Explain Pain Section 4: Altered Central Nervous System Alarms

This is a summary of section 4 of “Explain Pain” by David Butler and Lorimer Moseley. CNS Alarms While much of talk in rehab deals with tissue injury and tissue pain, realize that the brain always makes the final decision as to whether or not you should feel pain. No brain, no pain. This sentiment does not mean that pain is not real. All pain is real. However, pain is a construct that the brain creates in order to ensure your survival. Spinal Cord Alarms When an injury occurs and the DRG receives impulses from peripheral structures or the brain, the spinal cord neurons must adapt to better uptake all these signals. In essence, the DRG becomes better at sending danger messages up to the brain. This change leads to short term increases in sensitivity to excitatory chemicals. Those stimuli that didn’t hurt before now do (allodynia) and those that used to hurt now hurt more (hyperalgesia). In persistent pain, this change continues occurring to the point where neurons that do not carry danger messages start growing into space where danger messages are taking place. Now innocuous stimuli such as grazing the skin begin hurting. The pain may be normal, but the underlying processes become abnormal. When these spinal cord alarm systems become unhealthy, the brain no longer receives an accurate message of what is going on. The alarms become magnified and distorted.  The brain is told there is more damage in the tissues than is actually present. What is good is

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Explain Pain Section 3: The Damaged and Deconditioned Body

This is a summary of section 2 of “Explain Pain” by David Butler and Lorimer Moseley. Tissue Injury 101 When a body is damaged, pain is often the best guide to promote optimal healing. Sometimes it is good for us to rest, other times it is better to move. A similar healing process occurs for all tissue injuries. First, inflammation floods the injured area with immune and rebuilding cells. This reason is why inflammation is a good thing in early injury stages. A scar forms once the inflammatory process is over. The tissue then remodels to attempt to become as good as the original. Blood supply and tissue requirements determine how fast the healing process occurs. For example, ligaments heal much slower than skin because the former has a lower blood supply than the latter. This may also be a reason why aerobic exercise may speed up the healing process. If present, pain usually diminishes as the tissues heal. However, pain may persist if the nervous system still feels under threat. Acid and Inflammation The alarm sensors described here constantly work and often get us to move. Movement keeps our system flushed. When we don’t move or a physical obstruction is present (e.g. sitting), acid and by-products build up in the body tissues. Oftentimes we will start to feel aches and pains when we stay in a prolonged position, which is our body’s way of saying “get up and move.” Much like the alarm system, inflammation is a primitive way for our

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Explain Pain Section 2: The Alarm System

This is a summary of section 2 of “Explain Pain” by David Butler and Lorimer Moseley. Alarm Signals Our body’s alarm system alerts us to danger or potential danger. This alarm system is composed of sensors throughout the body, the eyes, nose, and ears. It is these sensors that are our first line of defense against harm. If one sensor fails the others take over. Most of these sensors are located in the brain and respond to various stimuli. Some to mechanical movement, some to temperature change; the sensors in the brain particularly respond to chemical activity. What is important to know with sensors is that they have a very short life expectancy of a few days. This cycling means our body’s sensitivity is constantly changing. It is with these life cycles that there is hope for those with chronic pain. Moreover, the rate at which sensors are made is normally stable but can change very quickly in regards to a particular stimulus. So if we take for example one with persistent pain, the rate at which pain sensitivity occurs can be changed. Nociception We lack pain receptors in our bodies. Instead, the various tissues have special neurons that respond to different stimuli. These receptors are called nociceptors, which translates into “danger receptors.” Nociception is occurring all the time, but only sometimes will it end in pain. Nociception is neither necessary nor sufficient for pain. The sensors correspond to particular neurons. In order for these neurons to become excited and

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The Sensitive Nervous System Chapter VII: Assessment with a Place for the Nervous System

This is a summary of Chapter VII of “The Sensitive Nervous System” by David Butler. Education 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. Back trouble. Neck discomfort. Twinges. Feelings. 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. 1)      Geography & nature, aggravating/relieving factors, links. 2)      Mechanism of injury. 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

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The Sensitive Nervous System Chapter VI: Clinicians and Their Decisions

This is a summary of Chapter VI of “The Sensitive Nervous System” by David Butler. Intro 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. For manual therapists everywhere, this creates issues and unease. 1)      Decision making moves toward an external body. 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

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The Sensitive Nervous System Chapter II: A Bird’s Eye View of the Nervous System

This is Chapter II summary of “The Sensitive Nervous System.” Intro Here we develop a framework for understanding the nervous system with pain as the centerpiece. The nervous system is very much misunderstood as an input/output system: Myth: Input/output system. Reality: The nervous system is an active activity constructor. It evolves and learns rather than computes. It is    also widely distributed without a master neuron pool for a particular sensation. The nervous system is made up of two components, hardware and wetware. The Hardware Neurons make up the hardware. These components respond and keep a chemical history of many different inputs and outputs. This is true for each individual neuron, which allows each one to be ready to go when called upon. This hardware is one time when the part actual does equal the whole, as one neuron’s activity resembles the entire Central Nervous System’s (CNS) behavior. The nervous system’s size is near-astronomical. There are approximately 100 billion neurons with 1014 synapses. This figure only factors in the functionally known nervous system components. If we throw in 103 nodes/centers (connected by 105 pathways) and the 10:1 glial cell:neuron ratio, and we have an incredibly dense system in place. A pinhead speck of brain tissue has 350 million connections. This hardware is also very redundant, as very few neurons go straight from sensory organ to cortex.  There are several feedback loops in place which allows for constant checking and rechecking. The Wetware Wetware includes the different neurotransmitters and neuromodulators. Examples

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