Understanding Chronic Pain

Whether minor or severe, chronic pain affects 29 percent of Australians and about 15 to 20 percent of Americans each year. In Australia, the total cost of chronic pain is estimated to be around $34.3 billion including lost productivity, attribution to other illnesses such as depression, heart disease, and cost of the health system.

According to the International Association for the Study of Pain, pain is defined as an unpleasant sensory and emotional experience associated with actual or potential tissue damage (Merskey & Bogduk, 1994). The Australian definition for chronic pain is defined as pain that extends beyond the expected healing time of an injury or can accompany chronic illnesses such as arthritis or lupus” (Pfizer Health Report, 2011; Stollznow Research for Pfizer Australia, 2010).

All pain experiences are normal experiences to what your brain thinks is a threat. The amount of pain you experience is not commensurate with the amount of tissue damage. Acute pain is thought to be an important and adaptive signal. It tells us a message or warning that something is damage in our body. Sometimes pain can misinform us. It reminds us that we are in danger and we needs to avoid that.

Pain receptors are called nociceptors, and are scattered all over our body. It transduces noxious stimuli into nociceptive impulses. Electrical impulses are being transmitted to the spinal cord via afferent nerves and then along sensory tracts to the brain. The neural signal will modulate the pain by amplifying it. Consequently, we will experience the pain through this process. During this process psychological and social factors are involved, and as a result it may aggregate the pain.

When we receive our pain signals, some chemicals are produced to calm down the system to inhibit the pain reaction while the other chemicals excite the system to stimulate the pain response. The pain experience is related to ascending, and descending messages and this process happens in the spinal cord itself (Wales, 2012a). If there are more inhibitory chemicals, the person may feel more pain, and if there are less of the inhibitory chemicals, the pain may be less. Messages ascend to the brain through the spinal cord to inform a threat in tissue damage and is called neuropathic pain.

Pain centralized in the nervous system can become very sensitive, and after a while, it adapts to it. In the end, even low-key events are perceived as painful. Fibers with messages descending from the brain involve the sympathetic and parasympathetic nervous systems. Those nerve fibers that associate with the sympathetic and parasympathetic systems make a contribution to the pain experience. The role of the sympathetic system is to protect us during dangerous time by the stress hormone adrenalin and the good hormone endorphin into our body. If it lasts too long, the chemical cortisol will damage our body and brain and will make us feel sick. Chronic pain can lead to depression, mood changes, anger, anxiety insomnia, and it will make the patients feel stressed all the time.

In the early 1960s by Ronald Melzack and Patrick Wall, they proposed a Gate Control Theory. They suggested that pain signals encounter what are called nerve gates in the spinal cord that open or close dependent on a number of factors and may be involved instructions coming down from the brain. When the gates are open, pain messages can get through, and pain can be intense. When the gates are close, pain messages are being prevented from reaching the brain and may not even be experienced at all. It is believed that something must be happening to modulate the experience of pain.

Depressed mood and stress can affect the intensity of the pain the person feels. Dr Irene Tracey at Oxford University demonstrated that subjects even thinking of the pain can add an increase activation in their pain-circuits. She also found out that distraction can also cause some reduction in tension as it obviously disrupts the continuation of the cognitive thinking process that has been focusing on the pain sensation.

On the other hand, people experiencing trauma may have their pain experience shut down at that point in trauma, and the body may also release the beta-endorphins, our internal pain killers, to shut down the pain. However, it is only for short-term. Chronic stress on the other hand does not produce analgesia. Instead, it produces hyperalgesia or increased sensitivity to pain. It is believed that it is triggered by high levels of glucocorticoids that involve some structural rewiring of the central nervous system.

Treatment of chronic pain can be managed by pharmacotherapy such as the opioid drug family. It resembles our own bodies’ pain relievers, the endogenous opiates. Sometimes physiotherapy may require helping patients strength their muscles or ligaments to prevent them from further injury in the future.

There are some treatments and techniques that could help manage the pain. If you are suffering from chronic pain, most of the time you are causing pain with your thoughts and emotions. If this is the case, you could benefit from have a psychologically validating intervention. This could help you work out with some accuracy how your thoughts, feelings, and movements all impact on the nervous system affect your chronic pain. Cognitive behavior therapy treatment is quite effective in helping patients with chronic pain challenge their maladaptive cognitions including catastrophising, all-or-none thinking, and maximizing/minimizing, etc. Somatic quieting is preferable for patients to relax rather than tensing their body muscles thus reducing stress and alleviating pain. Graded or gradual physical activity is involved in the CBT to help patients slowly build up their muscles strengths.

Magnet therapy is believed to relieve Headaches, arthritis, menstrual cramps, carpal tunnel syndrome, and sports injuries (Whitaker & Adderly, 1998). Hypnotherapy is a viable alternative to psychopharmacological interventions for controlling acute, chronic, and postoperative pain, as well as pain from nonsurgical procedures (Patterson, 2010).

References:

Butler, D., & Moseley, L. (Second Ed) (2014). Explain pain. Neuro Orthopaedic Institute. Noigroup Publications.
GoodTherapy.org (2013). Chronic pain. GoodTherapy.org. Retrieved on 2 April, 2017, from: http://www.goodtherapy.org/learn-about-therapy/issues/chronic-pain.

Medtronic (2013). Improving life by easing chronic pain. Medtronic, Inc. Retrieved on 2 April, 2017 from: http://www.medtronicneuro.com.au/chronic_pain_causes.html.

Patterson, D.R. (2010). Clinical hypnosis for pain control. Washington: American Psychological Association.

Pfizer Health Report (2011). Australians living with chronic pain. Pfizer Health Report, 46, p 4.

Satterfield, J.M. (2015). Lecture 19 Mastering chronic pain. In Jason.M.Satterfield. Cognitive behavioural therapy: Techniques for retraining your brain. The Great Courses. Chantilly, VA.

Stollznow Research for Pfizer Australia (2010). Chronic pain. Stollznow Research for Pfizer Australia. Australia: Pfizer Australia Pty Ltd.

Wales, C. (2012a). The nervous system. Chronic Pain Australia. Retrieved on 22 May, 2013, from: http://www.chronicpainaustralia.org.au/index.php?option=com_content&view=article&id=31&Itemid=233.

Whitaker, J., & Adderly, B. (1998). The pain relief break through: The power of magnets. Boston: Little, brown and Company.

Gabriel Wong
Clinical Psychologist