistent with their expectations and the level of mechanical nerve loading.

CONCLUSION

Pain perception during a clinical diagnostic test may be substantially influenced by pain anticipation. Moreover, pain was more aligned with beliefs and expectations than with the actual pathobiological process.

Acute experimentally-induced pain replicates the distribution but not the quality or behaviour of clinical appendicular musculoskeletal pain. A systematic review

OBJECTIVES

Experimental pain is a commonly used method to draw conclusions about the motor response to clinical musculoskeletal pain. A systematic review was performed to determine if current models of acute experimental pain validly replicate the clinical experience of appendicular musculoskeletal pain with respect to the distribution and quality of pain and the pain response to provocation testing.

METHODS

A structured search of Medline, Scopus and Embase databases was conducted from database inception to August 2020 using the following key terms: "experimental muscle pain" OR "experimental pain" OR "pain induced" OR "induced pain" OR "muscle hyperalgesia" OR ("Pain model" AND "muscle"). Studies in English were included if investigators induced experimental musculoskeletal pain into a limb (including the sacroiliac joint) in humans, and if they measured and reported the distribution of pain, quality of pain or response to a provocation manoeuvre performed passively or actively. Studies were excluded if they involved prolonged or delayed experimental pain, if temporomandibular, orofacial, lumbar, thoracic or cervical spine pain were investigated, if a full text of the study was not available or if they were systematic reviews. Two investigators independently screened each title and abstract and each full text paper to determine inclusion in the review. Disagreements were resolved by consensus with a third investigator.

RESULTS

Data from 57 experimental pain studies were included in this review. Forty-six of these studies reported pain distribution, 41 reported pain quality and six detailed the pain response to provocation testing. Hypertonic saline injection was the most common mechanism used to induce pain with 43 studies employing this method. The next most common methods were capsaicin injection (5 studies) and electrical stimulation, injection of acidic solution and ischaemia with three studies each. The distribution of experimental pain was similar to the area of pain reported in clinical appendicular musculoskeletal conditions. The quality of appendicular musculoskeletal pain was not replicated with the affective component of the McGill Pain Questionnaire consistently lower than that typically reported by musculoskeletal pain patients. The response to provocation testing was rarely investigated following experimental pain induction. Based on the limited available data, the increase in pain experienced in clinical populations during provocative maneuvers was not consistently replicated.

CONCLUSIONS

Current acute experimental pain models replicate the distribution but not the quality of chronic clinical appendicular musculoskeletal pain. Limited evidence also indicates that experimentally induced acute pain does not consistently increase with tests known to provoke pain in patients with appendicular musculoskeletal pain. The results of this review question the validity of conclusions drawn from acute experimental pain studies regarding changes in muscle behaviour in response to pain in the clinical setting.

Effects of neurodynamic treatment on hamstrings flexibility: A systematic review and meta-analysis

OBJECTIVE

To provide detailed information on the effectiveness of neurodynamic treatment on hamstrings flexibility.

METHODS

Systematic review in the following databases: PubMed, Google Scholar, and ScienceDirect. Articles were included if the intervention followed a neurodynamic treatment and the study was a randomized clinical trial including at least one measurement related to hamstrings flexibility. Articles were independently screened for inclusion and data were extracted by two researchers. It was registered in the PROSPERO database (CRD42015020707).

RESULTS

Finally, 6 articles (n = 294 participants) were included. Neurodynamic treatment was compared with no treatment, placebo, and with other manual therapy techniques such as active and passive stretching, muscle inhibition and proprioceptive neuromuscular facilitation. Meta-analysis shows benefits of neurodynamic treatment for knee-extension range of motion (1 trials compared with no intervention, MD = -2.23, 95% CI = -3.02 to -1.44, and 4 trials compared to other techniques, MD = -0.40, 95% CI = -1.09 to 0.29, I² = 81.55%) and passive straight leg raise test measures (2 trials compared with no intervention, MD = 2.26, 95% CI = 1.78 to 2.74, I² = 0%, and 3 trials compared with other techniques MD = 2.26, 95% CI = 1.78 to 2.74, I² = 0%).

CONCLUSIONS

This review and meta-analysis shows the effectiveness of neurodynamic treatment on hamstrings flexibility compared with no intervention and other techniques.

Differential movement of the sciatic nerve and hamstrings during the straight leg raise with ankle dorsiflexion: Implications for diagnosis of neural aspect to hamstring disorders

INTRODUCTION

In hamstrings injuries, sciatic nerve and muscle disorders can coexist. Therefore, differential diagnosis to include or exclude nerve involvement is an important aspect of evaluation. The objective of this paper is to investigate the mechanical behaviour of the sciatic nerve and biceps femoris muscle in the proximal thigh with the ankle dorsiflexion manoeuvre at different degrees of hip flexion during the straight leg raise in cadavers.

MATERIAL AND METHODS

A cross-sectional study was carried out. Linear displacement transducers were inserted into the sciatic nerve and the biceps femoris muscle of 11 lower extremities from 6 fresh cadavers to measure potential strain of both structures during ankle dorsiflexion at 0°, 30°, 60° and 90° of hip flexion during the straight leg raise. Excursion was also measured with a digital calliper.

RESULTS

Ankle dorsiflexion resulted in significant strain and distal excursion of the sciatic nerve at all ranges of hip flexion during the straight leg raise (p < 0.05). In contrast, the ankle movement did not affect the strain in biceps femoris at any position of the hip (p > 0.05).

CONCLUSION

Ankle dorsiflexion at different degrees of hip flexion during the straight leg raise produces changes in the strain and excursion of the sciatic nerve in the upper thigh. In contrast, the biceps femoris muscle at the same location was not affected by ankle movement. These findings show differential behaviour between the nerve and muscle with ankle dorsiflexion at this location that could be used as differential diagnosis in posterior hip pain.

Mobilization of the contralateral limb in Slump position: effects on knee extension in healthy adult subjects

BACKGROUND AND AIM

In the acute phase of neuropathic pain due to nerve root disorders, the neurodynamic approach proposes the mobilization of the contralateral limb to decrease the pain and increase the range of motion in the affected limb. The aim of this study was to evaluate the effect of the contralateral knee mobilization on the ipsilateral knee extension range of motion in Slump position in healthy adult subjects.

METHODS

Thirty-eight healthy subjects underwent a placebo, control and experimental manoeuvres that included a passive contralateral knee mobilization into extension. The knee, hip and cervical angles and distance between glabella and femoral condyle achieved in Slump test position were measured with an optoelectronic motion analysis system before and after each manoeuvre.

RESULTS

Experimental manoeuvre produced a statistically significant increase of the knee extension ROM when compared to the control (p=.017) and placebo (p=.007) manoeuvres. A significant increase of the hip angle and distance between glabella and femoral condyle was detected after the experimental manoeuvres (p<.001), but not after the placebo and control manoeuvres.

CONCLUSIONS

The contralateral mobilization in Slump position increases the ipsilateral knee extension ROM. Further research is required to confirm that the knee increment ROM was due to the neural component.

Comparisons of hamstring flexibility between individuals with and without low back pain: systematic review with meta-analysis

Background: There is no robust evidence on the contribution of reduced hamstring flexibility to the development of low back pain (LBP) in cohort studies.Purpose: To investigate whether individuals with LBP have impaired hamstring flexibility and stiffness and what measures have been used to compare hamstring flexibility and stiffness between individuals with and without LBP.Methods: A systematic literature search was undertaken in PubMed, EMBASE, MEDLINE, CINAHL, SCOPUS, and Cochrane databases from inception to April 2018. The GRADE system was used to determine the quality of evidence for each measure evaluated in meta-analysis.Results: Respectively, seventeen and two studies having acceptable methodological quality were analyzed with regard to hamstring flexibility and stiffness. Four measures were identified for hamstring flexibility and five for stiffness. Meta-analyses were undertaken in straight leg raising (SLR), sit and reach and knee extension in 90° hip flexion for hamstring flexibility and for hamstring stiffness measures of stiffness at 50° SLR and gradient of stiffness from 20° to 50° SLR (M_e-grad). Significantly reduced hamstring flexibility or increased stiffness (P < .05) was detected in SLR, 90/90 knee extension and M_e-grad. However, the validity of measures for hamstring flexibility was problematic and GRADE scores for all measures in the meta-analyses were very low.Conclusion: There have been four measures for hamstring flexibility and five for stiffness to evaluate individuals with and without LBP. It was impossible to conclude whether individuals with LBP have impaired hamstring flexibility and stiffness due to very low quality of evidence for meta-analyses.

Non-Muscular Structures Can Limit the Maximal Joint Range of Motion during Stretching

Stretching is widely used in sport training and clinical practice with the aim of increasing muscle-tendon extensibility and joint range of motion. The underlying assumption is that extensibility increases as a result of increased passive tension applied to muscle-tendon units. In some stretching protocols, this condition is not always met sufficiently to trigger adaptation within the muscle-tendon unit. For example, there is experimental evidence that both acute and chronic stretching interventions may increase the maximal range of motion in the absence of changes in the passive torque-angle curve. We contend that these results are partly explained by the influence of non-muscular structures that contribute only marginally to the passive torque. The potential candidates are the nervous system and fasciae, which would play an important role in the perception of the stretch and in the limitation of the range of motion of the maximal joints. At least in part, this may explain the lack of a significant effect of some chronic stretching interventions to change passive muscle tension.

Femoral nerve excursion with knee and neck movements in supine, sitting and side-lying slump: An in vivo study using ultrasound imaging

BACKGROUND

Neurodynamic assessment and management are advocated for femoral nerve pathology. Contrary to neurodynamic techniques for other nerves, there is limited research that quantifies femoral nerve biomechanics.

OBJECTIVES

To quantify longitudinal and transverse excursion of the femoral nerve during knee and neck movements.

DESIGN

Single-group, experimental study, with within-participant comparisons.

METHODS

High-resolution ultrasound recordings of the femoral nerve were made in the proximal thigh/groin region in 30 asymptomatic participants. Scans were made during knee flexion in supine and a semi-seated position, and during neck flexion in side-lying slump (Slump _FEMORAL). Healthy participants were assessed to reveal normal nerve biomechanics, not influenced by pathology. Data were analysed with one-sample and paired t-tests. Reliability was assessed with intraclass correlation coefficients (ICC).

RESULTS

Longitudinal and transverse excursion measurements were reliable (ICC≥0.87). With knee flexion, longitudinal femoral nerve excursion was significant and larger in supine than in sitting (supine (mean (SD)): 3.6 (2.0) mm; p < 0.001; sitting: 1.1 (1.6) mm; p = 0.001; comparison: p = 0.001). There was also excursion in a medial direction (supine: 1.4 (0.3) mm; p < 0.001; sitting: 0.7 (0.6) mm; p < 0.001) and anterior direction (supine: 0.2 (0.2) mm; p < 0.001; sitting: 0.1 (0.2) mm; p = 0.06). Neck flexion in Slump _FEMORAL did not result in longitudinal (0.0 (0.3) mm; p = 0.55) or anteroposterior (0.0 (0.1) mm; p = 0.10) excursion, but resulted in medial excursion (1.1 (0.5) mm; p < 0.001).

CONCLUSION

Although the femoral nerve terminates proximal to the knee, femoral nerve excursion in the proximal thigh occurred with knee flexion; Neck flexion in Slump _FEMORAL resulted in medial excursion.

Clinical classification in low back pain: best-evidence diagnostic rules based on systematic reviews

Background

Clinical examination findings are used in primary care to give an initial diagnosis to patients with low back pain and related leg symptoms. The purpose of this study was to develop best evidence Clinical Diagnostic Rules (CDR] for the identification of the most common patho-anatomical disorders in the lumbar spine; i.e. intervertebral discs, sacroiliac joints, facet joints, bone, muscles, nerve roots, muscles, peripheral nerve tissue, and central nervous system sensitization.

Methods

A sensitive electronic search strategy using MEDLINE, EMBASE and CINAHL databases was combined with hand searching and citation tracking to identify eligible studies. Criteria for inclusion were: persons with low back pain with or without related leg symptoms, history or physical examination findings suitable for use in primary care, comparison with acceptable reference standards, and statistical reporting permitting calculation of diagnostic value. Quality assessments were made independently by two reviewers using the Quality Assessment of Diagnostic Accuracy Studies tool. Clinical examination findings that were investigated by at least two studies were included and results that met our predefined threshold of positive likelihood ratio ≥ 2 or negative likelihood ratio ≤ 0.5 were considered for the CDR.

Results

Sixty-four studies satisfied our eligible criteria. We were able to construct promising CDRs for symptomatic intervertebral disc, sacroiliac joint, spondylolisthesis, disc herniation with nerve root involvement, and spinal stenosis. Single clinical test appear not to be as useful as clusters of tests that are more closely in line with clinical decision making.

Conclusions

This is the first comprehensive systematic review of diagnostic accuracy studies that evaluate clinical examination findings for their ability to identify the most common patho-anatomical disorders in the lumbar spine. In some diagnostic categories we have sufficient evidence to recommend a CDR. In others, we have only preliminary evidence that needs testing in future studies. Most findings were tested in secondary or tertiary care. Thus, the accuracy of the findings in a primary care setting has yet to be confirmed.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-017-1549-6) contains supplementary material, which is available to authorized users.

Effects of lower body quadrant neural mobilization in healthy and low back pain populations: A systematic review and meta-analysis

BACKGROUND

Neural mobilization (NM) is widely used to assess and treat several neuromuscular disorders. However, information regarding the NM effects targeting the lower body quadrant is scarce.

OBJECTIVES

To determine the effects of NM techniques targeting the lower body quadrant in healthy and low back pain (LBP) populations.

DESIGN

Systematic review with meta-analysis.

METHOD

Randomized controlled trials were included if any form of NM was applied to the lower body quadrant. Pain, disability, and lower limb flexibility were the main outcomes. PEDro scale was used to assess methodological quality.

RESULTS

Forty-five studies were selected for full-text analysis, and ten were included in the meta-analysis, involving 502 participants. Overall, studies presented fair to good quality, with a mean PEDro score of 6.3 (from 4 to 8). Five studies used healthy participants, and five targeted people with LBP. A moderate effect size (g = 0.73, 95% CI: 0.48-0.98) was determined, favoring the use of NM to increase flexibility in healthy adults. Larger effect sizes were found for the effect of NM in pain reduction (g = 0.82, 95% CI 0.56-1.08) and disability improvement (g = 1.59, 95% CI: 1.14-2.03), in people with LBP.

CONCLUSION

Evidence suggests that there are positive effects from the application of NM to the lower body quadrant. Specifically, NM shows moderate effects on flexibility in healthy participants, and large effects on pain and disability in people with LBP. Nevertheless, more studies with high methodological quality are necessary to support these conclusions.

A Randomised, Placebo-Controlled Trial of Neurodynamic Sliders on Hamstring Responses in Footballers with Hamstring Tightness

BACKGROUND

Neurodynamics intervention is known to increase apparent muscle extensibility, but information regarding hamstring responses after a neurodynamic sliders (NS) technique is scarce. The aim of this study was to evaluate the effects of NS on apparent hamstring extensibility and activity in footballers with hamstring tightness.

METHODS

Forty eligible healthy male footballers with hamstring tightness were each randomly allocated to either a 4-week NS technique or a control group (CG) receiving placebo shortwave intervention. Knee extension angles were measured with the passive knee extension test, and maximal voluntary isometric contraction (MVIC) of hamstrings was measured by a surface electromyography at baseline and after intervention sessions.

RESULTS

The results showed that NS produced a statistically and clinically significant increase in knee extension angle compared to CG (P < 0.001); however, there was no difference between the groups receiving MVIC of hamstrings. Within group comparison, NS also provided a significant increase in knee extension angle (P < 0.001), whereas the control group did not. There was no change in hamstring MVIC in either group after intervention.

CONCLUSIONS

The findings of this study reveal that four weeks of NS technique improved apparent hamstring extensibility but did not change the hamstring activity in footballers with hamstring tightness.

Moving without moving: immediate management following lumbar spine surgery using a graded motor imagery approach: a case report

Representational body maps are dynamically maintained in the brain and negatively influenced by neglect, decreased movement and pain. Graded motor imagery (GMI) utilizing various tactile and cognitive processes has shown efficacy in decreasing pain, disability and movement restrictions in musculoskeletal pain. Limited information is known about the cortical changes patients undergo during lumbar surgery (LS), let alone the therapeutic effect of GMI for LS. A 56-year-old patient underwent LS for low back pain, leg pain and progressive neurological deficit. Twenty-four hours prior to and 48 h after LS various psychometric, physical movement and tactile acuity measurements were recorded. Apart from predictable postoperative increases in pain, fear-avoidance, disability and movement-restrictions, pressure pain thresholds (PPT), two-point discrimination (TPD) and tactile acuity was greatly reduced. The patient underwent six physiotherapy (PT) treatments receiving a GMI program aimed at restoring the PPT, TPD and tactile acuity. The results revealed that GMI techniques applied to a patient immediately after LS caused marked improvements in movement (flexion average improvement/session 3.3 cm; straight leg raise average 8.3°/session) and an immediate hypoalgesic effect. GMI may provide PT with a non-threatening therapeutic treatment for the acute LS patient and establish a new role for PT in acute LS patients.

The effects of neurodynamic straight leg raise treatment duration on range of hip flexion and protective muscle activity at P1

STUDY DESIGN

Randomized, single blind, same subject crossover trial.

OBJECTIVES

To compare the effects of two neurodynamic treatment doses on range of hip flexion (ROM HF) and electromyographic (EMG) activity of semitendinosus, at first onset of pain (P1).

METHODS

A total of 26 healthy participants without low back or leg pain received each treatment in a random order with at least 48 hours between sessions. Baseline ROM HF and EMG magnitude of semitendinosus at P1 were collected. Subjects then received either 361 or 362 minutes of oscillating end of range (grade IVz) straight leg raise (SLR) neurodynamic treatment and were re-assessed for baseline measures.

RESULTS

There was no significant difference between groups in EMG magnitude (P50.190) and ROM HF (P50.739) at P1. There was also no significant difference within groups in EMG magnitude at P1 (P50.182); however, there was a significant improvement in ROM HF at P1 in both groups compared to baseline readings (P50.000), with increases of 6.7u and 5.1u for the 361- and 362-minute groups, respectively.

CONCLUSION

Findings indicate that 362 minutes of oscillating grade IVz SLR neurodynamic treatment has no additional benefit over 361 minute, on ROM HF or EMG magnitude of semitendinosus at P1. Using an oscillating SLR treatment may, however, help to increase pain-free ROM HF, although further studies are necessary to confirm this.

Effects of lower limb neurodynamic mobilization on intraneural fluid dispersion of the fourth lumbar nerve root: an unembalmed cadaveric investigation

OBJECTIVES

Manual and physical therapists incorporate neurodynamic mobilisation (NDM) to improve function and decrease pain. Little is known about the mechanisms by which these interventions affect neural tissue. The objective of this research was to assess the effects of repetitive straight leg raise (SLR) NDM on the fluid dynamics within the fourth lumbar nerve root in unembalmed cadavers.

METHODS

A biomimetic solution (Toluidine Blue Stock 1% and Plasma) was injected intraneurally, deep to the epineurium, into the L4 nerve roots of seven unembalmed cadavers. The initial dye spread was allowed to stabilise and measured with a digital calliper. Once the initial longitudinal dye spread stabilised, an intervention strategy (repetitive SLR) was applied incorporating NDMs (stretch/relax cycles) at a rate of 30 repetitions per minute for 5 minutes. Post-intervention calliper measurements of the longitudinal dye spread were measured.

RESULTS

The mean experimental posttest longitudinal dye spread measurement (1.1 ± 0.9 mm) was significantly greater (P = 0.02) than the initial stabilised pretest longitudinal dye spread measurement. Increases ranged from 0.0 to 2.6 mm and represented an average of 7.9% and up to an 18.1% increase in longitudinal dye spread.

DISCUSSION

Passive NDM in the form of repetitive SLR induced a significant increase in longitudinal fluid dispersion in the L4 nerve root of human cadaveric specimen. Lower limb NDM may be beneficial in promoting nerve function by limiting or altering intraneural fluid accumulation within the nerve root, thus preventing the adverse effects of intraneural oedema.

Comparison of location, depth, quality, and intensity of experimentally induced pain in 6 low back muscles

INTRODUCTION

The pattern of pain originating from experimentally induced low back pain appears diffuse. This may be because sensory information from low back muscles converges, sensory innervation extends over multiple vertebral levels, or people have difficulty accurately representing the painful location on standardized pain maps.

OBJECTIVE

The aim of this study was to provide insight into the perception of pain from noxious stimulation of a range of low back muscles using novel depth and location measures.

METHODS

Hypertonic saline (1 mL, 7% NaCl) was injected into bellies of longissimus (LO), quadratus lumborum (QL), superficial multifidus (SM), and deep multifidus (DM) at the level of the fourth lumbar vertebrae (L4) and in SM and DM at L5 using ultrasound guidance over 6 sessions. Fifteen participants reported depth, location, intensity, size, and descriptive quality of pain throughout the painful period (∼14 min).

RESULTS

Pain was reported deeper (P<0.04) for DML4/L5 compared with SML4/L5, LO and QL; more cranial for LO compared with DML4 and QL (P<0.01); more lateral for LO compared with DML4 (P<0.02); and more lateral for QL compared with all other muscles at L4 (P<0.0001). Pain intensity was higher in DML4/L5 than all other muscles (P<0.04) for ∼3 minutes. Descriptive qualities varied slightly between muscles.

DISCUSSION

Depth and lateral position may be the most critical descriptors to determine the source of acute lumbar muscular pain. Overlapping regions of pain may be explained by convergence of receptive fields, innervation of multifidus fascicles at multiple lumbar segments, and convergence of sensory input from different muscles to the same sensory cell bodies as demonstrated in the lumbar spine of animal preparations.

Neurodynamic responses to the femoral slump test in patients with anterior knee pain syndrome

STUDY DESIGN

Matched-control, cross-sectional study.

OBJECTIVES

The purpose of this study was to compare the responses to the femoral slump test (FST), including the change in hip range of motion and level of discomfort, between subjects with and without anterior knee pain.

BACKGROUND

Anterior knee pain syndrome is a common problem among adults. The FST is the neurodynamic test used to assess the mechanosensitivity of the femoral component of the nervous system. However, as of yet, there is no literature discussing the use of the FST in patients with anterior knee pain.

METHODS

Thirty patients with anterior knee pain and 30 control participants, matched by gender, age, and dominant leg, were recruited. The subjects received the FST, during which the hip extension angle and the location and intensity of pain/discomfort were recorded. Reproduction of symptoms that were alleviated by neck extension was interpreted as a positive test. Differences in hip extension angle and pain intensity between groups were examined using a 2-way, repeated-measures analysis of variance and a Kruskal-Wallis analysis. The level of significance was set at α = .05.

RESULTS

Subjects with anterior knee pain had a smaller hip extension angle than that of controls (-3.6° ± 5.3° versus 0.6° ± 6.1°; mean difference, 4.2°; 95% confidence interval [CI]: 1.24°, 7.15°; P = .006). Eight patients with anterior knee pain showed a positive FST, and those with a positive FST had a smaller hip extension angle (-5.7° ± 4.5°) than that of controls (mean difference, 6.3°; 95% CI: 0.8°, 11.8°; P = .007). There was no difference in the hip extension angle between the positive and negative FST groups (mean difference, 2.9°; 95% CI: -8.5°, 2.0°) or between the negative FST and control groups (mean difference, 3.4°; 95% CI: -0.4°, 7.3°).

CONCLUSION

Results of this study suggest that altered mechanosensitivity of the femoral nerve occurred in the patients with anterior knee pain who presented with a positive FST. The role of increased mechanosensitivity in the development and management of anterior knee pain should be investigated in the future.

Normal inter-limb differences during the straight leg raise neurodynamic test: a cross sectional study

Background

The straight leg raise (SLR) neurodynamic test is commonly used to examine the sensitivity of the lower quarter nervous system to movement. Range of motion during the SLR varies considerably, due to factors such as age, sex and activity level. Knowing intra-individual, inter-limb differences may provide a normative measure that is not influenced by such demographic characteristics. This study aimed to determine normal asymmetries between limbs in healthy, asymptomatic individuals during SLR testing and the relationship of various demographic characteristics.

Methods

The limb elevation angle was measured using an inclinometer during SLR neurodynamic testing that involved pre-positioning the ankle in plantar flexion (PF/SLR) and neutral dorsiflexion (DF/SLR). Phase 1 of the study included 20 participants where the ankle was positioned using an ankle brace replicating research testing conditions. Phase 2 included 20 additional participants where the ankle was manually positioned to replicate clinical testing conditions.

Results

The group average range of motion during PF/SLR was 57.1 degrees (SD: 16.8 degrees) on the left and 56.7 degrees (SD: 17.2 degrees) on the right while during DF/SLR the group average was 48.5 degrees (SD: 16.1 degrees) on the left and 48.9 degrees (SD: 16.4 degrees) on the right. The range of motion during SLR was moderately correlated to weight (−0.40 to −0.52), body mass index (−0.41 to −0.52), sex (0.40 to 0.42) and self-reported activity level (0.50 to 0.57). Intra-individual differences between limbs for range of motion during PF/SLR averaged 5.0 degrees (SD: 3.5 degrees) (95% CI: 3.8 degrees, 6.1 degrees) and during DF/SLR averaged 4.1 degrees (SD: 3.2 degrees) (95% CI: 3.1 degrees, 5.1 degrees) but were not correlated with any demographic characteristic. There were no significant differences between Phase 1 and Phase 2.

Conclusions

Overall range of motion during SLR was related to sex, weight, BMI and activity level, which is likely reflected in the high variability documented. We can be 95% confident that inter-limb differences during SLR neurodynamic testing fall below 11 degrees in 90% of the general population of healthy individuals. In addition, inter-limb differences were not affected by demographic factors and thus may be a more valuable comparison for test interpretation.

The effects of neurodynamic mobilization on fluid dispersion within the tibial nerve at the ankle: an unembalmed cadaveric study

OBJECTIVE

To evaluate the effects of neurodynamic mobilization on the fluid dynamics of the tibial nerve in cadavers.

BACKGROUND

Evidence showing patients benefit from neural mobilization is limited. Mechanisms responsible for changes in patient symptoms are unclear.

METHODS

Bilateral lower limbs of six unembalmed cadavers (n = 12) were randomized into matched pairs and dissected to expose the tibial nerve proximal to the ankle. Dye composed of Toulidine blue and plasma was injected into the nerve. The longitudinal dye spread was measured pre- and post-mobilization. The experimental group received the intervention consisting of 30 repetitions of passive ankle range of motion over the course of 1 minute. The matched control limb received no mobilization. Data were analysed using a 2×2 repeated measures ANOVA with subsequent t-tests for pairwise comparisons.

RESULTS

Mean dye spread was 23.8±10.2 mm, a change of 5.4±4.7% in the experimental limb as compared to 20.7±6.0 mm, a change of -1.5±3.9% in the control limb. The ANOVA was significant (P⩽0.02) for interaction between group (experimental/control) and time (pre-mobilization/post-mobilization). t-test results were significant between pre- and post-mobilization of the experimental leg (P = 0.01), and between control and experimental limbs post-mobilization (P⩽0.02).

CONCLUSION

Passive neural mobilization induces dispersion of intraneural fluid. This may be clinically significant in the presence of intraneural edema found in pathological nerves such as those found in compression syndromes.

Interventions in the disturbances in the motor and sensory environment

Treatment of peripheral nervous system (PNS) pathology presents intervention challenges to every therapist. Many of the current and future interventions will be directed at restoring the normal anatomy, function, and biomechanical properties of the PNS, restoring normal neural physiology and ultimately patient function and quality of life. Present interventions use mechanical (movement) or electrical procedures to affect various properties of the peripheral nerve. The purpose of this article was to apply basic science to clinical practice. The pathology and accompanying structural and biomechanical changes in the PNS will be presented in three specific areas commonly encountered in the clinic: nerve injury and laceration; compression neuropathies; and neuropathic pain and neural tension dysfunction. The intent is to address possible interventions exploring the clinical reasoning process that combines basic science and evidence-based best practice. The current lack of literature to support any one intervention requires a strong foundation and understanding of the PNSs' structure and function to refine current and develop new intervention strategies. Current evidence will be presented and linked with future considerations for intervention and research. During this interlude of development and refinement, best practice will rely on sound clinical reasoning skills that incorporate basic science to achieve a successful outcome when treating these challenging patients.

Slump test: sensory responses in asymptomatic subjects

The Slump Test is used as a fast, low-cost diagnostic tool in the evaluation of leg and back pain disorders. The purpose of this study was to identify the normative sensory responses to the Slump Test in asymptomatic subjects. Eighty-four subjects were tested using a standardized procedure by the same examiner to ensure consistency. Prevalence, intensity, location, and nature of responses at each stage of the Slump Test [Slumped Sitting (SS), Knee Extension (KE), Ankle Dorsiflexion (AD), and Cervical Extension (CE)] were recorded. Of the subjects, 97.6% reported a sensory response during the Slump Test. Prevalence of responses increased significantly from 29.8% at SS to 94% at KE and decreased significantly from 97.6% at AD to 65.5% at CE. Median intensity of responses increased significantly from 0/10 at SS, through 4/10 at KE, to 6/10 at AD, and then decreased significantly to 2/10 at CE. At SS, responses were located at the back or neck, but during the subsequent stages, responses were located most commonly in the posterior thigh, knee, and calf. In terms of nature, a number of different descriptors were used, the most common being "stretch," "tight," and "pull." Approximately 80% of subjects reporting a response had complete or partial relief of this response following cervical extension, indicating that the normal response to the Slump Test may be considered a neurogenic response. This normative data may be used as a reference point when using the Slump Test in the examination of leg and back pain disorders.

Practical use of the HOAC II for clinical decision making and subsequent therapeutic interventions in an elite athlete with low back pain

STUDY DESIGN

Resident's case problem.

BACKGROUND

This case report describes the diagnostic process, based on the Hypothesis-Oriented Algorithm for Clinicians II (HOAC II), and subsequent interventions in an elite athlete with subacute low back pain. It also demonstrates the clinical application of the HOAC II and shows how disablement terms, as used in the World Health Organization's International Classification of Functioning, Disability and Health model, can be integrated into patient management in a manner that we believe enhances clinical practice. It also demonstrates the practical use of validated questionnaires and how these can be used to gather necessary information for the algorithm.

DIAGNOSIS

A structured, evidence-based assessment led to a multifaceted, activity limitation-based diagnosis of being unable to (1) remain in a deep squat position during speed skating, (2) accelerate in turns while speed skating, and (3) rise from a slouched position without pain. We believed that these dysfunctions were due to local limited lumbar segmental mobility, concurrent with an inability to properly and functionally stabilize the lumbopelvic area.

DISCUSSION

The HOAC II requires the therapist to develop an evidence-based strategy for the examination that is based on initial hypotheses developed from the medical history and other data obtained prior to the examination. The examination was tailored to identify and quantify activity limitations and participation restrictions that we believed could help to explain why this patient had his health problem. The case demonstrates how all elements of the HOAC II can be used for what we consider to be relatively common types of patients. We believe that by applying the HOAC II on an individual-patient basis, therapists will be ideally positioned to apply evidence to patient care and to defend their interventions to colleagues and third-party payers.

LEVEL OF EVIDENCE

Differential diagnosis, level 4.

Mechanosensitivity during lower extremity neurodynamic testing is diminished in individuals with Type 2 Diabetes Mellitus and peripheral neuropathy: a cross sectional study

Background

Type 2 Diabetes Mellitus (T2DM) and diabetic symmetrical polyneuropathy (DSP) impact multiple modalities of sensation including light touch, temperature, position sense and vibration perception. No study to date has examined the mechanosensitivity of peripheral nerves during limb movement in this population. The objective was to determine the unique effects T2DM and DSP have on nerve mechanosensitivity in the lower extremity.

Methods

This cross-sectional study included 43 people with T2DM. Straight leg raise neurodynamic tests were performed with ankle plantar flexion (PF/SLR) and dorsiflexion (DF/SLR). Hip flexion range of motion (ROM), lower extremity muscle activity and symptom profile, intensity and location were measured at rest, first onset of symptoms (P1) and maximally tolerated symptoms (P2).

Results

The addition of ankle dorsiflexion during SLR testing reduced the hip flexion ROM by 4.3° ± 6.5° at P1 and by 5.4° ± 4.9° at P2. Individuals in the T2DM group with signs of severe DSP (n = 9) had no difference in hip flexion ROM between PF/SLR and DF/SLR at P1 (1.4° ± 4.2°; paired t-test p = 0.34) or P2 (0.9° ± 2.5°; paired t-test p = 0.31). Movement induced muscle activity was absent during SLR with the exception of the tibialis anterior during DF/SLR testing. Increases in symptom intensity during SLR testing were similar for both PF/SLR and DF/SLR. The addition of ankle dorsiflexion induced more frequent posterior leg symptoms when taken to P2.

Conclusions

Consistent with previous recommendations in the literature, P1 is an appropriate test end point for SLR neurodynamic testing in people with T2DM. However, our findings suggest that people with T2DM and severe DSP have limited responses to SLR neurodynamic testing, and thus may be at risk for harm from nerve overstretch and the information gathered will be of limited clinical value.

Hydroxyproline Levels in Young Adults Undergoing Muscular Stretching and Neural Mobilization

This study aimed to assess the acute effect of stretching and neural mobilization on urinary hydroxyproline (HP) levels in young adults. The sample, composed of physical therapy students from Teresina (PI), was divided into three groups: a neural mobilization group (NMG; n=15; age=22±3 years; BMI=24.75±3.09); a static stretching group (SSG; n=15; age=23±4 years; BMI: 25±4.33) and a control group (CG; n=15; age: 24±4 years; BMI: 23.91±3.09). The NMG underwent neural mobilization of the sciatic nerve while engaged in hip flexion with knee extension in a direct, oscillatory and strenuous manner for 60 seconds. The SSG performed passive static stretching, which consisted of the maintenance of a high amplitude posture, without exceeding the limits of the movement, for a period of tension ranging from four to six seconds. Urinary HP was evaluated at the baseline and 24 hours after the intervention using the colorimetric method. Repeated measures ANOVA showed significant intragroup increases in the NMG (Δ7.38 mg/24h; p=0.0001) and the SSG (Δ=3.47 mg/24h; p=0.002) and inter-group increases in the NMG (Δ%=118.89%) when compared to the SSG (Δ%=60.32%; p=0.006) and the CG (Δ%=-0.91%; p=0.0001). These results indicate that the NMG worked with tension beyond the ordinary amplitude arches of articular movement, thus causing a restructuring of collagen.

Upper limb neurodynamic test of the radial nerve: a study of responses in symptomatic and asymptomatic subjects

STUDY DESIGN

Clinical measurement.

INTRODUCTION

Nonspecific cervical pain is a common clinical presentation. The role of upper limb neurodynamic tests (ULNT), for evaluation and treatment intervention, is not well defined for this population.

PURPOSE OF THE STUDY

This study's purpose was to determine if the radial-biased (RB)-ULNT discriminates any response differences between symptomatic subjects with a positive (+) RB-ULNT (n=36), symptomatic subjects with a negative (-) RB-ULNT (n=24), and asymptomatic subjects (n=60).

METHODS

Sixty asymptomatic and 60 subjects presenting with nonspecific cervical and/or unilateral upper extremity pain were compared using the RB-ULNT. Symptomatic subjects were further divided in (+) and (-) RB-ULNT groups due to their response to the RB-ULNT. Within the symptomatic population, a positive response to the RB-ULNT was defined by the symptomatic subject reporting their sensations were increased with contralateral cervical lateral flexion and decreased with ipsilateral cervical lateral flexion. Sensation provocation and location were evaluated using the RB-ULNT in all the subjects during each stage of the testing.

RESULTS

Significant differences on stage of reproduction and type of sensations were identified between 1) the (+) RB-ULNT symptomatic subjects, 2) the (-) RB-ULNT symptomatic subjects, and 3) the asymptomatic subjects. The (+) RB-ULNT group showed significantly increased pain responses during the first stage of the RB-ULNT compared with the (-) RB-ULNT group and the asymptomatic subjects. The (+) RB-ULNT also showed significantly decreased glenohumeral abduction passive range of motion when compared with the asymptomatic group.

CONCLUSION

Clinically, the differences found between the groups in their response to the RB-ULNT suggest heightened mechanosensitivity in the (+) RB-ULNT group.

LEVEL OF EVIDENCE

3a.

Mechanosensitivity of the lower extremity nervous system during straight-leg raise neurodynamic testing in healthy individuals

STUDY DESIGN

Cross-sectional, observational study.

OBJECTIVES

To explore how ankle position affects lower extremity neurodynamic testing.

BACKGROUND

Upper extremity limb movements that increase neural loading create a protective muscle action of the upper trapezius, resulting in shoulder girdle elevation during neurodynamic testing. A similar mechanism has been suggested in the lower extremities.

METHODS

Twenty healthy subjects without low back pain participated in this study. Hip flexion angle and surface electromyographic measures were taken and compared at the onset of symptoms (P1) and at the point of maximally tolerated symptoms (P2) during straight-leg raise tests performed with ankle dorsiflexion (DF-SLR) and plantar flexion (PF-SLR).

RESULTS

Hip flexion was reduced during DF-SLR by a mean +/- SD of 5.5 degrees +/- 6.6 degrees at P1 (P = .001) and 10.1 degrees +/- 9.7 degrees at P2 (P<.001), compared to PF-SLR. DF-SLR induced distal muscle activation and broader proximal muscle contractions at P1 compared to PF-SLR.

CONCLUSION

These findings support the hypothesis that addition of ankle dorsiflexion during straight-leg raise testing induces earlier distal muscle activation and reduces hip flexion motion. The straight-leg test, performed to the onset of symptoms (P1) and with sensitizing maneuvers, allows for identification of meaningful differences in test outcomes and is an appropriate end point for lower extremity neurodynamic testing.

Pain patterns and descriptions in patients with radicular pain: does the pain necessarily follow a specific dermatome?

Background

It is commonly stated that nerve root pain should be expected to follow a specific dermatome and that this information is useful to make the diagnosis of radiculopathy. There is little evidence in the literature that confirms or denies this statement. The purpose of this study is to describe and discuss the diagnostic utility of the distribution of pain in patients with cervical and lumbar radicular pain.

Methods

Pain drawings and descriptions were assessed in consecutive patients diagnosed with cervical or lumbar nerve root pain. These findings were compared with accepted dermatome maps to determine whether they tended to follow along the involved nerve root's dermatome.

Results

Two hundred twenty-six nerve roots in 169 patients were assessed. Overall, pain related to cervical nerve roots was non-dermatomal in over two-thirds (69.7%) of cases. In the lumbar spine, the pain was non-dermatomal in just under two-thirds (64.1%) of cases. The majority of nerve root levels involved non-dermatomal pain patterns except C4 (60.0% dermatomal) and S1 (64.9% dermatomal). The sensitivity (SE) and specificity (SP) for dermatomal pattern of pain are low for all nerve root levels with the exception of the C4 level (Se 0.60, Sp 0.72) and S1 level (Se 0.65, Sp 0.80), although in the case of the C4 level, the number of subjects was small (n = 5).

Conclusion

In most cases nerve root pain should not be expected to follow along a specific dermatome, and a dermatomal distribution of pain is not a useful historical factor in the diagnosis of radicular pain. The possible exception to this is the S1 nerve root, in which the pain does commonly follow the S1 dermatome.

Agreement and correlation between the straight leg raise and slump tests in subjects with leg pain

OBJECTIVE

The straight leg raise (SLR) and slump tests have traditionally been used to identify nerve root compression arising from disk herniation. However, they may be more appropriate as tests of lumbosacral neural tissue mechanosensitivity. The aim of this study was to determine agreement and correlation between the SLR and slump tests in a population presenting with back and leg pain.

METHODS

This was an observational, cross-sectional study design. Forty-five subjects with unilateral leg pain were recruited from an outpatient Back Pain Screening Clinic at a large teaching hospital in Ireland. The SLR and slump tests were performed on each side. In the event of symptom reproduction, the ankle was dorsiflexed. Reproduction of presenting symptoms, which were intensified by ankle dorsiflexion, was interpreted as a positive test. An inclinometer was used to measure range of motion (ROM).

RESULTS

There was substantial agreement between SLR and slump test interpretation (kappa = 0.69) with good correlation in ROM between the 2 tests (r = 0.64) on the symptomatic side. In subjects who had positive results, ROM for both tests was significantly reduced compared to ROM on the contralateral side and ROM in subjects who had negative results.

CONCLUSIONS

When the SLR and slump tests are interpreted as positive in the event of reproduction of presenting leg pain that are intensified by ankle dorsiflexion, these tests show substantial agreement and good correlation in the leg pain population. When interpreted in this way, these tests may be appropriate tests of neural tissue mechanosensitivity, but further criteria must be met before a definitive conclusion in relation to neural tissue mechanosensitivity may be drawn.

Reliability of clinical tests to evaluate nerve function and mechanosensitivity of the upper limb peripheral nervous system

Background

Clinical tests to assess peripheral nerve disorders can be classified into two categories: tests for afferent/efferent nerve function such as nerve conduction (bedside neurological examination) and tests for increased mechanosensitivity (e.g. upper limb neurodynamic tests (ULNTs) and nerve palpation). Reliability reports of nerve palpation and the interpretation of neurodynamic tests are scarce. This study therefore investigated the intertester reliability of nerve palpation and ULNTs. ULNTs were interpreted based on symptom reproduction and structural differentiation. To put the reliability of these tests in perspective, a comparison with the reliability of clinical tests for nerve function was made.

Methods

Two experienced clinicians examined 31 patients with unilateral arm and/or neck pain. The examination included clinical tests for nerve function (sensory testing, reflexes and manual muscle testing (MMT)) and mechanosensitivity (ULNTs and palpation of the median, radial and ulnar nerve). Kappa statistics were calculated to evaluate intertester reliability. A meta-analysis determined an overall kappa for the domains with multiple kappa values (MMT, ULNT, palpation). We then compared the difference in reliability between the tests of mechanosensitivity and nerve function using a one-sample t-test.

Results

We observed moderate to substantial reliability for the tests for afferent/efferent nerve function (sensory testing: kappa = 0.53; MMT: kappa = 0.68; no kappa was calculated for reflexes due to a lack of variation). Tests to investigate mechanosensitivity demonstrated moderate reliability (ULNT: kappa = 0.45; palpation: kappa = 0.59). When compared statistically, there was no difference in reliability for tests for nerve function and mechanosensitivity (p = 0.06).

Conclusion

This study demonstrates that clinical tests which evaluate increased nerve mechanosensitivity and afferent/efferent nerve function have comparable moderate to substantial reliability. To further investigate the clinometric properties of these tests, more studies are needed to evaluate their validity.

Reliability and measurement error of active knee extension range of motion in a modified slump test position: a pilot study

The slump test is a tool to assess the mechanosensitivity of the neuromeningeal structures within the vertebral canal. While some studies have investigated the reliability of aspects of this test within the same day, few have assessed the reliability across days. Therefore, the purpose of this pilot study was to investigate reliability when measuring active knee extension range of motion (AROM) in a modified slump test position within trials on a single day and across days. Ten male and ten female asymptomatic subjects, ages 20-49 (mean age 30.1, SD 6.4) participated in the study. Knee extension AROM in a modified slump position with the cervical spine in a flexed position and then in an extended position was measured via three trials on two separate days. Across three trials, knee extension AROM increased significantly with a mean magnitude of 2 degrees within days for both cervical spine positions (P>0.05). The findings showed that there was no statistically significant difference in knee extension AROM measurements across days (P>0.05). The intraclass correlation coefficients for the mean of the three trials across days were 0.96 (lower limit 95% CI: 0.90) with the cervical spine flexed and 0.93 (lower limit 95% CI: 0.83) with cervical extension. Measurement error was calculated by way of the typical error and 95% limits of agreement, and visually represented in Bland and Altman plots. The typical error for the cervical flexed and extended positions averaged across trials was 2.6 degrees and 3.3 degrees , respectively. The limits of agreement were narrow, and the Bland and Altman plots also showed minimal bias in the joint angles across days with a random distribution of errors across the range of measured angles. This study demonstrated that knee extension AROM could be reliably measured across days in subjects without pathology and that the measurement error was acceptable. Implications of variability over multiple trials are discussed. The modified set-up for the test using the Kincom dynamometer and elevated thigh position may be useful to clinical researchers in determining the mechanosensitivity of the nervous system.

2006 Young Investigator Award Winner: lumbosacral nerve root displacement and strain: part 2. A comparison of 2 straight leg raise conditions in unembalmed cadavers

STUDY DESIGN

An inferential cadaveric study.

OBJECTIVES

To compare the displacement and strain of the lumbosacral nerve roots during different conditions of straight leg raise (SLR) with intact foraminal ligaments.

SUMMARY OF BACKGROUND DATA

Clinicians use sensitizing movements such as dorsiflexion during neurodynamic testing, assuming that these prepositions influence the displacement or strain to the lumbosacral nerve roots. Little is known about the effect of these prepositions on neurodynamic behavior.

METHODS

Lower limbs and associated nerve roots of 5 unembalmed cadavers (n = 10) were used to evaluate the displacement and strain of the L4, L5, and S1 roots during 2 different SLR conditions. Fluoroscopic images of intraneural metal markers were digitized to evaluate displacement and strain during SLR with no preposition (SLR NPP) of the ankle and SLR with dorsiflexion preposition (SLR DF) of the ankle, respectively.

RESULTS

SLR NPP produced larger distal displacement at L5 and S1, (P < 0.001) when compared with SLR DF. Displacement comparisons at L4 were nonsignificant (P = 0.051). While nonsignificant, medium to large effect sizes (0.60-0.96) suggest that SLR DF may produce more strain than the SLR NPP condition.

CONCLUSIONS

Prepositions of the SLR test alter the displacement and possibly the strain of the lumbosacral nerve roots in the lateral recess.

What is the normal response to structural differentiation within the slump and straight leg raise tests?

The purpose of the study was to assess the effect of structural differentiation or sensitising manoeuvres on responses of normal subjects to standard neurodynamic tests of straight leg raise (SLR) and slump test. Eighty-eight (39 males and 49 females) asymptomatic subjects were examined (aged 18-39 mean age 21.9+/-4.1 years). Knee flexion angle was measured using a goniometer during the slump test in two conditions cervical flexion and extension. Hip flexion angle was measured using a goniometer during SLR test in two conditions; ankle dorsi-flexion and neutral. The change in knee flexion, following addition of the structural differentiating manoeuvre to the slump test, was a significant increase in knee flexion angle for both males (change in knee angle; 6.6+/-4.7 degrees /18.7+/-17.5%, p<0.01) and females (change in knee angle 5.4+/-5.8 degrees /17.6+/-23.7%, p<0.01), though showed no difference between sides (p>0.05). During the SLR test, a significant reduction in hip flexion occurred following structural differentiation for both groups (change in hip angle; males = 9.5+/-8.3 degrees /21.5+/-18.8%, p<0.01; females = 15.2+/-9.5 degrees /25.9+/-13.9%, p<0.01), though showed no difference between sides (p>0.05). Structural differentiating manoeuvres have a significant effect on test response in terms of range of movement even in normal asymptomatic individuals. These responses should be taken into account during the assessment clinical reasoning process.