Neurodynamics

Question 1

Definition of neurodynamics

Answer 1

Clinical application of mechanics and physiology of the NS as they relate to each other and are integrated with musculoskeletal function

Question 2

Neurodynamic Tests

Answer 2

Examine contribution of spinal nerve roots and peripheral nerves to extremity pain

• Sequential lengthening of distance the dura travels
• Controlled mechanical stresses to the dura and other neurologic tissues

Question 3

_____ _____ placed on the dura of the spinal nerve roots and the peripheral nerve roots until ____

Answer 3

Tensile stresses

Until the patient’s symptoms are reproduced

Question 4

Purpose of neurodynamics

Answer 4

to test for neurologic component to the symptoms

Pathological mechanosensitivity of the nervous system (are the nerves hypersensitive to movement)

Question 5

Mechanical

Answer 5

What is the nerve doing
Tension - lengthen distance it travels
Sliding - is it gliding as it should
Compression - is something pushing on it

Question 6

Physiological

Answer 6

Intra-neural blood flow
Inflammation
Mechano-sensitivity (nerve responding to movements)

Question 7

Causes of neurodynamic pathology

Answer 7

1. Mechanical
2. Vascular
3. Axoplasmic

Question 8

Mechanical cause

Answer 8

Inc in length neural structures travel

• nerve excursion during extremity movements (tension sites/adherent) - nerve isn’t gliding well
• Pathologic (tumor, disc, osteophyte)
• Musc or articular dysfunction (capsular connection to dura)
• Fibrosis (chronic nerve root adhesion)

Question 9

Vascular cause

Answer 9

Swelling, ischemia
Hypoxia, increased intraneural pressure
Physiology is not working properly

Question 10

Axoplasmic cause

Answer 10

Changes with blood flow

• Dec nerve function at cellular level
• Structural alterations (demyelination)
• Abnormal impulses at DRG

Question 11

Neurodynamic Dysfunction

Answer 11

Nerve trunks exhibit mechanial allodynia

Hypersensitivity of the nervous system

Question 12

Muscle role

Answer 12

Muscles have a sifignificant role in protection of neural tissues when they are inflamed or hypersensitive to movement –> it will inc muscle tone so as to prevent the nerve from having to lengthen
More of the physiologic than mechanical

Question 13

Subjective complaitns

Answer 13

1. Extremity weakness/heaviness
2. Numbness or tingling
3. Swelling (may not be visibly swollen though)
4. Pain - burning, aching, vague
5. “lines” or “clumps” or pain
6. Aggravated by positions that inc distance nerve travels

Question 14

Neurodynamic Examination tests

Answer 14

Slump test

Straight leg raise

Question 15

Normal test (without any neurodynamic issue)

Answer 15

tingling
stretch
maybe an ache

Question 16

Positive neurodynamic test

Answer 16

Reproduces their comparable sign
Test response altered by distant movement (dorsiflex ankle and increases back pain = abnormal)
Diff in ROM, resistance, and sx involved vs. non-involved limb
Adverse response to nerve palpation

Question 17

Diagnositc Accuracy - Straight leg raise

Answer 17

Positive if the patient reports reproduction of LBP of LE pain at 40 degrees or less
High sensitivity (if neg = probably not a neuro problem)
SNNOUT

Question 18

Diagnositc Accuracy - Crossed SLR

Answer 18

Performed on asymptomatic side and produces symptoms in the involved LE
Higher specificity (if positive is a good indicator of a neurodynamic problem)

Question 19

Clinical Utility

Answer 19

Prone lumbar mechanical traction in patients with signs of nerve root compression
Subjects who have peripheralization with repeated lumbar extension, positive Crossed SLR
If either of those is present, they will do well with traction

Question 20

Practical handling skille

Answer 20

Joint ROM needs to be examines prior to neurodynamic exam
Think in terms of distances
- SLR
- Knee flexion/extension
- Ankle DF/PF/Inv/Ev
- Hip rotation
- Cervical flexion
Gentleness of technique is important too

Question 21

Neurodynamic Intervention - Passive oscillatory movements

Answer 21

Passive oscillatory movements

• Begin proximally with movement at the spine and moving tissues around the nerve
• Movement of anatomic structures around the neural tissue
• Movement of surrounding tissues and nerve together
• Progressive extremity positioning (adding movements that inc distance it travels)

Question 22

Neurodynamic Intervention - nerve tensioning

Answer 22

Movement of one or several joints to elongate the nerve bed and the nerve - inc nerve tension and intraneural pressure, reduces intraneural blood flow
Abnormal impulse generation –> trigger ectopic discharges, may exacerbate sx

Question 23

Neurodynamic Intervention - SLump Stretching

Answer 23

Patients with LBP and LE pain who’s distal sx do not centralize with repeated ext or flex have a positive slump test in absense of radicular sx

Question 24

Describe a slump stretch

Answer 24

Patient in long sitting with feet against a wall to maintain ankle dorsiflexion
Overpressure into cervical flexion

Question 25

Neurodynamic intervention - neural sliding

Answer 25

Elongate nerve at one joint balanced by reduction in length of nerve bed at an adjacent joint
- Nerve slides relative to surrounding structures
- Longitudinal excursion of the nerve
Dynamic variation in inta-neural pressure
- This facilitates evacuation of intra-neural edema (helps circulation and provide nutrients)
Reduces sx

Question 26

Contraindications/Precautions

Answer 26

1. Irritable conditions
2. Pathology of structures involved (bone spur - like rope starting to fray)
3. Circulatory changes
4. Malignancy
5. Neurological signs
6. Cord signs
7. Cauda equina lesions

Question 27

Symptom vs. sign

Answer 27

Symptom = subjective
Sign = objective (measurable)