From The Lab
By Ted Swing, Ph.D

The experience of pain is one of the most important medical challenges of our time. Pain is the most common reason people seek medical care in the U.S. Chronic pain, defined as pain lasting several months or more, affects one third of American adults, with 9% experiencing moderate or severe chronic pain.

One of the first steps in treating painful conditions is assessing that pain, which generally includes the patient providing a numerical rating, often from zero (no pain) to ten (the worst pain imaginable). However, the effects of chronic pain go beyond the immediate suffering captured by such a number and can affect people’s lives in a number of ways.

Multiple Effects of Chronic Pain

Chronic pain can reduce a person’s quality of life. For example, chronic pain sufferers lose an average of 1.5 hours of sleep per night due to their pain. Chronic pain can also have consequences for mental well being. Those in moderate to severe chronic pain suffer from anxiety and depression at roughly twice the rate of those who don’t. The number of activities a person can do, such as spending time with family or friends or taking part in hobbies, is often affected by chronic pain. It also interferes with many adults’ ability to do paid work. Specifically, it is estimated that chronic pain causes losses of income of $280 billion each year in the U.S. due to the inability to work or reduced hours. All of these effects not only help to illustrate why chronic pain is so important to treat, but also show that the consequences of chronic pain show up in many facets of a person’s life.

Comprehensive Assessment of Pain

Because chronic pain affects people in such varied ways, it is important to assess it with more than just direct questions, such as average pain and current pain numbers. For example, suppose a patient came to their doctor with an average pain of 6 out of 10. They were unable to do most of the activities they used to enjoy and were depressed about that fact. After various treatments, their pain decreased to a 3 or 4 out of 10, and they finally felt good enough to start doing some of their old activities again. The patient may be quite happy about that, but at the same time the increased activity brings their pain back up to a 4 or 5 by the next time they visit their doctor. If one looked purely at the pain numbers, this might not seem like a significant improvement. Yet, to the patient, this may be quite substantial because they’re doing the things they enjoy again and this has improved their mood.

To capture changes such as this in a way that better informs the doctor when treatments are or aren’t effective it is important to assess outcomes such as loss of sleep, mood and daily activities. For this purpose, we’ve developed and validated a 20 item questionnaire called the Global Pain Scale. We will be expanding our use of this scale to better capture changes in patient well being to assist us in delivering the most effective treatments.

Ted Swing has more than ten years of research experience and four years of teaching experience in psychology, has published in top psychology and medical journals, and has presented his research at major conferences. He received his Ph.D. in Social Psychology from Iowa State University and has been the Research Director at Arizona Pain since May 2012.

From the Lab
By Ted Swing, Ph.D.

One of the rapidly advancing areas in the treatment of chronic pain is the use of implantable neurostimulation devices. The most common of these are spinal cord stimulators. These devices are typically used in patients who have failed to get adequate relief from medications and conservative treatments such as physical therapy and chiropractic care. Patients who have had surgical procedures in the spine without obtaining relief may also be appropriate candidates for these treatments.

What is a spinal cord stimulator?

Spinal cord stimulators (SCS) are devices that typically consist of one or more leads with multiple electrodes. These leads are placed in the spine along the cord of nerves that transmits pain signals to the brain. These leads connect to a battery that generates electrical pulses in the leads. These electrical pulses are calibrated to disrupt pain signals coming from a particular body region, such as the lower back and legs. Patients with a spinal cord stimulator will feel a mild tingling sensation in place of the pain they normally feel.

Spinal cord stimulator trial systems

Before permanently implanting a spinal cord stimulator, patients will spend several days with a trial system. This system functions much like the permanent spinal cord stimulator system, but only the leads are implanted. The leads run through the patient’s incision site to an external stimulating system. Trying this system allows the patient to find out if the spinal cord stimulator will provide them with pain relief using a temporary system that can be easily removed at the end of the trial. This trial typically lasts about five days and then the trial system is removed. If the patient receives good pain relief, they can have a permanent spinal cord stimulator system implanted.

St. Jude Medical Invisible Trial System

St. Jude Medical is a leader in developing spinal cord stimulator systems. They recently developed the Invisible trial system. Unlike the current trial systems which have a cable connecting the lead to the external stimulator, this system has the lead connected to a Bluetooth device at the incision site. This Bluetooth device wirelessly connects to a controller that the patient can use to turn the stimulation on and off and make other adjustments. This new trial system is being studied and is not yet commercially available.

Invisible Trial System Study

We will be working with St. Jude Medical this spring to test this new system to see if patients find it more convenient than the current trial systems. Eligible patients who are getting a spinal cord stimulator trial can enroll in this study. They would complete the normal trial, except that they would use the current trial system for the first few days before switching to the Invisible trial system for the final few days of the study. They would provide feedback about each system.

If you are interested in getting a spinal cord stimulator, you can speak with your pain management providers. For additional information about this study you can contact me directly at TedS@arizonapain.com.

Ted Swing has more than ten years of research experience and four years of teaching experience in psychology, has published in top psychology and medical journals, and has presented his research at major conferences. He received his Ph.D. in Social Psychology from Iowa State University and has been the Research Director at Arizona Pain since May 2012.

What’s going on in the Research department.

By Ted Swing, Ph.D.

The development of new treatments for pain depends on studies called clinical trials. Clinical trials are studies that typically take place at many locations around the country — sometimes around the world. The study is supported by a sponsor, but the treatments are overseen by doctors at each individual location. Clinical trials may study the effectiveness and safety of a new drug, a surgical procedure, or a medical device. At Arizona Pain, we are committed to advancing the treatment of pain, so we are taking part in several clinical trials.

Active Clinical Trials

St. Jude SENSE Study

Patients who have moderate to severe chronic pain that is not resolved by conservative treatments, such as rest, physical therapy, chiropractic care or medication therapy, may qualify for treatment with a device called a spinal cord stimulator. This is an implanted device that delivers electrical pulses to the nerves of the spine that disrupt pain signals, producing pain relief.St. Jude is conducting a study comparing the standard spinal cord stimulator to new type of device that stimulates both the spinal nerves as well as peripheral nerves in the lower back. The study is intended to test if patients who have had back surgery and continue to experience pain in the lower back and legs may get better relief from the combination system than the standard spinal cord stimulator.

Seikagaku Herniated Disc Study

The discs separating the spinal vertebrae can bulge outward, putting pressure on the nerve roots. When this happens in the lower back, it can cause pain and numbness that shoots down one or both legs.Seikagaku is studying a drug that is injected into the bulging disc that may be able to permanently shrink the bulging disc, relieving the pressure on the nerve root and the pain it causes. Patients who have suffered from back and leg pain due to a bulging disc for no more than one year and who have never had surgery in their lumbar spine may be eligible to participate. Of patients enrolled in this study, 75% receive an injection of this study drug and 25% receive a control treatment.

Pfizer Lyrica Post-Traumatic

Peripheral Nerve Pain Study

Traumatic injuries, such as car accidents, falls or even surgical procedures, sometimes leave patients with chronic nerve pain in the area of the injury. This can affect peripheral nerves, which are nerves outside of the head, neck or spine. Because this pain is due to damage or irritation of the nerve itself, it may last after the injury itself has healed. For example, a person may have injured their shoulder in a car accident and suffer chronic nerve pain that runs from their shoulder and into their arm.Lyrica is medication currently approved for several types of nerve pain. Pfizer is currently studying Lyrica for the potential to treat post-traumatic peripheral nerve pain as well. Patients who suffer from post-traumatic peripheral nerve pain may be eligible to enroll in the study and receive either Lyrica or a placebo medication for up to 17 weeks.

Pfizer Arthritis Cardiovascular

Disease Study

Osteoarthritis and rheumatoid arthritis are among the most common causes of chronic pain. Many patients with these conditions require treatment with anti-inflammatory medications, such as ibuprofen (e.g., Advil®), naproxen (e.g., Aleve®) or Celebrex®. There is some concern, however that these medications can increase the risk of cardiovascular problems in patients who are at risk.

Pfizer is conducting a large scale study at hundreds of sites around the world to determine which of these medications is safest for patients who are at risk of cardiovascular disease. Risk of heart disease is based on (a) coronary artery disease, (b) peripheral vascular disease, (c) diabete [if female, then diabetes requiring insulin] or (d) a combination of age, smoking, high blood pressure, family history of premature cardiovascular disease, and other risk factors. Patients who have osteoarthritis or rheumatoid arthritis that requires treatment with anti-inflammatory medication and meet one or more of the cardiovascular risk criteria may be eligible for this study. Patients enrolling in the study will be randomly assigned to receive one of three widely used arthritis medications (ibuprofen, naproxen, or Celebrex®) over the course of the study.

If you are interested in learning more about any of these studies, you can speak with your pain management providers or contact me directly at TedS@arizonapain.com. Ted Swing has more than nine years of research experience and four years of teaching experience in psychology, has published in top psychology and medical journals, and has presented his research at major conferences. He received his Ph.D. in Social Psychology from Iowa State University and has been the Research Director at Arizona Pain since May 2012.

From the Research Dept.
New Study to Examine the Efficacy of Burst Neurostimulation
By Ted Swing, Ph.D.

One of the frontiers in the treatment of chronic pain is neurostimulation (also called neuromodulation). Neurostimulation involves devices that deliver electrical pulses to alter nerve responses. When used in the brain, this can be used to prevent epileptic seizures or treat Parkinsonâ€s disease. The most common applications of neurostimulation involve the treatment of central or peripheral nerves in order to produce pain relief. The electrical pulses sent by a neurostimulator trigger sensations in nearby nerves that are often felt as a mild tingling or buzzing sensation. This sensation replaces some or all of the pain that would have otherwise been perceived in that nerve.

Spinal Cord Stimulators

The first type of neuromodulation device, developed in 1968, is called a spinal cord stimulator (SCS). Spinal cord stimulators are devices implanted under the skin along the spine. The device consists of a battery and pulse generator, along with electrodes running along the spinal nerves. These electrodes are positioned to stimulate the specific nerves for the area or areas where that patient has pain. These devices have proven effective for many patients and are widely used today for chronic pain that is not adequately relieved by other treatments.

Potentially Unpleasant Stimulation

One of the challenges with spinal cord stimulators is that the intensity of the stimulation felt by the patient can vary, for example by time of day, type of activity or by body position. A particular level of stimulation may provide effective relief when the patient is standing, but then become too intense when they sit down. This intense stimulation could be unpleasant. Alternatively, if the neurostimulator were set to a level that is effective in one body position, it may become insufficient to cover their pain in a new position. Though the stimulation delivered by the device can be adjusted by the patient to prevent periods of unpleasant or insufficient stimulation, it would be preferable if relief could be produced consistently without potential discomfort. Further, for a small percentage of patients, the feeling of neurostimulation in general is considered unpleasant.

Burst Stimulation

One possible solution to these challenges is the use of burst stimulation. Rather than delivering constant pulses of electrical stimulation, burst stimulation would involve very brief pulses of stimulation (for example, a series of five electrical pulses in a row, each lasting 1/1000 of a second). These bursts would be repeated many times each second. Previous research shows that such pulses are too short to felt by the patient, but are capable of producing pain relief. One of the leaders in neurostimulation devices, St. Jude Medical, has begun a study comparing burst stimulation to standard stimulation. This study will determine if the pain relief produced by burst stimulation is as good as or better than standard stimulation.

St. Jude SUNBURST Study

The St. Jude SUNBURST study will include patients with moderate to severe pain in the trunk or limbs that is not adequately relieved by medications or other treatments. These patients must be appropriate candidates for implantation of a neurostimulation device and meet other criteria, including not being pregnant, having cancer, or being immunocompromised. Patients who qualify will have a trial spinal cord stimulator implanted for several days. This will show whether or not neurostimulation is effective in relieving the patientâ€s pain. If it is, then a permanent spinal cord stimulator will be implanted. Patients are then randomly assigned to receive either standard stimulation throughout the study or periods of standard and burst stimulation. The study will then involve at least four follow up visits over the next 24 weeks and then an additional visit every six months until the study is completed. Arizona Pain will be taking part in this study. If you are interested in learning more about this study, you can speak with your pain management providers or contact me directly at TedS@arizonapain.com.

Ted Swing has more than nine years of research experience and four years of teaching experience in psychology, has published in top psychology and medical journals, and has presented his research at major conferences. He received his Ph.D. in Social Psychology from Iowa State University and has been the Research Director at Arizona Pain since May 2012.