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Thermography & pain management: no pain, real gain.

Why is pain management so vital, and how can thermography (MIT – Medical Infrared Thermography, or ITI – Infrared Thermal Imaging (ITI)) help you or your loved ones in managing pain?

Perhaps you, or someone in your family, are among the 20.4% (50 million) of Americans (according to CDC figures) who live with chronic pain. Perhaps you are one of the 8% of Americans (19.6 million) who live with high-impact chronic pain so extreme that it prevents you from going to work, or even doing basic housework. Maybe you are one of the hundreds of thousands of recreational athletes who have recently sustained recurring soft tissue damage (e.g., a sprained ankle that won’t go away!). Whatever the source of your pain, infrared thermal imaging might offer an excellent tool in your recovery. Read on to find out how!

Firstly, What is ITI?

Infrared thermal imaging (ITI) is an innovative, low-cost screening tool that analyses patterns in heat and blood flow to quickly identify and monitor inflammation, injury and causes of pain. FDA-approved as a successful adjunct screening technology, ITI offers incredible opportunities in the early and pre-emptive identification of musculoskeletal imbalances that can lead to injury, in the pinpointing of pain and inflammation, and in the management of chronic pain conditions.

How Does ITI Help Manage Chronic Pain Conditions?

When blood flow is obstructed and decreased (due to an injury, or disease – or something as minor as sleeping in an odd position one night!), it can cause hypersensitivity of the surrounding tissue. If not immediately rectified, this hypersensitivity can lead to pain (and even eventual tissue death if the blood flow is not restored!). Returning blood flow to normal can eliminate pain altogether, so understanding the causes of hypersensitivity and disrupted blood flow remains key. 

 

Thermography offers an excellent opportunity to identify and track these changes in blood flow and body temperature, providing a snapshot of physiological changes that can explain the source of pain, and tracking the heat adaptations that always occur with disruptions to blood flow. It achieves this by identifying thermal asymmetries in the body and using that data to identify potential areas of pain, disease, or injury. This ITI data can then be used by a clinician to present a visualization of physiological and functional abnormalities to the patient (via the use of a thermal image), which offers a powerful means of engaging the patient.

 

Medical Infrared Thermography (MIT) takes advantage of the high degree of thermal symmetry emitted by all humans, where heat emission is symmetrical in magnitude and pattern, and where an asymmetry can be considered a warning sign for inflammation of musculoskeletal pathologies (including abnormal vascularization, such as in the case of malignant tumor growth). More and more studies are emerging in recent years of the power of MIT as an aid to diagnosis and treatment for a vast range of complex diseases and conditions, including stroke rehabilitation, cancer, dentistry, spinal cord injury, back pain, renal transplantation, diabetic neuropathy, and musculoskeletal injuries.

Thermography: A Brief History

Does thermography demonstrate a successful track record in the early diagnosis and care of pain-related conditions? The answer, happily, is, yes.

 

Since the US Food and Drug Administration (FDA) approved MIT as an adjunctive screening tool for breast cancer in 1982, MIT has been studied by numerous researchers in the context of multiple chronic pain conditions such as CRPS (complex regional pain syndrome), inflammatory arthritis, temporo-mandibular joint disorder and myofascial pain syndrome. 

 

Thermal imaging techniques have been reported to be successful in the context of all four pain classifications; nociceptive pain (a kind of pain that is caused by the nerves in our body responding to tissue damage (e.g., if we sprain our shoulder), inflammatory pain (caused by the inflammatory response of the body that occurs in response to, say, an infection, and which is designed to aid the healing process); dysfunctional pain (a form of maladaptive pain that occurs without stimuli, e.g., fibromyalgia),  and neuropathic pain (caused by damage sustained to neurons, e.g. due to a tumour, or spinal cord injury, or Complex Regional Pain Syndrome (CRPS)).

 

Let’s take a closer look at how ITI / MIT can help with these four debilitating types of pain, by contributing vastly to an improved quality of life for the patient, and by helping clinicians in selecting the best course of treatment.

ITI, Complex Regional Pain Syndrome (CRPS) & Fibromyalgia

CRPS, also known as reflex sympathetic dystrophy syndrome, is a chronic pain condition caused by the sympathetic nervous system’s continual overstimulation of blood vessels, which causes chronic vasoconstriction and significant pain in the patient. It is more commonly observed in women (80%), usually characterized by severe neuropathic pain, and is usually preceded by an injury (in 77% of cases) or a surgical procedure (11% of cases). 

 

CRPS can cause significant short & long-term changes in skin temperature, specifically at the site of the painful, affected area(s), also exhibiting changes in skin color, and hyperthermia in the localized affected area (which can persist if sympathetic nerve fibers are permanently damaged). ITI can help to diagnose the severity of CRPS using these markers, as measured by skin thermography, to understand the physiological biomarkers underlying observed abnormalities in microvasculature adaptability that contribute to pain in the affected areas (such as lack of oxygenation). Ultimately, ITI offers an excellent means in contributing to the identification of pathophysiological changes that can occur following the hyperactivity of the sympathetic nervous system (e.g., after surgery or injury) that precipitated the onset of CRPS.  

 

Similar to fibromyalgia sufferers, CRMS patients often report sensations of burning, aching, and of feeling exhausted.  Around 84%-90% report allodynia (pain when touched or lightly brushed), with 91-96% reporting static mechanoallodynia (pain in the presence of light pressure). In the case of fibromyalgia, however, patients generally do not exhibit the changes in skin color and temperature characteristic of CRPS, which is potentially why thermal imaging has been used more extensively in the treatment of CRPS cases.

 

Nevertheless, ITI also offers benefits in the treatment of fibromyalgia. For example, thermal imaging can aid in the differentiation of CRPS, fibromyalgia, and chronic fatigue syndrome (CFS), conditions that have sometimes been conflated or misdiagnosed, due to the presence of some pathological similarities. Thermal imaging has also been found to identify the presence of more ‘hot spots’ in fibromyalgia patients, as compared to healthy subjects, adding to our understanding of what still remains an under-researched condition.

Back Pain

Back pain remains one of the most common pain-related problems for Americans today, with 65 million Americans having reported back pain at some time in their life! 

 

Caused by a wide range of diseases or injuries (such as muscle, disc, ligaments, nerve, or joint injury), back pain can severely impact quality of life. Happily, ITI (Infrared Thermal Imaging) offers an excellent adjunct screening tool that can aid effective treatment and recovery, quickly and non-invasively providing data, for example, on the neuropathic pain experienced by a patient (as a result of perivascular microcirculatory sympathetic dysfunction) via measurement of superficial and deep temperature changes at the painful, affected site. This type of feedback can prove indispensable in informing treatment strategies. 

 

Imagine, for example, a scenario where a routine MRI scan uncovers a bulging disc. The patient is subsequently scheduled for surgery. In the absence of ITI data, this might seem sensible; however, whilst disc-related problems have been estimated to be the cause of back pain in around 30% of chronic back pain sufferers, around 80% are diagnosed with disc disease, suggesting potential misdiagnoses and a high rate of potentially unnecessary, invasive surgeries. An ITI scan performed alongside the MRI in this scenario may have provided additional data that uncovered the (non-disc-related) root cause of pain, leading to potentially less-invasive and more successful treatment outcomes and perhaps even avoiding the risk of surgery altogether. 

 

Ultimately, ITI offers a window into the analysis of neuropathic pain in a way that more orthodox diagnostic tests, such as MRI’s or EMG’s, may not always be equipped to achieve. For example, where pain is neuropathic (and is associated with thermal, or vasomotor, changes, which can lead to different types of pain such as causalgia, deafferentation and sensitization, hyperpathic regional pain, allodynic pain and neurovascular dysfunction), ITI can offer fascinating additional insights that might completely alter the trajectory of the patients’ care. 

Sports Injury Prevention

Sometimes there is no greater feeling than hitting the basketball court with our kids or pounding the pavement on a long, Sunday morning run. What doesn’t feel so great, though, is sustaining an injury! 

 

Sports and fitness-related injuries are surprisingly common; according to the National Safety Council (NSC), around 468, 000 Americans suffered exercise-related injuries in 2019. A further 417, 000 were injured whilst cycling, whilst basketball accounted for 404, 000 injuries. 292, 000 were attributed to football, while swimming claimed a further 191, 000 victims. 

 

The great news is that ITI can help get you back on track faster, emerging as powerful tool for the diagnosis and management of exercise-related injuries. 

 

Soft tissue injury – the usual type of injury sustained in sport & fitness-related activity (e.g., a sprained ankle) is an acute injury that can lead to complications and long-term damage if left untreated.

So how can thermal imaging be useful in treating it?

Heat, swelling and redness at the site of injury all reflect a wide and complex range of physiological adaptations that can help or hinder recovery. It is exactly these shifts in heat that thermal imaging focuses on. The release of endothelial nitric oxide (NO), prostaglandins and platelet derived growth factor that accompany soft tissue damage can, for example, lead to observably high heat patterns in the affected areas, causing vasodilation, proliferation, angiogenesis (all of which are detectable using an ITI scan). 

 

Heat patterns in soft tissue injuries can also contribute to a better understanding of recovery periods; if an ITI indicates isothermia (an equal temperature in both sides of the body), for example, then recovery from injury (e.g., a sprained wrist) is likely to be relatively short; the more severe a temperature asymmetry as recorded by the ITI, however, the longer the recovery time is likely to be. A shift from hyperthermia to hypothermia in an injured area can indicate vascular constriction due to potential nerve damage, which an ITI can uncover, whilst the use of an ITI scan to monitor the efficacy of ongoing rehabilitation (e.g., deep tissue massage) on a session-by-session basis can ensure that post-injury interventions are working effectively.

Summary

The use of thermography has emerged with strength in the field of sports medicine in recent years. Yet the value of ITI is not limited to athletes; those of us who have been blighted by acute or chronic pain at any times in our lives may also benefit tremendously from engaging with this risk-free, pain-free, cost effective and non-invasive technology.

References

CDC. (2018). Accessed at: Prevalence of Chronic Pain and High-Impact Chronic Pain Among Adults – United States. Morbidity & mortality Weekly Report. 67, 3, pp. 1001-1006. 

 

Hooshmand, H., Hashmi, M., Phillips, E.M. Infrared Thermal Imaging as a Tool in Pain Management – an 11-Year Study. Part I. Neurological Associates Pain Management Center, Vero Beach, Florida, USA. 

 

Pérez-Concha, T., Tijero, B., Acera, M., Fernández, T., Gabilondo, I., Gómez-Esteban, J.C. (2020).  Usefulness of thermography in the diagnosis and classification of complex regional pain syndrome. Neurologia. 

 

Ioannou, S. (2020). Functional Infrared Thermal Imaging: A Contemporary Tool in Soft Tissue Screening. Sci Rep, 10, 9303.

 

Polidori, G., Kinne, M., Mereu, T., Beaumont, F., Kinne, M. (2018). Medical Infrared Thermography in back pain osteopathic management. Complementary Therapies in Medicine. 39, pp. 19-23.

 

Nahm FS. (2013). Infrared Thermography in Pain Medicine. Korean J Pain. 26, 3, pp. 219-222. 

 

Dahlhamer, J., Lucas, J., Zelaya, C., Nahin, R., et. al. (2018). Prevalence of Chronic Pain and High-Impact Chronic Pain Among Adults — United States. Weekly / September 14, 67, 36, pp.1001–1006.

 

Wurtman, R.J. (2010). Fibromyalgia and the complex regional pain syndrome: similarities in pathophysiology and treatment. Metabolism. 59, 1, pp. S37-S40.

Further Reading

CDC American Stroke Statistics: https://www.cdc.gov/stroke/facts.htm