The Concept of Adverse Mechanical Tension in the Nervous System Part 1: Testing for “Dural tension”

Altered Cervical Spine Position Results in Decreased Eccentric Shoulder Rotation Strength

Overhead athletes require strenuous shoulder activity in nonneutral cervical spine positions to eccentrically decelerate the throwing/striking arm following ball release/contact. We therefore aimed to compare eccentric shoulder rotation strength through a 90° arc between neutral and rotated positions. Fifty-two participants (19 M, 34 F 170±10 cm; 73±18 kg, 21.9±2.9 years) without shoulder or cervical spine pathology participated. Isokinetic eccentric shoulder rotation strength was measured through a 90° arc with the shoulder elevated 90° in frontal plane (frontal plane), and 45° anterior to the frontal plane (scapular plane) in neutral and rotated cervical spine positions. Cervical spine position was obtained by instructing participants to maximally rotate their respective side. Frontal plane eccentric external rotated strength differed between neutral and contralaterally positions in the first 10° of the motion, near forearm vertical (p+=+0.029). Internal rotation strength differed between neutral and contralaterally rotated positions from 55-60° external rotation (p+=+0.004). Scapular plane eccentric external rotation differed between cervical positions between 21-67° shoulder external rotation (p<0.001). Scapular plane internal rotation strength differed between cervical positions between 22-60° shoulder external rotation (p<0.001). In populations requiring strenuous use of their shoulders in altered cervical spine positions, sports medicine clinicians should consider including strength testing that reflects the functional positions of their patients during an orthopedic examination.

Impact of the Order of Movement on the Median Nerve Root Function: A Neurophysiological Study with Implications for Neurodynamic Exercise Sequencing

Background: Neurodynamic exercise is a common clinical practice used to restore neural dynamic balance. The order in which movements are performed during these exercises is believed to play a crucial role in their effectiveness. This study aimed to investigate the impact of different sequences of neurodynamic exercise on nerve root function, with a specific focus on the median nerve. Methods: Participants were assigned randomly to three experimental groups, each undergoing a different test sequence: standard, proximal-to-distal, and distal-to-proximal. Dermatomal somatosensory evoked potentials (DSSEPs) were recorded at key levels (C6, C7, C8, and T1). Results: The findings revealed a significant influence of the movement sequence on DSSEP amplitudes. The execution of neurodynamic exercise in the proximal-to-distal sequence was associated with a notable reduction in amplitudes (p < 0.05). Conversely, the distal-to-proximal sequence resulted in increased amplitudes compared to the standard sequence (p < 0.05). Conclusions: This study underscores the importance of carefully considering the order of movements during neurodynamic exercising, particularly when evaluating nerve roots that lack the protective perineurium. The choice of sequence appears to have a substantial impact on nerve function, with implications for optimizing clinical neurodynamic exercise techniques.

Mechanical Effects of a Specific Neurodynamic Mobilization of the Superficial Fibular Nerve: A Cadaveric Study

CONTEXT

A specific neurodynamic mobilization for the superficial fibular nerve (SFN) has been suggested in the reference literature for manual therapists to evaluate nerve mechanosensitivity in patients. However, no authors of biomechanical studies have examined the ability of this technique to produce nerve strain. Therefore, the mechanical specificity of this technique is not yet established.

OBJECTIVES

To test whether this examination and treatment technique produced nerve strain in the fresh frozen cadaver and the contribution of each motion to total longitudinal strain.

DESIGN

Controlled laboratory study.

SETTING

Laboratory.

MAIN OUTCOME MEASURE(S)

A differential variable reluctance transducer was inserted in 10 SFNs from 6 fresh cadavers to measure strain during the mobilization. A specific sequence of plantar flexion, ankle inversion, straight-leg raise position, and 30° of hip adduction was applied to the lower limb. The mobilization was repeated at 0°, 30°, 60°, and 90° of the straight-leg raise position to measure the effect of hip-flexion position.

RESULTS

Compared with a resting position, this neurodynamic mobilization produced a significant amount of strain in the SFN (7.93% ± 0.51%, P < .001). Plantar flexion (59.34% ± 25.82%) and ankle inversion (32.80% ± 21.41%) accounted for the biggest proportions of total strain during the mobilization. No difference was noted among different hip-flexion positions. Hip adduction did not significantly contribute to final strain (0.39% ± 10.42%, P > .05), although high variability among limbs existed.

CONCLUSIONS

Ankle motion should be considered the most important factor during neurodynamic assessment of the SFN for distal entrapment. These results suggest that this technique produces sufficient strain in the SFN and could therefore be evaluated in vivo for correlation with mechanosensitivity.

Comparative Effects of Tensioning and Sliding Neural Mobilization on Peripheral and Autonomic Nervous System Function: A Randomized Controlled Trial

Background:

Although different types of neural mobilization (NM) exercises induce different amounts of longitudinal nerve excursion and strain, the question whether the increased longitudinal stress and nerve excursion from sliding or tensioning intervention may subtly affect the neural functions has not been answered yet.

Objective:

To compare the effects of tensioning NM versus sliding NM of the median nerve on peripheral and autonomic nervous system function.

Methods:

In this randomized controlled trial, 90 participants were randomly assigned to tensioning NM, sliding NM, or sham NM. The neurophysiological outcome measures included peak-to-peak amplitude of the dermatomal somatosensory evoked potential (DSSEP) for dermatomes C6, C7, C8, and T1. Secondary outcome measures included amplitude and latency of skin sympathetic response. All outcome measures were assessed pretreatment, immediately after the two weeks of treatment and one week after the last session of the treatment.

Results:

A 2-way repeated measures ANOVA revealed significant differences between the three groups. The post hoc analysis indicated that tensioning NM significantly decreased the dermatomal amplitude for C6, C7, C8, and T1 (p<0.005). Sympathetic skin responses in the gliding NM group showed lower amplitudes and prolonged latencies post-treatment when compared to tensioning NM group (p<0.05). In contrast, no significant changes were observed in the DSSEPs and skin sympathetic responses for participants in the sham treatment group (p>0.05).

Conclusions:

A tensioning NM on the median nerve had a possible adverse effect on the neurophysiology variables of the nerves involved in the neural mobilization. Thus, tensioning NM with the current parameters that place increased stress and strain on the peripheral nervous system should be avoided.

Update on the thoracic outlet syndrome and plexus brachial syndrome: Specific clinical examination (for all) and rehabilitation protocol

The diagnosis of uncomplicated forms of thoracobrachial outlet syndrome (TOS) and brachial plexus stretching syndrome (BPSS) is imprecise due to the lack of clear differentiation between dynamic vascular or neurological compression and brachial plexus stretching without vascular compression. After a review of literature, we propose and describe a simple way for clinical assessment of TOS, BPSS or association of both comprising 1 clinical sign and 2 manoeuvres. This clinical assessment can be performed by the medical doctor, the physiotherapist and the surgeon. The clinical diagnosis is essential because it will dictate the rehabilitation treatment. We propose and describe also a rehabilitation protocol comprising 10 phases with modulation of exercises according to clinical form (TOS, BPSS or association) and/or severity of symptoms. The physiotherapist has a capital role and is the guarantor of the effectiveness of the medical treatment. In France, a training is now available thanks to personal continuous development for diagnosis and treatment of TOS and BPSS. This is essential in order to propose an optimal care to patients.

The effectiveness of routine physiotherapy with and without neuromobilization on pain and functional disability in patients with shoulder impingement syndrome; a randomized control clinical trial

Background

The objective of the study was to compare the effects of neuromobilization (NM) techniques and routine physiotherapy on pain and functional disability in patients having shoulder impingement syndrome (SIS). Present study was aimed to discover evidence based conservative and cost effective remedy on pain and functional disability.

Study design

Single blinded randomized control clinical trial.

Methods

A total of 80 patients with SIS were randomly assigned into care and experimental groups (40 in each group). After the baseline assessment routine physiotherapy was executed on both groups, while NM was applied additionally to experimental group. Pain and functional disability score were evaluated by Visual Analogue Scale and University of California at Los Angeles rating score at baseline, 5th and 11th week. Differences in outcome between groups were evaluated with clinical improvement.

Results

The experimental group compared with care group at 11th week had lower mean pain score 2.15(1.66–2.64) vs 4.90(4.41–5.40); between group difference, 1.82; 95% (CI), − 2.38 to − 1.25; P < 0.001 and Partial ƞ² = 0.33, similarly functional disability score 28.58(27.32–29.83) vs 20.10(18.84–21.36); between group difference,5.62; 95%CI, (4.32–6.92); P< 0.001 and Partial ƞ² = 0.49 respectively. In experimental group NM was a more effective technique to reduce the pain severity and disability in SIS patients as compare to care group.

Conclusion

Neuromobilization techniques in addition to routine physiotherapy were significantly effective for the treatment of SIS.

Trial registration

IRCT20190121042445N1, Registered 19 February 2019.

The plausible role of Deep Cervical Fascia and its continuum in chronic craniofacial and Cervicobrachial Pain: A case report

Background

The painful conditions of the Upper quarter region (UQR) such as chronic Craniofacial Pain (CFP) and Cervicobrachial Pain (CBP) usually occur with a plethora of symptoms. Although biological and psychosocial factors are attributed to such conditions, the involvement of the Deep Cervical Fascia (DCF) is ambiguous and needs further exploration.

Objective

We reported a case of CFP and CBP with an intent to showcase the possible involvement of impaired DCF in such presentations and to explore the short-term effect of Fascia directed approach (Fascial Manipulation).

Methods

This is a report of a 25-year-old female college student with chronic head, temporomandibular, neck, and arm pain over the past four years with acute pain exacerbation. After identifying the densified Centre of Coordination points along the myofascial continuum of the DCF, Fascial Manipulation (FM) was performed by deep manual friction. The patient-reported outcomes such as the Numerical Pain Rating Scale (NPRS), Temporomandibular disability index (TMDI), and Patient-Specific Functional Scale (PSFS) were assessed.

Results

Following FM treatment, there is a reduction in pain and improved function between the baseline and follow up evaluation after one week based on all the outcomes (NPRS, PSFS, and TMDI).

Conclusion

This case report highlights the possible role of dysfunction of the DCF and the importance of assessing myofascial chains in patients with pain in the UQR. The report has also shown that FM may be beneficial and can be considered an adjunct in the rehabilitation of chronic CFP and CBP. Nevertheless, future studies with multiple sessions and follow-ups are imperative.

Short-term Response to Treatment Targeting the Thoracolumbar Junction in Patients With Hip Pain: A Case Series

BACKGROUND

In patients presenting with hip and groin symptoms, evaluation and treatment of the thoracolumbar junction (TLJ) may be underutilized. The TLJ is less recognized as a source of pain referral in these regions. The purpose of this case series was to describe the management of 3 patients with primary hip and groin pain who were treated with interventions targeting the TLJ.

DIAGNOSIS

The 3 patients in this case series presented with subacute or chronic complaints of hip and groin pain that had failed to resolve with typical treatments. They had undergone several inconclusive clinical testing procedures. Each patient underwent a detailed physical therapy evaluation and was found to have pain and mobility deficits at the TLJ. Once the therapist had determined that the patients' symptoms were likely of musculoskeletal origin, treatment commenced. Joint mobilization and exercise directed at the TLJ were used in each case. Marked improvements in pain, thoracic range of motion, and functional deficits were observed within 3 to 4 weeks, after an average of 6 treatment sessions. All patients returned to prior activity levels. Patients in cases 1 and 3 had improvements in hip mobility and strength without direct treatment to the hip.

DISCUSSION

This case series describes the management of 3 patients with hip and groin symptoms who were successfully treated with interventions targeting the TLJ. In patients reporting primary hip or groin pain, physical therapists should consider the TLJ as a potential source of symptoms and include treatment strategies directed at the TLJ, as warranted, after a careful examination and clinical-reasoning process.

LEVEL OF EVIDENCE

Differential diagnosis, level 4. J Orthop Sports Phys Ther 2019;49(8):611-619. doi:10.2519/jospt.2019.8309.

Side-to-side elbow range of movement variability in an ulnar neurodynamic test sequence variant in asymptomatic people

Background:

Range of motion (ROM) asymmetry between sides is one indicator of a positive neurodynamic test, but this has been less well studied for the ulnar nerve.

Objective:

The purpose of this study was to investigate side-to-side variation in elbow ROM during an ulnar neurodynamic test sequence, including contralateral cervical side flexion, in 40 asymptomatic subjects.

Methods:

A traditional goniometer was used to measure elbow flexion ROM at two end points, onset of resistance (R1) and symptom onset (P1). Two repeated measures of R1 and P1 were taken on each side.

Results:

Reliability for R1 and P1 was found to be good (ICC ≥0.83, SEM ≤5.37) with no significant difference in mean ROM between sides. A significant relationship between sides was seen (r values ≥0.48) and R2 values >0.23; this indicates at least 23% of the variance observed in one limb was accounted for by range in the opposite limb. This relationship was slightly stronger for R1 than P1. Lower bound scores indicate that intra-individual ROM difference >23° for R1 and 22^° for P1 would exceed normal ROM asymmetry.

Conclusion:

These findings provide clinicians with background information of ROM asymmetry during the ulnar neurodynamic test.

The Design, Development, and Reliability Testing of a New Innovative Device to Measure Ankle Joint Dorsiflexion

BACKGROUND

In clinical and research settings, ankle joint dorsiflexion needs to be reliably measured. Dorsiflexion is often measured by goniometry, but the intrarater and interrater reliability of this technique have been reported to be poor. Many devices to measure dorsiflexion have been developed for clinical and research use. An evaluation of 12 current tools showed that none met all of the desirable criteria. The purpose of this study was to design and develop a device that rates highly in all of the criteria and that can be proved to be highly reliable.

METHODS

While supine on a treatment table, 14 participants had a foot placed in the Charles device and ankle joint dorsiflexion measured and recorded three times with a digital inclinometer. The mean of the three readings was determined to be the ankle joint dorsiflexion.

RESULTS

The analysis used was intraclass correlation coefficient (ICC). There was very little difference in ICC single or average measures between left and right feet, so data were pooled (N = 28). The single-measure ICC was 0.998 (95% confidence interval, 0.996-0.998). The average-measure ICC was 0.998 (95% confidence interval, 0.995-0.999). Limits of agreement for the average measure were also very good: -1.30° to 1.65°.

CONCLUSIONS

The Charles device meets all of the desirable criteria and has many innovative features, increasing its appropriateness for clinical and research applications. It has a suitable design for measuring dorsiflexion and high intrarater and interrater reliability.

A study of wrist pain in industry — theories of causation

Arm pain has been reported in industry as a major reason for absence, particu larly amongst those whose jobs are heavy or repetitive. The purpose of this study was to identify the precise anatomical sites and nature of the conditions affecting industrial subjects. A modular physical examination was devised with an introductory module performed 'blind' to minimize bias, and a series of optional sub-modules to cope with the great variety of conditions.

The results of the examination of 332 subjects (220 with arm pain and 112 with none) demonstrated joint dysfunctions in 60% of 70 subjects reporting wrist pain. Some 20% of the wrist joint dysfunctions were 'hidden', which may explain the reports of 'nil findings'. In contrast to this there were lower than expected frequencies of tendinitis, tenosynovitis and carpal tunnel syndrome.

Theories of causation are discussed together with the implications for industry, and suggestions are made for assessment procedures.

Addressing neurodynamic irritability in a patient with adhesive capsulitis: a case report

BACKGROUND

Patients with adhesive capsulitis are commonly seen by physical therapists. Pain and limited shoulder motion from adhesive capsulitis have at times been linked to neural irritation. The purpose of this case is to describe the examination and intervention of a patient with adhesive capsulitis who appeared to have a coexisting, underlying neural irritation. This paper emphasizes how the neurological component must initially be identified and addressed for a successful outcome.

CASE DESCRIPTION

A 47-year-old female presented with reduced shoulder motion and function, upper extremity neural irritation, diffuse weakness, altered sensation in the involved extremity, and symptoms reproduced with upper limb neurodynamic testing. Her reduced shoulder range of motion was accompanied by limited glenohumeral glides and a report of local neck stiffness. Symptoms began several months earlier after an apparent electrical shock injury to the arm that caused symptoms and guarding of the shoulder. Intervention initially addressed the underlying neural component with spinal mobilizations while avoiding further irritation. Interventions were progressed to include mobilization and exercise to address shoulder mobility.

OUTCOMES

The patient's neurodynamic irritability, distal symptoms, and neck stiffness were normalized within the first weeks of care. Subsequently, interventions were directed at the shoulder. Outcomes over an 12-week time frame included reduced pain from 10/10 to 2/10. Passive range of motion increases included flexion from 121 to 160°, abduction from 71 to 121°, and external rotation from 18 to 60°. Disability scores on Disabilities of the Arm, Shoulder, and Hand (DASH) dropped from initially 68·3 to 18·3% at discharge. She ultimately regained full upper extremity function.

DISCUSSION

Therapists should be cognizant of possible neural irritation in shoulder disorders, which may contribute to conditions such as adhesive capsulitis. Identifying neural irritation is critical when determining which interventions will achieve optimal outcomes without aggravating the condition.

Neural mobilization promotes nerve regeneration by nerve growth factor and myelin protein zero increased after sciatic nerve injury

Neurotrophins are crucial in relation to axonal regrowth and remyelination following injury; and neural mobilization (NM) is a noninvasive therapy that clinically is effective in neuropathic pain treatment, but its mechanisms remains unclear. We examined the effects of NM on the regeneration of sciatic nerve after chronic constriction injury (CCI) in rats. The CCI was performed on adult male rats, submitted to 10 sessions of NM, starting 14 days after CCI. Then, the nerves were analyzed using transmission electron microscopy and western blot for neural growth factor (NGF) and myelin protein zero (MPZ). We observed an increase of NGF and MPZ after CCI and NM. Electron microscopy revealed that CCI-NM samples had high numbers of axons possessing myelin sheaths of normal thickness and less inter-axonal fibrosis than the CCI. These data suggest that NM is effective in facilitating nerve regeneration and NGF and MPZ are involved in this effect.

Radial nerve mobilization reduces lateral elbow pain and provides short-term relief in computer users

Study Design :

Prospective Experimental Study.

Background :

Computer users may be at risk of lateral elbow pain. It is theorized that adverse mechanical tension can arise in the radial nerve with sustained keyboarding due to sustained static work of the elbow extensor muscles. Neural mobilization has been suggested as a potential treatment.

Purpose :

The purpose of this study was to evaluate the effect of neural mobilization of the radial nerve on a single occasion in terms of its ability to reduce lateral elbow pain.

Methods and Analysis :

Forty-one computer professionals (Mean age 46.7; S.D. 12.77), who had experienced lateral elbow pain for a mean of 2.87 months were recruited. The participants rated the pain using a verbal, numeric rating scale (NRS). Radial nerve tension was tested using the Upper limb Tension Test (ULTT) for radial nerve in both upper extremities. The radial nerve was mobilized using a series of 8 oscillations and repeated 3 times with a one minute rest in between. The NRS and ULLT were repeated after treatment and the scores compared using a paired t-test by the first author.

Results :

The mean NRS scores decreased significantly from 5.7 (1.1) to 3.8 (1.4) (p<0.000; t value=8.07).

Conclusion :

A single session of 3 neural mobilization resulted in a reduction of pain in computer users with lateral elbow pain. A long-term randomized trial is needed to determine the effects sustained over-time.

Effect of glenohumeral forward flexion on upper limb myoelectric activity during simulated mills manipulation; relations to peripheral nerve biomechanics

BACKGROUND

It is generally accepted that muscles may activate via the common nociceptive flexion reflex (NFR) in response to painful stimuli associated with tensile or compressive forces on peripheral nerves. Following the basic assumption that the radial nerve may be stressed around the elbow during the execution of the Mills manipulation, two positions considered to have different mechanical effects on the radial nerve and the brachial plexus were tested in order to i) explore whether muscles are activated in certain patterns with concomitant changes in nerve tension, ii) establish whether muscle responses can be modified with mechanical unloading of the brachial plexus.

METHODS

Muscle responses were quantified bilaterally in eight subjects (N = 16) during Mills Manipulation (MM) pre-manipulative positioning and a Varied position that putatively produces less mechanical tension in the brachial plexus. End range pre-manipulative stretch was used in order to simulate the effects of Mills manipulation. Electromyographic signals were recorded with a 16 channel portable EMG unit and correlated with kinematic data from three charge-coupled device adjustable cameras which allowed for precise movement tracking.

RESULTS

Compared with the Standard Mills manipulation position, the Varied position produced significantly reduced myoelectric activity (P ≤ .001) in all test muscles. Additional subjective data support the notion that certain muscle activity patterns were protective.

CONCLUSION

It seems that protective muscles are selectively activated in a specific pattern in order to protect the radial nerve from mechanical tension by shortening its pathway, suggesting integration of muscle and neural mechanisms. Furthermore, the significantly decreased myoelectric activity with reduced mechanical tension in the brachial plexus may help controlling collateral effects of the Mills manipulation itself, making it potentially safer and more specific.

Neural mobilization reverses behavioral and cellular changes that characterize neuropathic pain in rats

BACKGROUND

The neural mobilization technique is a noninvasive method that has proved clinically effective in reducing pain sensitivity and consequently in improving quality of life after neuropathic pain. The present study examined the effects of neural mobilization (NM) on pain sensitivity induced by chronic constriction injury (CCI) in rats. The CCI was performed on adult male rats, submitted thereafter to 10 sessions of NM, each other day, starting 14 days after the CCI injury. Over the treatment period, animals were evaluated for nociception using behavioral tests, such as tests for allodynia and thermal and mechanical hyperalgesia. At the end of the sessions, the dorsal root ganglion (DRG) and spinal cord were analyzed using immunohistochemistry and Western blot assays for neural growth factor (NGF) and glial fibrillary acidic protein (GFAP).

RESULTS

The NM treatment induced an early reduction (from the second session) of the hyperalgesia and allodynia in CCI-injured rats, which persisted until the end of the treatment. On the other hand, only after the 4th session we observed a blockade of thermal sensitivity. Regarding cellular changes, we observed a decrease of GFAP and NGF expression after NM in the ipsilateral DRG (68% and 111%, respectively) and the decrease of only GFAP expression after NM in the lumbar spinal cord (L3-L6) (108%).

CONCLUSIONS

These data provide evidence that NM treatment reverses pain symptoms in CCI-injured rats and suggest the involvement of glial cells and NGF in such an effect.

Common interlimb asymmetries and neurogenic responses during upper limb neurodynamic testing: implications for test interpretation

STUDY DESIGN

Clinical measurement pilot study.

INTRODUCTION

Upper limb neurodynamic testing (ULNT1) uses interlimb comparisons to investigate nerve sensitivity to movement.

PURPOSE OF THE STUDY

To establish the magnitude of range of motion asymmetries between limbs and the frequency of neurogenic sensory responses during ULNT1.

METHODS

Elbow extension range of motion (EE-ROM) and sensory responses were measured during ULNT1 in dominant and nondominant limbs for 40 asymptomatic participants. Structural differentiation was performed to examine if sensory responses were associated with neurogenic sources.

RESULTS

The average intraindividual EE-ROM asymmetry was 7.28 deg (6.68 standard deviation) (95% confidence interval: 5.18, 9.28). Sensory responses in the limbs during ULNT1 were altered by structural differentiation in 95% of participants. An intraindividual, interlimb difference of ≥10 deg exceeds the range of common asymmetry during ULNT1.

CONCLUSIONS

Neurogenic sensory responses are common findings in healthy individuals and should be acknowledged when interpreting ULNT1 findings.

LEVEL OF EVIDENCE

3a.

Pain catastrophizing predicts pain intensity during a neurodynamic test for the median nerve in healthy participants

Psychological factors within the Fear-Avoidance Model of Musculoskeletal Pain (FAM) predict clinical and experimental pain in both symptomatic and asymptomatic individuals. Clinicians routinely examine individuals with provocative testing procedures that evoke symptoms. The purpose of this study was to investigate which FAM factors were associated with evoked pain intensity, non-painful symptom intensity, and range of motion during an upper-limb neurodynamic test. Healthy participants (n = 62) completed psychological questionnaires for pain catastrophizing, fear of pain, kinesiophobia, and anxiety prior to neurodynamic testing. Pain intensity, non-painful sensation intensity, and elbow range of motion (ROM) were collected during testing and served as dependent variables in separate simultaneous regression models. All the psychological predictors in the model accounted for 18% of the variance in evoked pain intensity (p = .02), with only pain catastrophizing (beta = .442, p < .01) contributing uniquely to the model. Psychological predictors did not explain significant amounts of variance for the non-painful sensation intensity and ROM models. These findings suggest that pain catastrophizing contributed specifically to evoked pain intensity ratings during neurodynamic testing for healthy subjects. Although these findings cannot be directly translated to clinical practice, the influence of pain catastrophizing on evoked pain responses should be considered during neurodynamic testing.

Impact of order of movement on nerve strain and longitudinal excursion: a biomechanical study with implications for neurodynamic test sequencing

It is assumed that strain in a nerve segment at the end of a neurodynamic test will be greatest if the joint nearest that nerve segment is moved first in the neurodynamic test sequence. To test this assumption, the main movements of the median nerve biased neurodynamic test were applied in three different sequences to seven fresh-frozen human cadavers. Strain and longitudinal excursion were measured in the median nerve at the distal forearm. Strain and relative position of the nerve at the end of a test did not differ between sequences. The nerve was subjected to higher levels of strain for a longer duration during the sequence where wrist extension occurred first. The pattern of excursion was different for each sequence. The results highlight that order of movement does not affect strain or relative position of the nerve at the end of a test when joints are moved through comparable ranges of motion. When used clinically, different neurodynamic sequences may still change the mechanical load applied to a nerve segment. Changes in load may occur because certain sequences apply increased levels of strain to the nerve for a longer time period, or because sequences differ in ranges of joint motions.

Effects of upper extremity neural mobilization on thermal pain sensitivity: a sham-controlled study in asymptomatic participants

STUDY DESIGN

A single-blinded, quasi-experimental, within- and between-sessions assessment.

OBJECTIVES

To investigate potential mechanisms of neural mobilization (NM), using tensioning techniques in comparison to sham NM on a group of asymptomatic volunteers between the ages of 18 and 50.

BACKGROUND

NM utilizing tensioning techniques is used by physical therapists in the treatment of patients with cervical and/or upper extremity symptoms. The underlying mechanisms of potential benefits associated with NM tensioning techniques are unknown.

METHODS AND MEASURES

Participants (n = 62) received either a NM or sham NM intervention 2 to 3 times a week for a total of 9 sessions, followed by a 1-week period of no intervention to assess carryover effects. A-delta (first pain response) and C-fiber (temporal summation) mediated pain perceptions were tested via thermal quantitative sensory testing procedures. Elbow extension range of motion (ROM) and sensory descriptor ratings were obtained during a neurodynamic test for the median nerve. Data were analyzed with repeated-measures analysis of variance (ANOVA).

RESULTS

No group differences were seen for A-delta mediated pain perception at either immediate or carryover times. Group differences were identified for immediate C-fiber mediated pain perception (P = .032), in which hypoalgesia occurred for the NM group but not the sham NM group. This hypoalgesic effect was not maintained at carryover (P = .104). Group differences were also identified for the 3-week and carryover periods for elbow extension ROM (P = .004), and for the participant sensory descriptor ratings (P = .018), in which increased ROM and decreased sensory descriptor ratings were identified in participants in the NM group but not the sham NM group.

CONCLUSION

This study provides preliminary evidence that mechanistic effects of tensioning NM differ from sham NM for asymptomatic participants. Specifically, NM resulted in immediate, but not sustained, C-fiber mediated hypoalgesia. Also, NM was associated with increased elbow ROM and a reduction in sensory descriptor ratings at 3-week and carryover assessment times. These differences provide potentially important information on the mechanistic effects of NM, as well as the description of a sham NM for use in future clinical trials.

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.

Hamstring injury management--Part 2: Treatment

The management of hamstring injuries can be described as vexed at best. One reason for this may be because of a lack of high-quality research into the methods of treatment, rehabilitation and prevention. As a result, an evidence-based approach to injury management does not exist. Management is based on clinical experience, anecdotal evidence and the knowledge of the biological basis of tissue repair. Previous hamstring injury is the most recognized risk factor for injury, which indicates that treatment approaches may be suboptimal under certain conditions. The identification of these risk factors and the methods best designed to manage them should be addressed with future research efforts. Much anecdotal and indirect evidence exists to suggest that several non-local factors contribute to injury. Despite the knowledge that these factors may exist, the literature appears almost devoid of research investigating their possible identification and treatment. Treatment has traditionally been in the form of altering the muscle repair process through the application of electrophysical therapy and various soft-tissue-based and exercise-based techniques. Little research has investigated the role of other forms of manual therapy particularly when directed at non-local structures. This paper will explore and speculate on this potential connection and offer some new contributive factors for hamstring injury management.

Strain and excursion in the rat sciatic nerve during a modified straight leg raise are altered after traumatic nerve injury

PURPOSE

This study investigated the biomechanics of the sciatic nerve with hind limb positioning in live and euthanized Sprague-Dawley rats after traumatic nerve injury.

METHODS

With radiographic analysis, sciatic nerve excursion and strain were measured in situ during a modified straight leg raise, which included sequential hip flexion and ankle dorsiflexion. Comparisons were made between nerves in uninjured, sham-injured and mild crush-injured rats at the 7-day and 21-day recovery times.

RESULTS

Significant strain and proximal excursion of the sciatic nerve were observed in all groups during hip flexion, and additional increased strain was noted during dorsiflexion. Seven days after nerve injury, strain increased significantly during hip flexion (17.64+/-14.12%; p=0.0091) and dorsiflexion (22.56+/-15.47%; p=0.0082) compared to the sham-injured controls. At 21 days after injury, the strains were similar between the injured and sham-injured groups.

CONCLUSIONS

Nerve bed elongation during straight leg raise causes sciatic nerve strain and excursion towards the moving joint with the greatest movement nearest the moving joint. In the first week after injury, the maximal strain exceeded the level previously shown to impair nerve conduction and circulation.

Reliability of detecting 'onset of pain' and 'submaximal pain' during neural provocation testing of the upper quadrant

BACKGROUND AND PURPOSE

Conflicting results have been reported with regard to the reliability of neural tissue provocation tests and it is unclear whether repeated testing affects the test results. In the present study, the stability and reliability of the occurrence of 'onset of pain' and 'submaximal pain' throughout the range of motion during neurodynamic testing was analysed, in both a laboratory and a clinical setting.

METHOD

A repeated-measures study design within and between sessions was used. In the laboratory and clinical settings, the base neurodynamic test for the median nerve was performed during a single session on a total of 27 patients with neurogenic cervico-brachial pain. In addition, the base test and three common variations were performed on two occasions by two examiners on 10 asymptomatic subjects in laboratory conditions only. Patients indicated the moment of 'submaximal pain' occurrence, whereas asymptomatic subjects indicated 'onset of pain' and 'submaximal pain'. Corresponding angles at the elbow were recorded by use of an electrogoniometer.

RESULTS

In the asymptomatic group, the intra- and inter-tester reliability within the same session was excellent (intraclass correlation coefficient (ICC2.1 > or = 0.95; standard error of measurement (SEM) < or = 4.9 degrees). Reliability after a 48-hour interval was moderate (ICC2.1 > or = 0.69; SEM < or = 9.9 degrees). The reliability coefficients for the symptomatic group within the same session were comparable with the excellent results of the asymptomatic group, for both the laboratory (ICC2.1 = 0.98; SEM = 2.8 degrees) and clinical settings (ICC2.1 > or = 0.98; SEM < or = 3.4 degrees). Consequently, from a statistical perspective, improvements in range of motion as small as approximately 7.5 degrees may be interpreted meaningfully. No significant trend due to repeated testing could be observed when three consecutive repetitions were analysed.

CONCLUSIONS

Pain provocation during neurodynamic testing is a stable phenomenon and the range of elbow extension corresponding with the moment of 'pain onset' and 'submaximal pain' may be measured reliably, both in laboratory and clinical conditions.

Physiotherapy in palliative oncology

Outreach multi-disciplinary palliative care teams have tended to duplicate hospital-based teams which historically have consisted almost exclusively of doctors and nurses. This paper outlines the role of physiotherapy in palliative care. It provides a conceptual framework for physiotherapy involvement and its potential to contribute within the palliative care team therapeutically and cost-effectively. To put physiotherapy management of the disease process into perspective, some basic data on terminal illness, and statistics of a Brisbane hospice, are included. The need for more outreach physiotherapy intervention is emphasised.

The response to the slump test in a group of female whiplash patients

This study was undertaken to assess the difference between the response to the slump test in 40 asymptomatic and 20 symptomatic female subjects with cervical pain after whiplash injury. Areas and alterations of pain responses during the test, and ranges of movement of knee extension, were analysed. The results demonstrated that the addition of knee extension and left ankle dorsiflexion during the slump test produced a significant increase in the intensity of comparable cervical symptoms in the whiplash group. The whiplash group also showed a greater limitation in knee extension range of movement during the test than did the control group. These differences suggest that pathological changes of the neural system itself or adjacent tissues, affecting the mechanics of the neural system, may be a contributing factor to these patients' cervical symptoms.

Pain and muscular responses to a neural tissue provocation test in the upper limb

Pain and muscular responses to a Neural Tissue Provocation Test with bias to median nerve were examined in 20 asymptomatic subjects. The test was performed on both arms with the cervical spine in a neutral position and in contralateral sideflexion as a sensitizing manoeuvre. The angle of elbow extension at the time of onset of pain and muscle activity in trapezius, biceps and triceps muscles was measured using an electrogoniometer. Muscle activity was recorded by surface electromyography. Results indicate that pain responses and muscle activity of trapezius are present in the majority of normal subjects. The onset of pain was highly reliable and compared favourably with detection of muscle activity onset. There was no significant difference of the angle of the elbow with the onset of pain between arms. Hence in patients with unilateral neck or upper limb pain a difference between sides might be indicative of a possible neural tissue involvement. Pain and muscular responses were influenced by the position of the cervical spine. This finding suggests that cervical contralateral sideflexion has a sensitizing effect on neural tissues. There was an association between the onset of pain and onset of trapezius muscle activity in all painful trials. However, muscle activity was also present in subjects with no pain.

Addition of test components during neurodynamic testing: effect on range of motion and sensory responses

STUDY DESIGN

Single session, repeated-measures design.

OBJECTIVES

To analyze the impact of different components of the neural tissue provocation test for the median nerve (NTPT1) on the range of motion (ROM) of the elbow and wrist and the sensory responses elicited by the test.

BACKGROUND

The assessment of minor peripheral nerve injuries by neurodynamic tests is becoming more integrated in physical therapy practice. The influence of different test components on the nervous system has been analyzed in numerous in vitro studies, but in vivo studies are still lacking.

METHODS AND MEASURES

Five test variations were performed on 35 asymptomatic men (23.5 +/- 2.3 years). Elbow extension was performed (1) without additional components (NTPT1NEUTRAL), (2) with wrist extension (NTPT1WE), (3) with cervical contralateral lateral flexion (NTPT1CLLF), and (4) with both wrist extension and cervical contralateral lateral flexion (NTPT1WE+CLLF). In the fifth variant, the wrist was extended from a preloaded position (WENTPT1). The range of elbow and wrist extension when a submaximal discomfort was elicited was measured with 2 electrogoniometers.

RESULTS

The addition of each test component resulted in a significantly reduced ROM (NTPT1NEUTRAL: 179.5 +/- 8.8 degrees, NTPT1WE: 169.0 +/- 13.9 degrees, NTPT1CLLF: 154.7 +/- 13.2 degrees, NTPT1WE+CLLF: 143.9 +/- 16.1 degrees; WENTPT1: 67.1 +/- 11.0 degrees). Sensory responses were predominantly evoked at the region of the added component.

CONCLUSIONS

The different test components, whose mechanical influence on the nervous system has been demonstrated in anatomical studies, also have an effect on joint ROM and sensory responses during neurodynamic testing, when individually or simultaneously added. If the nerve bedding is elongated throughout its whole length, the available ROM is markedly reduced and sensory responses can be elicited throughout the entire arm.

Shoulder girdle elevation during neurodynamic testing: an assessable sign?

One of the signs advocated for monitoring during neurodynamic testing in the assessment of patients with upper quadrant disorders, is the response of the shoulder girdle. It is stated that a protective rising of the shoulder girdle is present when patients with neurogenic disorders are assessed and that the elevation is absent in asymptomatic subjects. As sensory responses are elicited in the majority of asymptomatic subjects and as the range of motion (ROM) is often limited during neurodynamic testing, it is questionable whether the elevation of the shoulder girdle would be absent in asymptomatic subjects. The aim of this study was to measure the shoulder girdle elevation force during five variants of the neural tissue provocation test for the median nerve. Thirty-five asymptomatic male subjects were assessed. A load cell was used to measure the amount of shoulder girdle elevation force and two electrogoniometers were used to measure the ROM at the elbow and wrist. When the ROM at the end of the test was restricted, a gradual increase in shoulder girdle elevation force could be observed throughout the test. Compared to the initial force at the start of the test, all variants resulted in a significant increase in force. It is concluded that a gradual increase in shoulder girdle elevation force should not be regarded as an abnormal sign in the interpretation of neurodynamic tests.

Examination and treatment of a patient with hypermobility syndrome

BACKGROUND AND PURPOSE

The purpose of this case report is to present the patient examination, evaluation/diagnosis/prognosis, intervention, and outcome of a patient with hypermobility syndrome (HMS). Hypermobility syndrome has been widely recognized in the rheumatology literature, but it has seldom been discussed in the orthopedic literature and has only recently been described in the physical therapy literature. The signs and symptoms of HMS are common among patients seen in orthopedic physical therapy clinics; however, the underlying HMS may be overlooked while treating individual joints or tissues causing pain. CSE DESCRIPTION: The patient was a 28-year-old woman with complaints of chronic, multiple-joint pain. After years without a diagnosis, a rheumatologist had recently diagnosed underlying HMS.

OUTCOMES

Following intervention that emphasized patient education and activity modification, the patient's complaints decreased.

DISCUSSION

Recognition of HMS underlying common orthopedic problems may facilitate appropriate patient education and management.

Use of lumbar extension, slump test, physical and neurological examination in the evaluation of patients with suspected herniated nucleus pulposus. A prospective clinical study

This prospective and consecutive study was designed to evaluate the validity of different clinical tests, e.g. lumbar extension in lying and slump test for patients with suspected herniated nucleus pulposus, in comparison with findings on computed tomography (CT) and/or magnetic resonance imaging (MRI) scan. There were 105 patients who were seen and examined by the senior author (for the sake of the study) at the Orthopaedic Physiotherapy Department, on an average of 5.5 days (range 0-21 days) before CT and/or MRI examination were carried out. There were 36 women and 69 men with an average age of 42.7 +/- 9.8 (range 19-64) years. According to the radiological findings on CT and/or MRI, the patients were divided into three groups: 52 patients with disc hernia, 41 patients with bulging discs and 12 patients without positive findings. The mean values with standard deviations of 25 variables of three diagnostic groups were studied. Multiple comparison adjustment according to Bonferroni showed significant differences for three variables that were of diagnostic value (lumbar range of motion for forward flexion, left side-bending in standing, and pain distribution during extension in standing). The agreement between clinical and radiological findings for type and level of diagnosis of disc herniation was accurate in 72 patients (69%). The diagnostic sensitivity for disc herniation was 82.6% and the specificity 54.7%.

Assessing Adverse Neural Tension in Athletes

Sports medicine assessment and treatment techniques are ever developing and becoming more holistic. Traditional musculoskeletal assessment is changing to incorporate neural tissue pathology. Neural tension tests assess the mobility of neural tissue in the extremities and spinal canal. Positive adverse neural tension tests suggest poor mobility of neural tissue. Athletes with adverse neural tension often present with pain and decreased range of motion. These disorders can occur individually or can be associated with sports injuries. Ankle sprains, hamstring strains, tennis elbow, and thoracic outlet syndrome are some conditions that respond well to treatment of adverse neural tension. Reports of improved treatment outcomes following neural tension assessment and treatment suggest that adverse neural tension should be considered as a possible source of pain and dysfunction. This paper outlines concepts necessary to understand adverse neural tension including neuroanatomy, pathology, assessment techniques, and common sports injuries that may have an adverse neural tension component.

Adverse neural tension: a factor in repetitive hamstring strain?

The etiology and nature of repetitive hamstring strain is complex and not fully understood. The purpose of this study was to investigate the presence of adverse neural tension in 14 male Rugby Union players with a history of grade 1 repetitive hamstring strain. Comparison was made to an injury-free matched control group. Adverse neural tension was assessed using the slump test. Hamstring flexibility was measured using the active knee extension in lying test. Results indicated that 57% of the test group had positive slump tests, suggesting the presence of adverse neural tension. None of the control group had a positive slump test. Analysis of variance revealed no differences in flexibility between groups or between those demonstrating a positive or negative slump test. Results suggest that adverse neural tension may result from or be a contributing factor in the etiology of repetitive hamstring strain. Residual decreased flexibility is not apparent in this subject group.

The slump test: the effects of head and lower extremity position on knee extension

Maitland's slump test is a widely used neural tissue tension test. During slump testing, terminal knee extension is assessed for signs of restricted range of motion (ROM), which may indicate impaired neural tissue mobility. A number of refinements that modify hip and ankle position has been added to the basic slump test procedure, but no research to date has measured the effects of ankle and hip position on knee extension ROM during testing. The purpose of this study was to examine the effect of neural tension-producing movements of the cervical spine and lower extremity on knee extension ROM during the slump test. Thirty-four males with no significant history of low back pain were tested in the slump position with the cervical spine flexed and extended in each of three lower extremity test positions: neutral hip rotation with the ankle in a position of subject comfort (neutral), neutral hip rotation with ankle dorsiflexion (ankle dorsiflexion), and medial hip rotation with ankle dorsiflexion. Results showed significant decreases in active knee extension ROM (F1,198 = 29.53, p < 0.0001) in the cervical flexion compared with the cervical extension conditions. Subjects also exhibited significant decreases in active knee extension ROM (F2,198 = 56.76, p < 0.0001) as they were progressed from neutral to the ankle dorsiflexion to the medial hip rotation with ankle dorsiflexion positions of the lower extremity. The results of our study indicate that limitations in terminal knee extension ROM may be considered a normal response to the inclusion of cervical flexion, ankle dorsiflexion, or medial hip rotation in the slump test in young, healthy, adult males. In addition, the presence of a cumulative effect on knee extension ROM with the simultaneous application of these motions is noted. These findings may assist clinicians when assessing knee extension ROM during slump testing.

Persistent mechanical allodynia following injury of the hand. Treatment through mobilization of the nervous system

Mechanical allodynia (MA) following hand injury is a well-documented clinical problem. The purpose of this pilot study was to examine the relationship between hand MA and the upper limb tension test (ULTT). The ULTT mechanically stresses the neural structures from the C5/6/7 neural foramina to the median nerve distally. This study examined 29 subjects with unilateral hand MA before and after a 2-week neural self-mobilization programme. There was a significant difference between the subjects' affected and unaffected sides when tested using the ULTT, both in reproduction of symptoms and in reduced range of motion of the ULTT. Following the self-mobilization program, there was an improvement in the range of the ULTT, and subjects reported a reduction in their symptoms. Complete recovery was not obtained in all cases. The results of this study suggest that the ULTT is a useful tool both in assessment and treatment of subjects with hand MA.