For today’s chapter, I have decided that the best way to learn these tests is to show you. I will write in any pertinent details you need for a good test performance.
The Straight Leg Raise (SLR)
Add sensitizers (dorsiflexion, plantarflexion, etc) to determine nervous system involvement.
Add cervical flexion or visual input to enhance responses.
Be mindful of symptoms before and after pain responses.
If this test is positive post-operation, it will likely be inflammatory in nature.
You can preload the system further with cervical flexion or sidebending the trunk away from the test side.
Here are some other ways to perform the SLR with sensitizers first. (I apologize for the way the camera shot in advance).
For tibial nerve-bias.
For fibular nerve bias.
For sural nerve bias.
Passive Neck Flexion (PNF)
Here is how to perform the test.
Add SLR to further bias the test.
Be mindful of Lhermitte’s sign, which is an electric shock down the arms or spine. This is a must-refer sign as there is potential spinal cord damage.
Here is how to perform the slump.
Slump Knee Bend
In the book itself, Butler uses the prone knee bend as his base test. However, NOI does not teach this motion as much and now favors the slump knee bend. This movement allows for much more differentiation to be had.
And the saphenous nerve (just so you get a break from seeing me).
Have some fun with these tests, and be mindful that you are not too aggressive.
When assessing neurodynamics, there is a general system that is used including the following tests:
Passive neck flexion (PNF).
Straight leg raise (SLR).
Prone knee bend (PKB).
4 different upper limb neurodynamic tests (ULNT).
I will demonstrate these tests for you in later chapters.
Many clinicians when discussing the lower extremity-biased tests deem that maybe only one or two of the tests need to be performed, however this assertion is erroneous. Slump, SLR, and PNF all need to be tested as a cluster. The reason being is that the clinical responses may often differ.
This difference is especially noticeable when comparing the SLR and the slump. These two are not equal tests for the following reasons:
Components are performed in a different order.
Spine position is different.
Patients may be more familiar with the SLR, therefore give more familiar responses.
The patient is in control during the slump, not in the SLR.
The slump is more provocative.
Rules of Thumb
When testing neurodynamics, here are the following guidelines:
1) Active before passive.
2) Differentiate structures – add/subtract other movements to see if symptoms can change.
3) Document the test order.
The positive testing here is a little dated based on what Butler’s group and the research says as of right now. Based on what I have learned from Adriaan Louw, having any of the following is what constitutes a positive test.
Gross range of motion asymmetry between sides.
Gross sensitivity asymmetry between sides.
There are several pieces to look at when determining potential sources of neural findings.
Area: Cutaneous zones generally nerve trunk; dermatome generally nerve root.
Motor loss: Reflex loss is usually the nerve root; specific motor loss can be the root or trunk.
The neurological exam is an excellent way to sample the patient’s nervous system. When looking at the neurological system, we must realize that testing does not reflect a tissue injury alone. It demonstrates the neurological pathway’s response. There is no such thing as a focal lesion in the nervous system.
We must also understand that the exam is a very small component of a further comprehensive assessment, providing moderate diagnostic value at best. Sensitivity for a screen like this is inherently poor, meaning this examination cannot rule out nervous system pathology or involvement.
If we are going to walk the neurological walk, we first need to talk the neurological talk. Here are some important definitions.
Allodynia: Pain from a non-painful stimulus.
Hyperalgesia: Increased response to a painful stimulus.
Analgesia: No pain from a painful stimulus.
Hyperpathia: Abnormal pain reaction to a repetitive stimulus.
Hypoalgesia: Decreased response to a painful stimulus.
Hypoesthesia: Decreased sensitivity to a stimulus.
Hyperesthesia: Increased sensitivity to a stimulus.
Dysesthesia: Unpleasant, but not painful response to a stimulus.
First, we will take a look at dermatomes. Now depending on who you talk to, dermatomal levels will be different. Moreover, many people have anatomically variant dermatomes, and often times these can fluctuate throughout the day. There are however, some signature zones that are fairly consistent throughout the literature.
There are several different sensations that need to be tested. Make sure the responses include yes, no, and don’t know.
Light touch: Using a tissue, piece a cotton wool, monofilaments. It is better to use these than hands so you can be consistent. You can also just touch someone’s body hair if you are working with a hairy individual.
Superficial pain: Sharp object, dull object.
Deep pain: Often the movement exam is enough, but the Achilles can also be squeezed.
Proprioception: Finger to nose, or nose to the clinician’s finger in a constantly changing position.
The above areas target predominantly peripheral sensation, but we can also test the cortical sensory capabilities.
Graphesthesia: Identify a letter or number written on the skin.
Finger identification: Touch a patient’s finger followed by the patient touching that same finger.
Stereognosis: Identify objects by handling it.
Two-point discrimination: Tell the difference between two points and one point. Here are the distances between two points that normally can be discriminated.
Finger tips: 2-7 mm.
Palms: 8-15 mm.
Back of the hand: 20-30 mm.
Top of the foot: 30-40 mm.
Back: 40-80 mm.
There are several ways to assess motor function.
Manual muscle test: Palpate tendons while resisting to assess springiness.
Quick manual muscle test.
Median Nerve: OK sign.
Ulnar nerve: Froment’s sign.
Lower limb: Heel/toe walk.
Reflex testing looks at afferent connections and general nervous system sensitivity. However, reflexes have no correlation with muscle strength or tendon response. As a general rule, if there is reflex loss with certain conditions, prognosis is generally poorer.
Muscle-stretch reflex testing: Only until a response is elicited. There is no rationale as to why a response might fatigue.
Superficial skin: An example would be the abdominal or cremasteric reflex (look that last one up).
Central reflexes: Clonus or Babinski
Here is an example of clonus
And Babinski, normal response first.
A positive Babinski a.k.a. punt ASAP.
Here is a list of how to test each cranial nerve.
Olfactory (I): Smell identification.
Optic (II): Reading a sign with letters 20 ft away.
Oculomotor, trochlear, and abducens (III, IV, VI): Eye tracks finger movements.
Trigmeninal (V): Facial sensation; biting.
Facial (VII): Facial symmetry. Lower motor neuron lesions affect entire side of face (Bell’s Palsy). Upper motor neuron lesions affect only the lower face (stroke).
Vestibulocochlear (VIII): Hearing & balance.
Glossopharyngeal (IX): Gag reflex, numbness in back of throat.
Palpation is a major component to therapeutic touch, and gives us a way to build rapport and interact with our patients. When palpating the nervous system, it is important to palpate in sensitive positions so the nervous system is placed on load. Here are some general nerve anatomical rules.
Where a nerve has fewer fascicles and less connective tissue, palpation will be more sensitive (ulnar nerve).
Where there is a lot of connective tissue, there will be a more localized and less “nervy” response.
Where there is increased sensitivity does not mean there is damage locally. Damage could have occurred more proximally (that whole nerves fire in both directions thing).
You must also be mindful that anatomical variations are common, especially if symptoms seem anatomically weird. Here are some of the more common ones:
Martin-Gruber anastomosis: Median and ulnar communicate distally.
Rieche-Cannieu anastomosis: Deep branch of ulnar and recurrent branch of median nerve.
Absent musculocutaneous nerve.
Here are some basic nervous system palpation guidelines.
Nerves feel hard and slippery.
Palpate with your finger tip or thumb, and follow it proximally or distally.
The major premise of this book is that pain is normal. It is the way that your brain judges a situation as threatening. Even if there are problems in the body, pain will not occur if your brain thinks you are not in danger.
Explaining pain can reduce the threat value and improve pain management. And the good thing about explaining pain? Research shows that it can be an easily understood concept.
Pain is Normal
Pain from bites, postures, sprains, and other everyday activities are more often than not changes in the tissues that the brain perceives as threatening. This system is very handy, as often it keeps us from making the same mistake twice. I personally akin this to patients as recognizing a certain smell and that smell reminding you of something. Pain is often the reminder of previous injuries.
Pain becomes problematic when it becomes chronic. This pain is often the result of the brain concluding that for some reason, often a subconscious one, that the person is threatened and in danger. The trick is finding out why.
Stories are some of the best ways to relate pain to patients. There are many cases when you hear soldiers sustaining major injuries yet charging further into battle. On the flipside, take a look at paper cuts. The damage is very miniscule; however, the pain levels are huge. Point being, what occurs in the tissues is only one component of the pain experience. And if pain is not perceived, then tissue changes are not deemed threatening by the brain.
Pain oftentimes can be modified by various cues that the brain experiences called ignition cues. Take prescription drugs for example. The tablet’s shape plays a huge role in how effective the drug is.
Transparent capsules with colored beads > capsules with white beads > colored tablets > square tablets with corners missing > round tablets.
Pain is dependent on the perceived cause as well. Take someone who has survived cancer. If that person attributes a painful experience to cancer returning, the pain is often worsened regardless of what is occurring in that person’s tissues.
Lacking knowledge and understanding also increases pain and fear. We are afraid of the unknown, and if we do not know why we hurt, often the pain will increase in response to fear.
Phantom in the Body
Tissue-centric pain explanations are incomplete. The biggest example of this is phantom limb pain. The reason why these phantom limbs create pain is due to the body’s virtual representation in the brain.
The virtual body, or homunculus, is what allows us to know our body’s location in space. You access the virtual body every time you perform an action with your eyes closed. In this case of phantom limb pain, the virtual leg is still present and relates to the rest of the virtual body. This experience can even occur in children born without limbs, because that virtual representation is still present.
When a phantom limb pain occurs, the virtual leg becomes smudged. This change results in an unclear representation of the limb in the brain. This phenomenon also occurs in people who have chronic pain.
Our pain perception can often be attributed to our parents. When an infant falls, they will often look to their parents to gauge the optimal response. However, the pain experience is unique to each individual.
Overall, I thought it was an excellent course and definitely opened my mind to an approach (i.e. McKenzie) that I was not a huge fan of. I highly recommend taking one of his courses. Here were some of the pearls I got from his course. My thoughts will be italicized.
“If you don’t have a system, you are lost in an evaluation.”
When it comes to patient education, there are four things that every patient wants to know:
1) What is wrong with me?
2) How long will it take to get better?
3) What can I do for it?
4) What can you (the clinician) do for it?
When we do educate, we must not forget that pain is a biopsychosocial phenomenon and multifactorial. The onion skin model below provides a good relationship analogy for this.
The first goal addressed in education is making the patient understand pain. Patients must realize that pain is the defender, not the offender. It is our body’s way to perceive a threat. Therefore, we must quell this fear before focusing on function. Here are some suggested ways to describe pain in non-threatening ways.
When obtaining pain information from our patients, this is something that we do not have to measure. Instead, it is important to look at variables associated with pain, namely.
3) Explore how patient’s classify their symptoms (e.g. my joints are worn out), and ask why they think the symptoms still persist.
4) Consequences of the pain.
5) Coping types.
6) How the patient relates to pain (do they get angry or play the blame game).
When determining treatment course, instead of focusing on the structure at fault, look at sensitivity and function. We treat pain mechanisms, not sources. The way to classify sensitivity is by determining if the patient’s symptoms are nociceptive, peripheral neuropathic, or central-dominant. When looking at function, we look at general, specific, and mental qualities.
The Three Types of Function/Dysfunction
1) General – What are physical activity levels and favorite activities? How do their goals relate to these components?
2) Specific – Objective findings. These impairments have a heavier focus in acute pain than chronic.
3) Mental – Fear, anxiety, coping, attitude.
Your patients may have problems in one or all of these areas to one degree or another, but the biggest question a clinician must ask is if these dysfunctions are adaptive or maladaptive to pain.
Poor Outcomes 101
There are several factors that contribute to poor outcomes, many of them involving mindsets towards pain.
Belief that back pain is harmful or potentially severely disabling.
Fear-avoidance behavior and decreased activity.
Low mood and social withdrawal.
Expecting passive treatments over active participation.
Why Perform a Physical Exam
There are three reasons why you should perform the ultimate manual therapy, a physical exam:
1) Movement is how you engage the patient, and they expect it.
2) Support/reject subjective findings.
3) Allows for reassessment of patient’s problem. It helps show how you may be able to help them.
All approaches (Maitland, Mckenzie, Mulligan) have myths. The common bond between them all is pain. Today we will look at building a clinical framework with pain as the cornerstone.
Evidence-Based Medicine (EBM)
EBM is defined as a conscientious, explicit, and judicious use of current best evidence in making patient care decisions. This concept is not merely reading researches articles, but it combines scientific evidence and clinical expertise. You have to know when to apply what.
2) Evidence suggests manual therapy improvements are more psychosocial than physical.
3) A disconnect between researcher and clinician.
The researcher thinks: “What does this work contribute to the literature?”
The clinician thinks: “What does this work do for my patient?”
The movement towards outcome-based therapy per EBM is also problematic for several reasons.
1) Clinicians begin to think statistical analysis becomes greater than any other form of knowledge rather than complimentary.
2) Research doesn’t take into account the inherent uncertainty and subjectivity in a clinical encounter.
3) Good evidence can lead to bad practice if applied in uncaring and unappealing environments.
4) Outcomes may be coming out too quickly, leading to research development stopping in certain areas.
Butler’s thoughts are summed up very nicely when he states it would be a sad day if meta-analyses have the final say instead of exposing clinical errors. However, the self-scrutiny and analysis is a good thing as long as it stops short of reducing clinician self-confidence. For confidence is what allows us to practice in uncertainty and maximize the placebo effect, our most powerful pain reliever. The uncertain conditions which we practice in are what Butler terms the Grey Zone. These typify most syndromes in which underlying pathoanatomy and physiology is unknown.
Clinical Reasoning Science
Clinical reasoning involves the merging of three areas: science, current therapies, and the clinician-patient relationship.
Butler also suggests that we need to shy away from thinking damaged structures and move towards movement dysfunction. We must realize that movement sensitivity does not involve the tissues only, but is a process that involves changes at a chemical and cellular level. When a movement becomes sensitive, changes occur in the ion channel, neurotransmitters, and nervous system. These changes are driven biopsychosocially.
Following this process, central processes are very much active in all types of pain. For example, acute pain depends on peripherally activated central processes. We must also look at recurrent pain, which is actually a chronic, central process as opposed frequent acute injuries.
Does that mean we need to be psychologists?
We must treat faulty movement patterns, but that does not mean we cannot take aspects from psychology, namely…
Output: Sympathetic, immune, and endocrine systems, potentially consciousness as well.
Step 4: Classify in terms of dysfunction.
General physical function/dysfunction: The patient’s main problems.
Specific physical function/dysfunction: Problems found by clinician that are related to patient’s problems.
Mental/psychological function/dysfunction: What the patient thinks/feels about his/her injury, the clinician, the treatment, and society’s approach to his/her disability. Distress fits in here.
Step 5: Make sense of dysfunction
One needs to determine if the dysfunction is maladaptive or adaptive. For example, limping after a sprained ankle would be an adaptive response to allow for tissue healing. Limping for the same sprained ankle 25 years later would be considered maladaptive. Often too we must realize that we accumulate dysfunction over time, and minor findings may not be relevant to a person’s complaints.
Step 6: Find your sources
In terms of dysfunction and mechanisms. You need to know where you would fire a magic bullet if you have it. This could be a particular manual therapy or even explaining pain to reduce the fear of movement.
Step 7: Know your contributing factors
This can include any factor related to the predisposition, development, and maintenance of a problem. These factors can include psychosocial, genetics, anthropometrics, and ergonomics.
Do no harm is first and foremost. When thinking manual therapy, use the least amount of force for maximum gain.
Step 10: Management
Realize and be comfortable knowing that chronic pain is something we may never cure, but it is something we can manage.
The Reasoning Process: Key Points
Reasoning is an evolving process throughout the treatment course that starts broad and moves toward refinement. This path occurs via the information gained from the patient assessment coupled with the clinician’s knowledge, understanding, and previous experience.
Most important, we must keep the patient as part of the reasoning process. Their hypothesis of their problem affects all reasoning categories and will alter as assessment and management proceed.
The intervention provided will affect the evolving concept of the problem, and the placebo effect can occur anywhere in the process. With that in mind, be mindful of any errors made during.
Neurodynamics is the study and relationship of nervous system mechanics and physiology. The testing protocols for neurodynamics assess the nervous system’s ability to lengthen, glide, and change amongst interfacing structures.
When discussing neurodynamics, it is important to think of the nervous system as a continuum. Mechanical, electrical, and chemical changes in one part of the nervous system affect other related parts.
Gross Movements and Dynamics
When having a nervous system, the following qualities, movements, and buffering capabilities are necessary:
Slide, glide, strain.
Elongate (think gymnasts) and return from elongated position.
Compress (ulnar nerve during elbow flexion).
Stength (kicking a field goal).
Neural Connective Tissue
These include the meninges, nerve root complex, and peripheral nerve structures. Broken down as follows:
Dura mater (outer, tougher)
Pia mater (inner, thinner)
Nerve root complex
Dorsal and ventral roots
Mesoneurium – Sheath that surrounds a nerve. Contracts like an accordion to glide along adjacent tissues. Can become fibrotic with injury.
Meningovertebral ligaments – anchor down to spinal canal, which could become symptomatic.
Rectus capitus posterior is connected to the dura mater between the occiput and atlas; helping the dura fold. Makes you wonder what you are truly doing when you release this structure.
The sympathetic trunk’s proximity to the spinal column makes it susceptible to increased loads with upper cross syndrome.
Meninges are one of the components that may be represented by bilateral receptive fields (see chapter II). This could lead to dorsal irritation felt over a wide, bilateral, nondermatomal region. Dural pain is truly nociceptive, and may occur far from the irritated location. The leptomeninges (arachnoid and pia maters) also have mechanoreceptors, which make it responsive to movement.
The peripheral nerve’s connective tissue sheath is also very sensitive, as it is loaded with free nerve endings and pacinian corpuscles. There are also unmyelinated nerve fibers which contain pain neuropeptides. This component may demonstrate the sheath’s role in neurogenic inflammation.
Space and fluid
There really is no space in the nervous system, as everything is filled up with something.
Axoplasm is the nervous system’s juice, as it carries materials such as ion channels and neurotransmitters throughout. Axoplasm flows at 100-400mm per day, but during ischemia or physical constriction it may decrease or even stop. This substance is also thixotropic, meaning that flow is improved the more movement occurs. This is one reason why poor prolonged postures such as sitting for too long can become uncomfortable.
Blood Thirsty Neurons.
The brain and spinal cord make up 2% of body mass, yet consume 20% of available O2 in blood.
Brain and Spinomedullary Angle
The brainstem and cranial nerves move as the body nerves, and even a mild brain injury (think whiplash) can be associated with chronic pain.
The spinal cord is arranged in folds and spirals which straighten as the cord elongates, with most stretching occurring at the cervical spine. This attribute allows for increased cord protection.
Symptoms may arise from either the neural container/mechanical interface or the nerve itself, so both must be checked.
The sequencing of movements also affects the system’s response. This concept is called tissue borrowing, in which the first movement tested becomes the greatest challenged by other movements. For example, if I move the wrist first in a neurodynamic test, then the nerve in that location would uptake the most tension.
It is also important to mention that when loading the system, accumulation is nonuniform. Depending on where movement comes from, the nerve may get pulled in that direction. For example, near the critical zone at T6, cervical flexion may pull cephalid, whereas knee extension may pull the cord cauded. Other reversal areas include C5-6 and L4-5. Symptoms often show up first at these areas.
When the nerve is stressed available blood flow is affected. A simple increase of 20-30mm Hg pressure can affect blood supply, and generally the longer a stimulus is applied also has an effect. This change can be evident in the various neurodynamic tests.
If a nerve is entrapped, forces do not dissipate as far, which leads to greater strain at affected site.
The best resting position for a nerve depends on the injury.
Central sensitization is a phenomenon that occurs in the dorsal horn, which can be best described via 4 different states:
1) Normal: Inputs = outputs; innocuous sensations are perceived as such.
2) Suppressed: Inputs that would hurt do not; think an athlete who injures himself but finishes the game.
3) Increased sensitivity: Pain system has lower activation threshold, leading to pain spreading and pain with light touch and gentle movement. This change occurs because A beta fibers begin taking over C fiber locations in the dorsal horn.
4) Maintained afferent barrage, CNS influences, and morphological changes: Long lasting changes in the dorsal horn from a persistent driver, such as…
A fiber phenotype changes.
Persistent DRG discharge.
Gene transcription change in dorsal horn neurons.
Inflamed dorsal horn or DRG
Maladaptive beliefs, fears, and attitudes.
Dorsal horn sprouting; A Beta fibers take over C fiber space.
Persistent glutamate activity.
The CNS has an endogenous pain control system which activates during injury threat, noxious cutaneous input, or expectations and learning. Such an example of this is when you go to a healthcare practitioner’s office and no longer hurt. Another example of when this system is activated is during aggressive manual therapy. Think about how good your body may feel after sustained pressure or even a needle to a trigger point.
Central Sensitization Patterns
Symptoms not in neat anatomical/dermatomal boundaries.
Original pain spreads.
Multiple areas: Either linked or get one pain, then the other.
Contralateral side may be painful, though not like the other side (mirror pain).
Clinicians end up chasing pain.
Sudden, unexpected stabs.
Patients call the pain “It.” For example, “It has a mind of its own.”
Ongoing pain perception past normal healing times.
Summation via repetitive activities (sitting at a computer).
Distorted stimulus/response relationship. May get pain 10 seconds or days after stimulus is applied.
Unpredictable response to treatment/input, but ends up being predictable (x may only work 2 days).
Every movement hurts, but not big ROM loss (Symptom instability).
“It hurts when I think about it.”
Can be cyclical.
Change in other systems.
Links to traumatic life events.
Miracle cures can work.
Likely in most syndromes (fibromyalgia, complex regional pain syndrome).
2) Do not focus on finding an anatomical pain source which can make matters worse.
3) False positive are frequent on testing when tissues may be healthy (Eg, positive straight leg raise may just be adding slightly noxious input that results in an increased afferent barrage).
4) The physical exam is best considered a sensitivity test.
Increased levels of norepinephrine (physical stress), epinephrine (mental stress), and cortisol (shut down nonessential systems to maintain homeostasis) are upregulated and contribute to, but do not cause, pain. High sympathetic states can lead to problems that include tissue degeneration, mood swings, slow tissue healing, and increased infection susceptibility in people with chronic pain. Tissue change is particularly evident because the sympathetic nervous system innervates and interacts with muscles, joints, skin, connective tissue, inflammatory chemicals, AIGS, and the DRG. The parasympathetic nervous system is also important to mention to our patients in terms of healing effects of sleep and relaxation.