A Closer Look At Acute And Chronic Pain

October 7, 2019 / Thomas Cohn, MD

Chronic pain is usually different from acute pain. Acute pain is considered to be directly related to stimulation of sensory receptors for noxious stimuli located throughout the body. It is often related to direct damage or trauma to the body. It also is the normal physiologic response to the various types of sensory receptors that is perceived as noxious or painful. Acute pain is relatively short lasting and is a direct response to direct stimulation of sensory receptors with lengths from seconds to usually less than several months. Chronic pain however is long in duration, lasting over three months and becomes independent of direct stimulation of sensory receptors for acute stimuli.

Chronic and Acute Pain

Chronic pain most often is characteristically different from acute pain. It often involves the nervous system changing on a peripheral and central basis such that sensory signals are perceived differently. In the limbs or other areas, sensory receptors become increasingly able to respond to any stimuli and then sending a signal out into the central nervous system. The nervous system essentially becomes primed for responding to sensory inputs and blasts out a powerful danger signal out of proportion to the intensity of the event. A small touch on the arm could feel like being hit by a sledgehammer.

Chronic pain is divided medically into three types;

Nociceptive
Neuropathic
Central sensitization

It can also be a combination of these. As pain becomes more chronic, the central nervous system becomes more involved and pain has more centralized components. The secondary outcomes of chronic pain over time also become prominent with increased healthcare utilization and often decreased quality of life.

There are multiple correlations in a person’s life that are associated with chronic pain. Common attributes include being female, early life trauma, family history of pain and mood disorders, genetics, sleep disturbances and mood disorders. Certain types of pain that more commonly become chronic include headaches, low back pain and fibromyalgia/diffuse myofascial pain, while the psychological factors of anxiety, depression, catastrophizing, and PTSD are linked to developing chronic pain.

Well-managed and aggressively treated chronic pain comprehensively reduces the incident of chronic pain, but as pain continues ongoing aggressive management can impact the intensity of long-term issues. It is important to treat all aspects of a painful condition. Often there are multiple factors stimulating pain and all the physical problems need to be addressed from muscles, nerves, tendons, ligaments, joints, bones and any other system involved as well as the psychological impacts.

Comprehensive management of symptoms is one of the keys to successful outcomes. Using traditional medical strategies including medications and physical therapy in conjunction with techniques like acupuncture, meditation and improving sleep hygiene may all be necessary in managing pain. Aggressive management of acute pain, especially traumatic or post-surgical, helps reduce the incident of the development of chronic symptoms.

Acute pain is a common arena for most regular physicians. Comprehensive initial management of acute painful conditions reduces the development of more chronic problems. If the pain is showing tendencies toward becoming chronic, involvement of a pain specialist can reduce the impact of the long-term symptoms.

New Technologies For Pain Management

August 19, 2019 / Thomas Cohn, MD

Medicine is evolving as electronic technology invades all aspects of medical care, and pain management is no exception. The areas that have changed the most are imaging technology and implantable devices. What is interesting to patients is how imaging can improve care and implantable devices may help when nothing else is working. The improved imaging makes diagnostic and treatment decisions easier and also makes interventions more precise when tied to management by an astute clinician. No matter how good the technology is, without the skill of a good clinician to understand the medical problem, no solution would be helpful.

The new implantable technology available is peripheral nerve stimulation. This is designed for treatment of pain that is related to damage to a peripheral nerve, such as in the arm or leg. Pain can often be traced to an isolated nerve and preventing that nerve from propagating the pain signals helps to control the problem. These pain issues arise sometimes after amputations with phantom pains, and can be seen after trauma when nerves are damaged. These problems can also occur with surgeries like joint replacements, orthopedic interventions, spinal operations and some fractures. When the pain is not resolving and an isolated set of nerves can be found and successfully blocked with local anesthetic, then nerve stimulation may be appropriate. This is a treatment to consider when simpler interventions like medications, physical therapy, and injections have not been successful.

Nerve Stimulation For Pain Management

The idea of peripheral stimulation has been around for a long time. In the distant past, traditional spinal cord stimulators were used for peripheral nerve stimulation. Unfortunately, at some point this began being abused and since those systems were extremely expensive, this process stopped. In the last two years, new systems have been designed specifically for peripheral nerve stimulation that are very technologically advanced and effective.

One example is electrode stimulation. The electrode is a very thin wire coated in silicone that can be delivered to the right place along the specific nerve with a needle guided by ultrasound imaging. The wire contains a special signal receiver that can be used to help stimulate the nerve and drown out pain signals. Most importantly, the signal generator is now a very small rechargeable unit that is placed on the skin over the end of the electrode. In the near future the electrode may connect even further from the generator such that it may be able to be carried in a pocket or other safe place.

The new technology is FDA approved for peripheral nerve pain from any type of nerve injury. The easiest insurance approval is Medicare, but other providers are starting to approve of such treatments when proven simpler treatments have failed. There currently are at least two manufacturers of equipment, the difference appears to be mainly in the generator’s ability to deliver a variety of signals that may effectively block pain signals and not be uncomfortable to the patient. From experience developed in spinal cord stimulation, the electrical signals can be varied such that the nerve pain is blocked but the patient does not feel any other odd sensations. The net effect is that one can perform activities that were once painful without the ongoing sense of pain.

For pain patients, this new technology is nice since the only thing implanted into the body is a thin wire to the appropriate location. Testing prior to implant is first by a local nerve block with a long lasting anesthetic. If that is successful, than a trial implant can be done for a week or longer to determine if a final implant would be indicated. The permanent implant is a brief outpatient procedure and can be easily removed in the future if necessary.

Pain patients who may benefit from peripheral nerve stimulators include those where pain symptoms have a definite peripheral nerve origin and the pain can be extinguished by blocking just one or possibly two nerves that are nearby each other in the body. The first problems that have been treated have been pain related to shoulder injuries that do not resolve with surgery. Other common orthopedic problems include knee and foot pain after trauma or other surgery with nerve damage or nerve pain afterwards. Amputation phantom limb pain and complex regional pain syndrome are other pain problems that may benefit from this technology. An interventional pain specialist who does implants should be able to help determine if the pain problem may be helped with such treatment. Not all pain problems can be helped and if the pain is coming from multiple pain generators or is centrally generated in the brain, this treatment is less likely to be helpful.

Could This Be The Next Big Thing In Pain Management?

June 10, 2019June 10, 2019 / Thomas Cohn, MD

Last Sunday in the science section of the newspaper there was an article about research on a new pain drug. The scientists behind the drug are convinced they have the next great drug. The skeptic in me hopes but doubts it. The reason the news has not made the traditional rounds in in all the reputable medical sites that spread news of discoveries. Furthermore, the work to date is only in animals and there has not been definite evidence this will transfer to humans.

The article discusses the work of Dr. Bruce Hammock, an entomologist at University of California-Davis. In the 1970’s he was working on an enzyme that converted a corn ear-worm to an insect. Removing the enzyme essentially killed the insect before it converted to the moth and was able to breed. Overall this was not found to be a cost effective strategy for this insect to be controlled. Since that part of his work did not pan out, he started looking for how the enzyme or related enzymes might occur in other species. especially humans.

Eventually Dr. Hammock found these compounds in humans and they supposedly reduce pain. Of note, he does not specify what these compounds are, but only says they are chemically broken down rapidly in the body naturally. He then found a way to keep them from being broken down in the body as quickly. Dr. Hammock believes this compound can somehow help relieve pain.

Believe It When We See It

The reason to be skeptic is that naturally this compound that reduces the intensity of pain is very transient in the body by the description given. This makes me believe it is likely easily broken down by chemicals in the body and is in a very limited location. This type of compound is very hard to deliver conveniently (like a pill) into the body and be absorbed. It is also likely to be easily broken down no matter what one does. Lastly, the chemical sounds like it may be something that exists in the nervous system, and thus isolated by something like the blood-brain barrier.

The researchers behind this new novel compound are just looking at starting human trials. So far there has been little funding toward the research from what has been said in the regular press. Further, as noted earlier there is no information in the extensive research pain literature on the animal-level studies discussing this compound. If the research was really promising, more money would be involved without question since pain treatment is a billion dollar industry with huge potentials.

The bottom line is that there is research going on in the field of pain medicine trying to develop new treatments and medications. However, whether any of the current research will lead to new drugs is difficult to guess. A lot of treatments have been proposed but most die as they are tested. Human studies usually take between five and 10 years to complete. Only time will tell if this research will ever lead to a new drug that is useful to treat pain.

Get Your Vitamins and Minerals From Food, Not Supplements

April 23, 2019 / Thomas Cohn, MD

Many people ask about taking dietary supplements, vitamins, minerals, and various natural compounds to improve their pain and their life. These are not officially regulated as far as how well they work. They are regulated only to the level that they cannot be toxic when ingested and they have become a billion dollar business.

Are They Effective?

Recently, a large study was done with regards to multiple dietary supplements, with an extra emphasis on medications with claims of helping with heart disease and natural degeneration caused by aging. Simply put, nothing had any positive impact on health for any of the compounds being pushed. The study was published in JAMA in January 2019 and looked at many different compounds. Included were ginkgo balboa, coenzyme Q10, coral calcium, and many others. These are all found in the vitamin and supplement aisle of many stores. None of these promoted items had any impact on cardiac health, dementia, cognition or any general component of health. Basically, none of these vitamins, compounds or minerals made a difference.

The answer of what really works is eating healthy. All these various compound are found in our fresh foods. Eating fresh food provides nutrients in a way through the gut that the appropriate vitamins and minerals are absorbed correctly and can be used by the body. In pill form or other concentrate, the body often will not be able to utilize the compound successfully. Many times the form of the compound in a pill is not absorbed or is destroyed by the body’s digestive processes. When we eat our food, our digestive system can find the nutrients and make sure they travel to the correct areas of the body. All the studies show that nutrients that come from eating a good diet are helpful, and adding a variety of supplements shows no benefit.

The best suggestion based on all these medical studies is save the money spent on supplements and spend the money on eating a healthy diet with fresh fruit and vegetables and low fat protein. Highly processed foods with high carbohydrate loads often do not have a high nutritional value. Develop a diet that comes from the outer aisles of the grocery where the fresh foods are found. None of the claims for supplements have really be proven, so save your money for now.

Could Wearables Replace Opioids For Pain Management?

October 5, 2018 / Thomas Cohn, MD

Chronic pain affects roughly 100 million Americans, and the pain management market is estimated to be about $635 billion a year. With so many people to treat and money to be made by finding new, safer treatment options, a number of different technology companies are jumping into the world of pain management.

One area that is of particular interest to these companies is wearables and how they can be used to combat and treat chronic pain. A recent study involving more than 1,600 people with distal and proximal chronic pain focused on the Quell wearable device. The wearable allowed patients to track their pain in real time, including changes in pain intensity and pain interference with sleep, activity and mood on an 11-point scale. Patients tracked these changes over the course of two months, and researchers analyzed the findings at the conclusion of the study.

But tracking wasn’t the only feature available with the wearable. The unit actually provided high-frequency transcutaneous electric nerve stimulation. Many patients found that when they wore the device and it was emitting signals, that their pain levels decreased.

“[We found] statistically and clinically significant decreases in pain interference with activity and mood” and “a clinically significant decrease in pain intensity and less pain interference with sleep,” researchers wrote.

Wearables and the Future of Chronic Pain Management

The quell device was only helpful for a select number of people dealing with certain types of chronic pain, but the technology behind the device is exciting. It’s like a hybrid Fitbit and TENS unit, and as the technology continues to progress, we may soon see wearables that can work to drown out pain signals in all different areas of the body.

We understand the science, but because pain is such an individualized issue, there’s no one-size-fits-all wearable for chronic pain. Opioids do a better job of controlling a wider type of pain, but they come with their own potential drawbacks, including potential addiction and dependence. Wearables do not present the problem of dependence, but the tricky part is getting them to impact the specific nerve pathway that is causing pain.

We need to keep investing money in these alternative treatment options and in pain management as a whole. It seems like we’re nearing a breakthrough, not just with wearables, but as a whole. Pain is a huge industry affecting tens of millions of people, so it’s going to draw attention and investments. The first company to develop a wearable or another opioid alternative that can reliably control certain types of widespread pain will set the bar and enjoy the spoils that come with it. This will lead to more investments, better technology, and hopefully, better non-opioid patient care options for chronic pain. We’re excited to see what the future holds.