Sensitization (Part 2): Management Strategies

By Anna-Marie Schmidt, MM, DC, and Robert Vining, DC, DHSc

Chronic pain symptoms can be quite different from acute pain symptoms.1 One possible reason is sensitization, a process whereby neurons become more responsive to pain signals and/or translate non-painful stimuli into pain.2 Part 1 of this series described general neuro-adaptive processes leading to sensitization and clinical diagnostic criteria. Here in part 2, management strategies for persons with sensitization are described.

Sensitization, typically occurring in conjunction with chronic conditions, is influenced by many potential factors.3 Because of this complexity, evidence-based management requires a multi-pronged effort. Strategies include three interrelated areas of focus:3–5

  • Education about biological processes causing pain
  • Addressing lifestyle factors
  • A concentration on long-term improvements

Pain Neuroscience Education

Negative pain-related fears and behaviors can develop when people lack understanding about a condition.6 Changing negative beliefs and behaviors can be accomplished through education about the process of sensitization. Several studies have demonstrated that effective educational programs can positively influence important clinical outcomes.7–10

Pain neuroscience education (PNE) broadly describes an educational program designed to help people better understand and interpret pain. Specifically, PNE addresses the concept that pain from a sensitized nervous system can exaggerate sensations and/or be present without tissue damage.5 PNE goals include decreasing the psychological threat caused by painful sensations through increasing knowledge about how pain occurs.8 PNE attempts to help people reconceptualize pain and correct inaccurate beliefs.11 General principles included in PNE include:11,12

  • Pain does not always provide an accurate measure of the physical state of body tissues.
  • Pain can be affected by physical, cognitive and environmental triggers.
  • The relationship between pain and tissue damage weakens and becomes less predictable the longer pain persists.
  • Pain can be interpreted from perceived danger rather than actual tissue damage.

Education in Action

The analogy of an alarm system is commonly used to explain the nervous system’s role in sensitization.13,14 For example:

One of the roles of nerves in the body is to function as an alarm system. When working normally, the system activates when part of the body is damaged. For instance, injuring the skin with a scratch or breaking a bone triggers the body’s alarm system and we feel pain. In this way, the body is like a car. When a rock breaks a car window, something is damaged, and the alarm system is activated (Figure 1). This is normal.

A sensitized nervous system (i.e., the body’s alarm system), requires less stimulus to activate pain. For example, people with sensitization can feel pain with light touch. Returning to the car analogy, we can describe this phenomenon as the alarm being triggered by something as light as a feather (Figure 2). Likewise, an extra sensitive nervous system interprets light touch as pain.

Lifestyle factors

Continuing with the analogy of an alarm system, the key management question is: What else can help desensitize the alarm system? One way is addressing lifestyle factors known to influence sensitization (Table 1).4 In Table 1, lifestyle factors known to negatively influence sensitization are matched with evidence-based interventions.

It is important to remember that people with sensitization can still injure tissues and require treatment for musculoskeletal conditions. However, because of sensitization, some people may not tolerate some manual therapies. Grounding treatment in sound PNE and addressing negative lifestyle factors can help reduce sensitization, eventually allowing added manual therapy use.18

Conclusion

Addressing all potential management strategies for sensitization is beyond the scope of this article. The referenced articles below can provide more detail about how to implement specific management strategies. It is important to keep in mind the process of sensitization involves nervous system adaptation (neuroplasticity).17 Treatment is designed to halt or reduce this adaptation.3,4 Therefore, the focus should be on long-term improvements, placing emphasis on achieving functional gains rather than short-term pain fluctuations.4,18

Anna-Marie Schmidt MM, DC is a Post-Doctoral Research Scholar at the Palmer Center for Chiropractic Research, Palmer College of Chiropractic.
Robert Vining, DC, DHSc is Associate Dean of Clinical Research at the Palmer Center for Chiropractic Research, Palmer College of Chiropractic.

 

Refe  rences

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